HJM Barnett, for the North American Symptomatic Carotid Endarterectomy Trial Collaborators (John P Robarts Research Inst, London, Ont; et al )
Benefit of carotid endarterectomy in patients with symptomatic moderate or severe stenosis.
N Engl. J Med 339:1415-1425, 1998.
Carotid endarterectomy (CEA) in patients with symptomatic stenosis of 50% to 69%, reduces stroke risk by a modest but significant degree. However, CEA in patients with less than 50% symptomatic stenosis is of little value.
AR Naylor, A Bolia, RJ Abbot et al (Leicester Royal Infirmary, England) :
Randomized study of carotid angioplasty and stenting versus carotid endarterectomy: A stopped trial. J Vasc Surg 28: 326-334, 1998.
J May, GH White, W Yu, et al (Univ of Sydney, Australia) :
Concurrent comparison of endoluminal versus open repair in the treatment of abdominal aortic aneurysms: Analysis of 303 patients by life table method. J Vasc Surg 27: 213-221, 1998.
The long-term outcome after endoluminal repair (ER) of abdominal aortic aneurysm (AAA) is not known, and concurrent comparison studies of ER and open repair (OR) have not been conducted. Results of a concurrent comparison of ER and OR in consecutive patients with AAA using life table analysis are presented.
Isner JM, Baumgartner I, Rauh G, et al [ Tufts Univ, Boston]
Treatment of Thromboangiitis Obliterans [Buerger’s Disease] by Intramuscular Gene Transfer of Vascular Endothelial Growth Factor : Preliminary Clinical Results
J Vasc Surg 28: 964-975, 1998
Buerger’s disease, also called thromboangiitis obliterans [TAO], is a
peripheral artery occlusive disease affecting young smokers. Once critical limb ischemia with ulceration or gangrene has occurred, the course of TAO is relentlessly progressive, even if the patient quits smoking.
The patients received 2 treatments with naked plasmid DNA-encoding vascular endothelial growth factor [ph VEGF165]. The treatments, given 4 weeks apart, consisted of direct IM injection at 4 arbitrary sites in the ischemic extremity.
To be successful, gene therapy must be initiated before the onset of forefoot gangrene.
VEGF has shown considerable early promises in the treatment of coronary and peripheral vascular disease.
JS Matsumura, for the EVT investigators (North Western Univ, Chicago, et al) :
Continued expansion of aortic necks after endovascular repair of abdominal aortic aneurysms.
J Vasc Surg 28:422-431, 1998.
Aortic neck dilatation sometimes occurs after repair of an infra-renal abdominal aortic aneurysm (AAA). Continued dilatation could lead to endoleak or catastrophic device failure after endoluminal aneurysm repair.
Aortic neck expansion after AAA repair continues for at least two years, raising the likelihood of later failure after endoluminal AAA repair.
Review of Vascular Surgery
Recent Advances in Surgery-23, Year-2000
The Conventional open treatment of abdominal aortic aneurysm [AAA] is now well established and is an effective way of preventing death. The feasibility of repair of AAA using endovascular techniques continues to be evaluated although when, and if, this approach might replace open repair, remains uncertain.
Surgery cannot be recommended to patients with an asymptomatic small AAA.
Patients with an AAA of 6 cm or less can be managed conservatively.
The prevention of AAA rupture, that has an overall mortality of up to 90%, can only be achieved by early detection, since most AAA are asymptomatic up until the time of rupture. Early detection can be achieved by ultrasonographic screening.
Carotid Artery Angioplasty –
The role of surgery in the treatment of symptomatic carotid artery stenosis is now well established.
The concern over periprocedure stroke and cerebral ischaemia secondary to embolisation and thrombosis remains, and has restricted the wide-spread adoption of carotid angioplasty.
Venous Ulceration and Seps-
Leg ulcers present a significant problem to patients.
Ulceration is the end result of venous reflux causing chronic venous hypertension. Reflux may originate from superficial veins [about 50%], deep veins [30%] or both.
Subfascial endoscopic perforator surgery [SEPS] is an attractive approach employing the techniques of minimal access surgery.
N.R. Tai, H.J. Salacinski, A. Edwards*,G. Hamilton and A.M. Seifalian [ Vascular Haemodynamic Laboratory, University Department of Surgery, Royal Free and University College Medical School, University College London and Royal Free Hospital, London and Cardio Tech International Ltd., Wrexham, UK]
Compliance Properties of Conduits used in Vascular Reconstruction
Br. Jour. of Sur. Volume 87, No.11, November 2000, Pgs- 1516-1524
This study quantifies the elastic properties of a new compliant poly [carbonate] polyurethane [CPU] vascular graft, and compares it with grafts made from CPU, expanded polytetrafluoroethylene [ePTFE], Dacron and human saphenous vein with that of human muscular artery.
A pulsatile flow phantom was used to perfuse the conduit at physiological pulse pressure and flow. The intraluminal pressure was measured by a Millar Mikro-tip catheter transducer and the vessel wall motion was determined with duplex ultrasonography. Diametrical compliance and stiffness index were then calculated for each conduit over mean pressures ranging from 30 to 100 mmHg by 10-mmHg increments.
The compliance values of CPU and artery were similar although the elastic behaviour of the artery was anisotropic unlike CPU, which was isotropic. Dacron and ePTFE grafts had lower compliance values. In both these cases compliance and stiffness differed significantly from that of the artery. Human saphenous vein exhibited anisotropic behaviour and, although compliant at low pressures, was markedly incompliant at higher pressures.
B. Wolf, D.M. Nichols* and J. L. Duncan[ Departments of General Surgery and * Radiology, Raigmore Hospital, Inverness, UK]
Safety of a Single Duplex Scan to Exclude Deep Venous Thrombosis
Br. Jour. of Sur. Volume 87, No.11, November 2000, Pgs- 1525-1528
Guidelines advocate that a negative ultrasonographic scan needs to be followed by venography, or a repeat scan to detect potentially missed calf vein thrombosis.
This study evaluates whether anticoagulation can safely be withheld on the basis of a single negative duplex scan.
537 patients had 709 leg scans performed for suspected DVT. Among 352 patients, who had 429 negative leg scans, four possible adverse events were identified. [1.1% per patient and 0.9% per leg] suggesting it is safe to withhold anticoagulation after a single negative scan.
D.R. Chadwick, B.J. Harrison, P. Chan*, L. Chong and P. Peachell [ Departments of Endocrine Surgery and *Vascular Surgery, Northern General Hospital and Section of Molecular Pharmacology and Pharmacogenetics, University of Sheffield Royal Hallamshire Hospital, Sheffield, UK]
Vasoactive and Proliferative Effects of Parathyroid Hormone and Parathyroid Hormone-Related Peptide on Human Vascular Smooth Muscle
Br. Jour. of Sur. Volume 87, No.11, November 2000, Pgs- 1529-1533
Hyperparathyroidism is associated with an increased incidence of hypertension and cardiovascular disease. This probably results from desensitization of the normally inhibitory effects of parathyroid hormone-related peptide [PTHrP] on vascular smooth muscle cells [VSMCs] by previous exposure to parathyroid hormone [PTH].
This data implies that homologous desensitization to PTHrP is not implicated in the pathogenesis of vascular disease in patients with hyperparathyroidism.
A.J.P. Sandison, C.H. Wood, T.S. Padayachee, A.C.F. Colchester and P.R. Taylor [Departments of Surgery, Anaesthesia, Ultrasonic Angiology and Neurology, Guy’s and St Thomas Hospital Trust, Guy’s Hospital London, UK]
Cost-effective Carotid Endarterectomy
BRJ Volume 87, No.3, March 2000, Pg.Nos. 323-327
Although carotid endarterectomy is increasing in the UK, there is evidence that the procedure is still underused.
The number of preoperative investigations was reduced; angiography and cerebral computed tomography were reserved for specific indications.
The median duration of hospital stay decreased from 7 to 2 days.
There was no change in the stroke and death rate [3 per cent] during the study.
Carotid endarterectomy can be performed cost-effectively using non-invasive preoperative investigations for the majority of patients. In-hospital stay has been reduced and the routine use of intensive care replaced by a 2-h stay in theatre recovery. These changes have been achieved without compromising patient safety.
Franklin IJ, Harley SL, Greenhalgh RM, et al (Charing Cross Hosp, London)
Uptake of Tetracycline by Aortic Aneurysm Wall and Its Effect on Inflammation and Proteolysis
Br J Surg 86:771-775, 1999
Proteolytic degradation of the aortic wall by matrix metalloproteinases (MMPs) is thought to play an important role in the pathogenesis of abdominal aortic aneurysms (AAAs). Tetracycline derivatives inhibit many of these MMPs.
Tetracycline rapidly penetrates the aortic wall. However, the concentration achieved may not be sufficient to change collagen turn over through limitation of MMP production or activity.
The potential of tetracycline to retard or inhibit the expansion of aneurysms has been known for years.
Teirstein PS, Massullo V, Jani S, et al (Scripps Clinic, La Jolla, Calif; Brigham and Women’s Hosp, Boston; Washington Hosp Ctr, Washington, DC)
Three-Year Clinical and Angiographic Follow-up After Intracoronary Radiation: Results of a Randomized Clinical Trial
Circulation 101:360-365, 2000
The results of preclinical trials suggest that radiation therapy is a safe and effective treatment for restenosis after catheter-based vascular procedures. 192Ir treatment was designed to deliver a prescribed dose of 800 to 3000 cGy to the adventitial border. The patients were followed up for 3 years for revascularization of the target lesion and for safety parameters. Radiation therapy with catheter-based 192Ir shows good maintenance of clinical benefit at 3 years’ follow-up. There have been no major adverse events related to intravascular radiotherapy. A multitude of things have been proposed to decrease fibrointimal hyperplasia at sites of arterial injury, especially injury accompanying angioplasty. A recent recommendation has been the use of ionizing radiation. The authors haves always regarded this as something akin to using a howitzer to kill a mosquito. While you might indeed kill the mosquito, collateral damage may be significant.
Li N, Wallen H, Hjemdahl P (Karolinska Hosp, Stockholm)
Evidence for Prothrombotic Effects of Exercise and Limited Protection by Aspirin
Circulation 100:1374-1379, 1999
Previous studies have suggested that platelets and leukocytes may be activated in response to exercise, which thereby promotes thrombosis. Aspirin has known antithrombotic effects, but its influence on the prothrombotic effects of exercise are unclear. In healthy volunteers, exhaustive exercise is associated with platelet and leukocyte activation and with platelet-leukocyte aggregation. Platelet and leukocyte responses to in vitro stimulation are increased as well. Subjects pretreated with aspirin show reduced evidence of in vivo platelet activity at rest. It is widely accepted that vigorous exercise induces a prothrombotic state that may trigger an acute myocardial infarction, an observation well known to Dr Robert Barnes, who presciently observed that whenever he had the overwhelming desire to jog, he leaned against a tree until the desire passed. Physiologic alterations induced by strenuous exercise appear to involve the induction of thrombocytosis and platelet activation, as well as leucocytosis and leukocyte activation. While aspirin had some effect on this process, it did not improve exercise-induced increases in platelet aggregation or platelet leukocyte aggregation formation. On balance, the prothrombotic effect of exercise was little affected by aspirin. Certainly, we should not assume that we will be protected from an exercise-associated prothrombotic state by taking asprin.
Cole CR, Blackstone EH, Pashkow FJ, et al (Cleveland Clinic Found, Ohio)
Heart-Rate Recovery Immediately After Exercise as a Predictor of Mortality
N Engl J Med 341:1351-1357, 1999
Reduced vagal tone has a role in the increase in heart rate occurring during exercise. The reduction in heart rate that occurs immediately after exercise is related to vagal reactivation. Decreased vagal activity is associated with an increased risk of death. The heart rate reduction occurring from peak exercise to 1 minute after the end of exercise was assessed as heart rate recovery, and this value was correlated with overall morality. A heart rate recovery of 12 beats/min or less was considered abnormal.
A slow reduction in heart rate during the first minute after symptom-limited exercise is a significant predictor of overall mortality. This factor, possibly reflecting decreased vagal activity, is independent of exercise workload, myocardial perfusion defects, and exercise-induced increase in heart rate.
Isn’t this fascinating! A delayed decrease in heart rate during the first minute after the performance of a standard Bruce protocol treadmill test significantly predicted overall cardiac mortality and appeared to be independent of the level of exercise achieved, the presence or absence of myocardial perfusion defects, and the actual changes in heart rate during exercise. The extraordinarily simple-to-obtain data point may be valuable in the assessment of cardiac risk in routine clinical practice.
Hamroff G, Katz SD, Mancini D, et al (Albert Einstein College of Medicine, Bronx, NY)
Addition of Angiotensin II Receptor Blockade to Maximal Angiotensin-Converting Enzyme Inhibition Improves Exercise Capacity in Patients with Severe Congestive Heart Failure
Circulation 99:990-992, 1999
Incomplete suppression of the renin-angiotensin system during long-term angiotensin-converting enzyme (ACE) inhibition may enhance symptomatic deterioration in patients with severe congestive heart failure (CHF). The combination of angiotensin II type I (AT1) receptor blockage and ACE inhibition can suppress the activated renin-angiotensin system more efficiently than intervention alone in normal sodium-deleted patients. Losartan improves peak exercise capacity and eases symptoms in patients with CHF who are severely symptomatic, despite receiving maximally recommended or tolerated doses of ACE inhibitors. It appears that two drugs may be better than one. Robust evidence indicates that our aging cardiovascular patients are benefitted by suppression of the activated renin-angiotensin system. The addition of angiotensin I receptor blockade to maximal ACE inhibition markedly improved peak exercise performance and functional capacity in patients with congestive heart failure.
Tuomainen T-P, Kontula K, Nyyssonen K, et al (Univ of Kuopio, Finland; Univ of Helsinki)
Increased Risk of Acute Myocardial Infarction in Carriers of the Hemo-chromatosis Gene Cys282Tyr Mutation: A Prospective Cohort Study in Men in Eastern Finland
Circulation 100:1274-1279, 1999
Recent studies have suggested that most patients with hereditary hemochromatosis are homozygous for the Cys282Tyr mutation of the human hemochromatosis-associated gene (HFE). Elevated body iron stores are a risk factor for vascular disease. Men who are carriers of the relatively common HFE Cys282Tyr mutation are at double the risk for first acute MI. Hereditary hemochromatosis (HH) is one of the most frequently encountered inherited metabolic disorders. Several recent studies have identified increased body iron stores as an independent risk factor for acute MI. Iron-depleting treatment may contribute to primary prevention of MI. It is noteworthy that the causative link between HH and MI remains elusive.
Nappo F, De Rosa N, Marfella R, et al (Second Univ of Naples, Italy)
Impairment of Endothelial Functions by Acute Hyperhomocysteinemia and Reversal by Antioxidant Vitamins
JAMA 281:2113-2118, 1999
Cardiovascular disease risk is associated with increased concentrations of homocysteine, possibly through impairment of endothelial cell function. Mild to moderate increases in plasma homocysteine concentrations in healthy persons apparently activate coagulation, modify the adhesive properties of endothelium, and impair vascular responses to L-arginine. Antioxidant vitamin E and ascorbic acid pretreatment blocks the effects of hyperhomocysteinemia, indicating a possible oxidative mechanism.
Melissano G, Blasi F, Esposito G, et al (Scientific Inst (IRCCS) H San Raffaele, Milano, Italy; Univ of Milan, Milano, Italy)
Chlamydia pneumoniae Eradication From Carotid Plaques: Results of an Open, Randomised Treatment Study
Eur J Vasc Endovasc Surg 18:355-359, 1999
Chlamydia pneumoniae-induced atherosclerotic arterial wall degeneration has been documented in a rabbit model, and C pneumoniae infection has been linked to myocardial infarction in human beings. Whether roxithromycin can eradicate C pneumoniae from carotid artery plaques was tested in a prospective open randomized study. Roxithromycin reduced the bioburden in patients with C pneumoniae-infected atherosclerotic plaques. Extended studies are necessary to determine whether antibiotic treatment provides long-term benefits. The role of chronic infection in peptic ulcer disease has radically changed therapy for this condition in the last decade. Chronic infection has also been investigated as a potential influence in atherosclerotic plaque inflammation and rupture in the coronary and carotid circulation. Potential infecting agents include cytomegalovirus, Helicobacter pyroli, and Chlamydia pneumoniae. This small, randomized trial examined the effect of treating patients with antibiotics on organism burden in the plaque prior to carotid endarterectomy.
The authors continue to wonder if one day we will routinely prescribe antibiotics to alter the course of atherosclerosis in patients.
Boyer M, Townsend LE, Vogel LM, et al (William Beaumont Hosp, Royal Oak, Mich)
Isolation of Endothelial Cells and Their Progenitor Cells From Human Peripheral Blood
J Vasc Surg 31:181-189, 2000
There is interest in the possibility of using endothelial cells (ECs) to line small-diameter synthetic grafts. A technique of isolating EC progenitor cells for culture from peripheral and umbilical cord blood is reported. The successful isolation of EC progenitor cells from human peripheral or umbilical cord blood is demonstrated. These cells can subsequently be cultured into ECs, to be used for lining vascular grafts or for gene therapy. These techniques may be a key step in the development of a small-diameter vascular graft. If one thing seems clear, it is that the peripheral blood monocyte can become almost any cell in the body. The immediate ability to have a reliable source of endothelial cells for other studies will be an asset to laboratory investigation.
Chen C-H, Jiang W, Via DP, et al (Baylor College of Medicine, Houston; Natl Taiwan Univ, Taipei)
Oxidized Low-Density Lipoproteins Inhibit Endothelial Cell Proliferation by Suppressing Basic Fibroblast Growth Factor Expression
Circulation 101:171-177, 2000
In vitro studies have demonstrated inhibited endothelial cell (EC) proliferation in the presence of hyperlipidemia. If the mechanism by which hyperlipidemia impairs endothelial function could not be understood, it might lead to new antiatherosclerotic therapies. The role of basic fibroblast growth factor (bFGF) in inhibiting EC function in response to oxidized low-density lipoproteins (ox-LDLs) was examined. Reduced bFGF expression is at least 1 mechanism by which ox-LDLs exert cytotoxic effects on ECs. The inhibitory effect of hyperlipidemia on angiogenesis appears related to reduced availability of bFGF and can be corrected by exogenous bFGF treatment. It appears clear that hyperlipidemia, especially hyperchlolesterolemia, impairs both large-vessel and microvascular endothelial function, as well as angiogenesis. There is some evidence that hyperlipidemia reduces bFGF concentration, which may be a causative mechanism. Cytotoxic effects of ox-LDLs on ECs resulted, in significant part, from suppression of bFGF expression. This is an interesting preliminary observation, that may have real clinical importance.
McCarthy MJ, Loftus IM, Thomson MM, et al (Univ of Leicester, England)
Angiogenesis and the Atherosclerotic Carotid Plaque: An Association Between Symptomatology and Plaque Morphology
J Vasc Surg 30:261-268, 1999
Patients with symptomatic carotid artery stenosis caused by thromboembolism may have unstable plaque and intraplaque hemorrhage. These factors of the artherosclerotic plaque may be related to the fragility and position of neovessels within the plaque. The group with symptoms showed larger and more irregular plaques, with a significantly higher prevalence of plaque necrosis and rupture. The finding of plaque hemorrhage and rupture was related to a number of neovessels within the plaque and within the fibrous cap. The neovessels are larger and more irregular in vessels associated with symptoms, which may paly a role in plaque instability and the development of thromboembolic sequelae. This article is fascinating. Similar to coronary atherosclerosis, symptomatic carotid plaque is morphologically different from asymptomatic plaque. Neovascularization was not only more frequent in symptomatic plaques, but the neovessels were larger and more irregularly shaped. The study also suggested that neurologic sequelae could be possibly ameliorated by stabilization of the plaque neovessels.
Takase S, Schmid-Schonbein G, Bergan JJ (Univ of California, San Diego)
Leukocyte Activation in Patients With Venous Insufficiency
J Vasc Surg 30:148-156, 1999
Activated monocytes on venous endothelium may migrate into the venous wall, resulting in toxic metabolites and free oxygen radicals that may contribute to valve destruction and venous wall weakening. The degree to which leukocytes are activated in patients is unknown. Activated neutrophil levels were lower in patient whole blood than in healthy blood incubated in patient plasma, suggesting that activated neutrophils in patients with chronic venous insufficiency may be trapped in the peripheral circulation. Which plasma factors induce activation of naïve neutrophils is unknown, but such activators may be important in the pathogenesis of primary venous dysfunction and the development of chronic venous insufficiency.
Raffetto JD, Mendez MV, Phillips TJ, et al (Boston Univ)
The Effect of Passage Number on Fibroblast Cellular Senescence in Patients With Chronic Venous Insufficiency With and Without Ulcer
Am J Surg 178:107-112, 1999
In vitro, cellular senescence is associated with progressive loss of proliferative capacity as passage number increases. This event has been linked to impaired healing in vivo. In vitro passage of distal and proximal fibroblasts from patients with chronic venous ulcers appears to have a significant impact on doubling time and cellular senescence. Accumulation of senescent fibroblasts and more advanced cellular senescence of distal fibroblasts may explain the treatment resistance observed in repeated episodes of venous ulceration. The evidence seemed to be conclusive in indicating that fibroblasts from venous ulcers simply did not divide in a normal fashion and thus did not lead to normal wound healing. This, of course, does not mean that such wounds will not heal but simply that they are more difficult to heal. Perhaps one day we will have a substance that will counteract the negative effect of the wound environment on healing and actually promote fibroblast division. To date, nothing has proved superior to gauze pads and elastic compression stockings.
Slonim SM, Miller DC, Mitchell RS, et al (Stanford Univ, Calif; Palo Alto Veterans Administration Med Ctr, Calif)
Percutaneous Balloon Fenestration and Stenting for Life-Threatening Ischemic Complications in Patients With Acute Aortic Dissection
J Thorac Cardiovasc Surg 117:1118-1127, 1999
Ischemic complications of aortic dissection carry a mortality rate of 60% or greater. The intervention consisted of stenting of the true or false lumen combined with balloon fenestration of the intimal flap. These percutaneous procedures make possible reperfusion of isschemic regions without the morbidity of major vascular surgery. Percutaneous methods were potentially safer and more successful than surgery. There is simply no doubt that a skilled interventional expert can achieve catheter-based reperfusion of organs and limbs in acute dissection with a high rate of success.
De Virgilio C, Bui H, Donayre C, et al (Harbor-UCLA Med-Ctr, Torrance, Calif; West Los Angeles Veterans Affairs Med Ctr, Los Angeles)
Endovascular vs Open Abdominal Aortic Aneursym Repair: A Comparison of Cardiac Morbidity and Mortality
Arch Surg 134:947-951, 1999
The rates of adverse cardiac events are similar for both endovascular and open abdominal aortic aneurysm repair. The Eagle criteria – age greater than 70 years; history of diabetes, angina, and congestive heart failure; Q wave on electrocardiogram; and venticular ectopy – were applied to prospectively assess patients undergoing EAAA and to retrospectively evaluate patients who had open abdominal aortic aneurysm (OAAA) repair. The main outcome measures were myocardial infarction, congestive heart failure, and cardiac death. The rates of cardiac events and mortality were similar for patients undergoing EAAA and OAAA repair. A history of congestive heart failure and Q wave on the preoperative electrodiogram were predictive of adverse cardiac events for both groups.
Liu AY, Paulsen RD, Marcellus ML, et al (Stanford Univ, Calif)
Long-term Outcomes After Carotid Stent Placement for Treatment of Carotid Artery Dissection
Neurosurgery 45:1368-1374, 1999
Endovascular stent repair of carotid artery dissections can now be performed successfully. For patients with extracranial carotid artery dissection, stent placement provides good long-term results. The stents remain patent and the patients free of symptoms. In our practice, we see only a few patients with carotid dissection per year, and so far they have responded well to anticoagulation alone, without the need for intraluminal stent placement.
Qureshi Al, Luft AR, Janardhan V, et al (State of New York, Buffalo)
Identification of Patients at Risk for Periprocedural Neurological Deficits Associated With Carotid Angioplasty and Stenting
Stroke 31:376-382, 2000
Patients undergoing carotid angioplasty and stenting (CAS) are at a risk of transient or permanent neurologic deficits developing during or after the procedure. The authors’ conclusion that the occurrence of neurologic deficits was more likely in patients with symptomatic lesions or long-segment lesions is hardly suprising. The potential to do harm through distal embolization is so great that, despite innovative efforts to devise gadgets to minimize distal embolization, the procedure of carotid artery angioplasty and stenting is never going to be an acceptable alternative to well-performed carotid surgery.
Erbel R, for the Restenosis Stent Study Group (Univ of Essen, Germany; et al)
Coronary-Artery Stenting Compared With Balloon Angioplasty for Restenosis After Initial Balloon Angioplasty
N Engl J Med 339:1672-1678, 1998
Restenosis after coronary balloon angioplasty occurs in 30% to 50% of patients. Stent implantation in patients with new coronary stenosis is known to reduce the restenosis rate. Compared with standard balloon angioplasty, coronary stent palcement had a higher clinical success rate, a lower incidence of restenosis and revascularization at 6 months, and a lower rate of cardiac events. The rate of bleeding complications was higher. Stents for iliac arteries is not helpful; and angioplasty with or without a stent for renal arteries is generally meddlesome, as medical treatment appears equally effective. This article refers to the treatment of restenosis. The author does not know whether this material could not be extrapolated to treatment of primary stenosis.
Giannoukas AD, Tsetis DK, Touloupakis E, et al (Univ of Crete, Heraklion, Greece)
Suppurative Bacterial Endarteritis After percutaneous Transluminal Angioplasty, Stenting and Thrombolysis for Femoropopliteal Arterial Occlusive Disease
Eur J Vasc Endovasc Surg 18:455-457, 1999
Femoropopliteal occlusive disease can be treated by endovascular techniques. Closure within the first month is a potential problem, but there have been few reports of septic complications. Acute thrombolysis is a potential complication of percutaneous transluminal angioplasty and stenting of the femoropopliteal artery. If thrombolysis is performed, it should be achieved over less than 24 hours, if possible. Careful attention should be given to the catheter entry site and to sterile technique. Patients with vascular endoprosthesis are at risk for septic complications and may benefit from prophylactic antibiotics. The purpose of this case presentation is to demonstrate the frightful potential for a supportive arteritis after angioplasty and stent placement.
Fawzy ME, Sivanandam V, Pieters F, et al (King Faisal Specialist Hosp, Riyadh, Saudi Arabia)
Long-term Effects of Balloon Angioplasty on Systematic Hypertension in Adolescent and Adult Patients With Coarctation of the Aorta
Eur Heart J 20:827-832, 1999
The results of balloon coarctation angioplasty, which is now an accepted alternative treatment for aortic coarctation in infants and children, have also been promising in adolescents and adults. Blood pressure normalized without medication after angioplasty in 74% of these patients with aortic coarctation, with subsequent long-term regression of left ventricular hypertrophy. For adolescents and adults, balloon angioplasty should be considered the first-line treatment for native, discrete aortic coarctation.
Goertler M, Baeumer M, Kross R, et al (Univ of Magdeburg, Germany)
Rapid Decline of Cerebral Microemboli of Arterial Origin After Intravenous Acetylsalicylic acid
Stroke 30:66-69, 1999
Among patients with carotid artery stenosis, the transcranial Doppler (TCD) sonographic finding of microembolic signals (MES) reflects platelet and fibrin particles coming from the stenotic lesion. Acetylsalicylic acid (ASA) therapy, alone or with carotid surgery, reduces cerebral embolism by means of cyclo-oxygenase pathway – related platelet inhibition. After 1 hour of TCD monitoring, each patient received an IV bolus injection of ASA 500 mg, followed by an additional 2.5 hours of TCD monitoring. The patients also underwent 1 hour of TCD monitoring the next day. Intravenous ASA significantly reduces the MES rate in patients with recent arterial stroke. Monitoring of microemboli with TCD might be useful indicator of the early effects of antiplatelet therapy for these patients. Actual temporal association between the administration of aspirin and the cessation of microemboli in the middle cerebral artery absolutely fascinating.
De Cobelli F, Venturini M, Vanzulli A, et al (Univ Hosp, Milan, Italy; Multimedia Hosp, Milan, Italy)
Renal Arterial Stenosis: Prospective Comparison of Color Doppler US and Breath-Hold, Three-Dimensional, Dynamic, Gadolinium-Enhanced MR Angiography
Radiology 214:373-380, 2000
Noninvasive imaging studies for the detection of renal arterial stenosis include color Doppler US and MR angiography. The findings support the use of MR angiography over color Doppler US for the detection of accessory renal arteries in patients with suspected renal arterial stenosis. The 2 techniques offer similar diagnostic specificity. The is developing grave reservations as to the importance of detecting renal artery stenosis by vascualr surgery or interventional radiology. New studies are now beginning to indicate that the medical treatment of hypertension is as effective as any interventional efforts.
Yusuf S, and the Heart Outcomes Prevention Evaluation Study Investigators (Canadian Cardiovascular Collaboration Project, Hamilton, Ont, Canada; et al)
Effects of an Angiotensin-Converting-Enzyme Inhibitor, Ramipril, on Cardiovascular Events in High-Risk Patients
N Engl J Med 342:145-153, 2000
Patients with left ventricular dysfunction benefit from angiotensin-converting enzyme (ACE) inhibitor therapy, regardless of the presence or absence of heart failure. The analysis included 9297 patients aged 55 years or older. They were randomized to receive the ACE inhibitor ramipril or placebo and vitamin E supplementation or placebo. The ramipril dose was 10 mg once daily; treatment continued for a mean of 5 years. The effects of ramipril were assessed in terms of a composite end point of myocardial infarction, stroke, and death from cardiovascular causes. Treatment with an ACE inhibitor significantly reduces the risk of cardiovascular events and death in patients who are at high risk for, but do not have, left ventricular dysfunction or heart failure. This study presents dramatic information describing the remarkable effects of the routine administration of ACE inhibitors on the occurrence of cardiovascular morbid events in a huge number of high-risk patients randomly assigned to ACE inhibitor or placebo. The author believes there is presently persuasive evidence that coronary patients should receive routine ACE inhibitor therapy.
Poldermans D, for the Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography Study Group (Erasmus Med Ctr, Rotterdam; et al)
The Effect of Bisoprolol on Perioperative Mortality and Myocardial Infarction in High-Risk Patients Undergoing Vascular Surgery
N Engl J Med 341:1789-1794, 1999
Fatal and nonfatal myocardial infarctions are serious potential complications in patients undergoing major vascular surgical procedures. For selected high-risk patients undergoing major vascular surgery, b-blockade with bisoprolol significantly reduces the risk of cardiac death and nonfatal myocardial infarction. High-risk patients can be defined by the presence of 1 or more cardiac risk factors plus a positive result on dobutamine stress echocardiography. The present study documents significant reductions in both the rates of cardiac-related death and nonfatal myocardial infarction in high-risk patients undergoing elective abdominal aortic aneurysm or infrainguinal bypass operations associated with the use of b-blockade. b-blockade is simple and effective in reducing perioperative cardiac events and is likely to show a significantly better cost-benefit ratio in patients requiring peripheral vascular surgery than exhaustive cardiac evaluations and prophylactic cardiac interventions.
Kontos MC, Jesse RL, Anderson FP, et al (Virginia Commonwealth Univ, Richmond)
Comparison of Myocardial Perfusion Imaging and Cardiac Troponin I in Patients Admitted to the Emergency Department With Chest Pain
Circulation 99:2073-2078, 1999
Emergency department (ED) diagnosis of patients with acute coronary syndromes (ACSs) poses a challenging problem. Sensitivity for the diagnosis of myocardial infarction was 92% for MPI and 90% for serial cTnI. Troponin determination has replaced CPK-MB. Without question, this article reaffirms the value of serum troponin in the diagnosis of myocardial infarction.
Brown WR, Moody DM, Challa VR, et al (Wake Forest Univ, Winston-Salem, NC)
Longer Duration of Cardiopulmonary Bypass Is Associated With Greater Numbers of Cerebral Microemboli
Stroke 31:707-713, 2000
Microemboli are believed to contribute to the occurrence of cerebral injury after cardiopulmonary bypass (CPB). Embolic load was greater for subjects with a longer duration of CPB: a 90.5% increase in embolic load per 1-hour increase in duration of CPB. The results suggest that eliminating the use of scavenged blood or removing lipid emboli from such blood may reduce the risk of postbypass cerebral injury. All patients experience cerebral embolic events caused by CPB. Thousands of microemboli were found in the brains of these patients. We must accept that CPB is risky business. Patients are not really normal after this experience. While you may think you are doing your patient a favor by recommending prophylactic coronary artery bypass grafting for repair of asymptomatic coronary lesions, the reality is you may well be doing the opposite.
Yusuf S, for the Heart Ouctomes Prevention Evaluation Study Investigators (Hamilton Gen Hosp, Ont, Canada; et al)
Vitamin E Supplementation and Cardiovascular Events in High-Risk Patients
N Engl J Med 342:154-160, 2000
Previous studies have suggested that vitamin E supplementation reduces the risk of coronary heart disease and atherosclerosis. Vitamin E supplementation does not reduce the cardiovascular event rate in patients at high risk. The lack of effect occurred despite 4 to 6 years of treatment with a high dose of vitamin E. Many nutritionists have preached for years that the ingestion of vitamin E is associated with beneficial clinical effects. Sadly, treatment of patients at high risk for cardiovascular events with vitamin E for a mean of 4.5 years had absolutely no measurable beneficial effect compared with placebo. The author does believe that this should definitively lie to rest the myth that vitamin E has beneficial cardiovascular effects. In fact, to date, the clinical benefit of the use of antioxidants has been nil.
Wolowczyk L, Williams AJ, Donovan KL, et al (Morriston Hosp, Swansea, Wales)
The Snuffbox Arteriovenous Fistula for Vascular Access
Eur J Vasc Endovasc Surg 19:70-76, 2000
For patients who require hemodialysis, the initial arteriovenous (AV) fistula should be placed as distally as possible. This provides a long segment of arterialized vein for venipuncture, while providing for creation of a more proximal fistula in case the first becomes occluded. The snuff-box AV fistula offers important advantages as the initial route of vascular access for patients requiring hemodialysis. The anatomical snuff-box is a convenient place to attempt an end-to-side fistula between the cephalic vein and the radial artery. A very respectable 80% of such fistulas could be used for dialysis within 6 weeks. The patency rate was 65% at 1 year and a remarkable 45% at 5 years. The authors are absolutely correct in recommending that we consider a more widespread clinical use of the snuff-box AV fistula.
Livingston CK, Potts JR III (Univ of Texas, Houston)
Upper Arm Arteriovenous Fistulas as a Reliable Access Alternative For Patients Requiring Chronic Hemodialysis
Am Surg 65:1038-1042, 1999
The radial artery-cephalic vein (CV) wrist fistula has long been the preferred access site for hemodialysis. For patients with unsuitable wrist anatomy for CV fistula creation, upper-arm AVFs provide a useful alternative. Upper arm AVFs should be considered before vascular graft placement is performed. Upper arm AVFs should be considered before graft placement if wrist and forearm anatomy do not make the wrist Brescia-Cimino appear attractive.
Link J, Steffens JC, Brossmann J, et al (Christian-Albrechts-Univ of Kiel, Germay; Siemens Med Systems, Hamburg, Germany)
Iliofemoral Arterial Occlusive Disease: Contrast-Enhanced MR Angiography for Preinterventional Evaluation and Follow-up After Stent Placement
Radiology 212: 371-377, 1999
This study assesses the findings of contrast-enhanced MR angiography in patients with peripheral arterial occlusion and its use for follow up after stent placements.
Of 67 patients referred for evaluation of iliofemoral occlusive disease. 28 underwent pre-interventional DSA and contrast enhanced MRA. 39 patients were studied after stent placements.
The diagnostic accuracy of the MRA was 100% for occlusions. It had 100% sensitivity in the diagnosis of stenosis more than 50%, with a specificity of 83%. It was also accurate for demonstrating stent patency. There were problems with signal intensity drop out.
Ascher E, Mazzariol F, Hingorani A, et al (Maimonides Med CTr, Brooklyn, NY)
The Use of Duplex Ultrasound Arterial Mapping as an Alternative to Conventional Arteriography for Primary and Secondary Infrapopliteal Bypasses
Am J Surg 178: 162-165, 1999
This study compares the use of duplex ultrasound (DUAM) with the use of contrast angiography (CA) for infra inguinal imaging (arterial mapping) for primary and secondary infrapopliteal bypasses.
26 such bypasses were performed on the basis of DUAM only, and in 2 cases a CA was also done. Bypasses originated from external iliac artery (3), femoral artery (17), popliteal artery (4), and from a previous graft in 4. The distal anastomosis was to the posterior tibial (7), anterior tibial (6), peroneal (3), and dorsalis pedis in 12 cases.
DUAM identified a single infrapopliteal run off artery in 22 patients. 2 such arteries in 4 patients, and 3 in 2 patients. Completion arteriography matched DUAM findings in 96% of patients. In one case a significant anterior tibial artery stenosis was missed by DUAM.
DUAM is a safe alternative to invasive CA for infrainguinal arterial occlusive disease.
Pahlsson H-I, Wahlberg E, Olofsson P, et al (Univ Hosp, Linkoping, Sweden; Karolinksa Hosp, Stockholm)
The Toe Pole Test for Evaluation of Arterial Insufficiency in Diabetic Patients
Eur J Vasc Endovasc Surg 18: 133-137, 1999
The efficacy of the pole test at the toe level for determining arterial insufficiency in diabetics was assessed in a prospective study.
The test has been described. It was used in 23 patients (25 legs).
In 44% of the legs, the cuff measurements at the ankle level was compared with the pole test. The cuff measurements were significantly higher. In 13 out of the remaining 14, maximal elevation did not cause the Doppler signal to disappear. At the toe level, the two methods did not differ significantly.
This test can be used at the toe level to assess arterial insufficiency.
Taylor BS, Rhee RY, Muluk S, et al (Univ of Pittsburgh, Pa)
Thrombin Injection Versus Compression of Femoral Artery Pseudoaneurysms
J Vasc Surg 30: 1052-1059, 1999
A 3 year experience with compression and thrombin injection for the treatment of femoral artery pseudoaneurysms is presented.
40 patients of femoral artery pseudoaneurysm treated with ultrasound guided compression therapy are compared with 23 patients primarily treated with dilute thrombin injection.
The success rate of US-guided compression was 63% as against 91% by thrombin injection. Out of the failures of US-guided compression therapy, 6 were successfully treated by thrombin injection. The time taken was also shorter (a few seconds versus 37 minutes with the US-guided compression). The costs were also lower.
Thrombin injection is safe, quick, painless and has a high success rate.
Eidt JF, Habibipour S, Saucedo JF, et al (Univ of Arkansas For Med Sciences, Little Rock; John L McClellan VAMC, Little Rock, Ark)
Surgical Complications From Hemostatic Puncture Closure Devices
Am J Surg 178: 511-516, 1999
These devices seek to provide prompt hemostasis even in patients on anticoagulation. An experience with the Angio-Seal hemostatic puncture device is presented.
All vascular complications related to femoral cardiac catheterization in a vascular surgery service were reviewed over a period of one year. Groin complications were identified and medical device reports for each of the 3 approved hemostatic puncture closure devices were obtained.
There was an 8% rate of immediate mechanical failure (425 patients and 1662 uses in all). The rates of surgical repair were 1.6%. 5 patients experienced occlusion or stenosis of the femoral vein. In one case the polymer anchor became embolized and had to be retrieved by a balloon catheter.
Gonze MD, Sternbergh WC III, Salartash K, et al (Ochsner Med Institutions, New Orleans, La)
Complications Associated With Percutaneous Closure Devices
Am J Surg 178: 209-211, 1999
These new devices introduced to facilitate hemostasis after angiography are not without risk. Unique complications of these devices are presented.
Data was collected on the Angio-Seal device, the Prostar XL percutaneous vascular surgical device and the Duet sealing device.
During the study period these devices were used in 408 (19%) of 2181 patients. There were 10 (2.5%) complications – local erythema and subcutaneous abscess in 4, a pseudoaneurysm in 4 and 3 became hemodynamically unstable requiring resuscitation.
Percutaneous closure devices reduce time to hemostasis after angiography but complications can occur and surgeons need to be aware of deployment mechanisms to treat complications.
Abou-Zamzam AM Jr, Moneta GL, Edwards JM, et al (Oregon Health Sciences Univ, Portland; Portland VA Med Ctr, Oregon)
Is a Single Preoperative Duplex Scan Sufficient for Planning Bilateral Carotid Endarterectomy ?
J Vasc Surg 31: 282-288, 2000
The effects of unilateral carotid endarterectomy (CEA) on the duplex scan findings in the contralateral ICA were reviewed for patients with bilateral carotid stenosis.
Pre and postoperative carotid duplex scans obtained within 6 months after CEA were analyzed for 460 patients. Changes in the peak systolic velocity (PSV) and end-diastolic velocity (EDV) were recorded, percent stenosis was determined and the effects of PSV and EDV, indication for CEA, degree of stenosis in ICAs managed with or without CEA, on the changes in classification of contralateral ICA stenosis were analyzed.
Approximately 20% of patients showed reduction in stenosis of contralateral ICA on postoperative duplex scanning.
Jmor S, EI-Atrozy T, Griffin M, et al (Imperial College School of Medicine at St Mary’s London)
Grading Internal Carotid Artery Stenosis Using B-Mode Ultrasound: (In Vivo Study)
Eur J Vasc Endovasc Surg 18: 315-322, 1999
With modern techniques, B-mode US could provide an important alternative for grading carotid stenosis. The use of percentage area and diameter reduction were evaluated in grading ICA stenosis with color-coded B-mode transverse US.
The percentage area reduction of the in vivo measurements was related in linear fashion to the specimen measurements. The in vivo duplex measurements had a 95% confidence interval of 8% (95% CI diameter reduction, 5%).
Duplex scanning (B-mode) provides an accurate method of measuring the degree of carotid stenosis. This may become the main criterion for duplex scanning with velocity measurements used as secondary criteria.
Feinglass J, Brown JL, LoSasso A, et al (Northwestern Univ)
Rates of Lower-Extremity Amputation and Arterial Reconstruction in the United States, 1979 to 1996
Am J Public Health 89: 1222-1227, 1999
Previous reports have indicated high arterial patency rates in patients undergoing vascular surgery for lower extremity ischemia.
The data from national surveys were used to assess trends in lower extremity amputation and revascularization procedures and risk factors for vascular disease.
The major amputation rate increased by about 11% between 1979-1980 and 1995-1996 despite a reduction between 1983-1984 and 1991-1992 probably due to reduction in smoking, hypertension and heart disease but not in diabetes. The rates of amputation and angioplasty were inversely co-related.
National data suggests that the decrease in major amputation occurred after an increase in the rate of distal bypass surgery but before the use of angioplasties. Risk factor reduction may be responsible for reduction in amputation rates.
Nehler MR, Whitehill TA, Bowers SP, et al (Univ of Colorado, Denver)
Intermediate-term Outcome of Primary Digit Amputations in Patients With Diabetes Mellitus Who Have Forefoot Sepsis Requiring Hospitalization and Presumed Adequate Circulatory Status
J Vasc Surg 30: 509-518, 1999
Diabetic foot lesions account for about 60% of all nontraumatic amputations. Aggressive revascularization is widely accepted for forefoot lesions and critical ischemia. Limb salvage success is often accompanied by morbidity. The intermediate success rate and outcome of primary forefoot amputation has been evaluated.
A retrospective study of 92 patients with 97 forefoot infections has been done. All patients required hospitalization for digit amputation. All had adequate arterial circulation based on clinical and non invasive evaluations.
A primary digit amputation was performed followed if necessary by debridement (97 primary digit amputations, 34 through i-p joints, 28 through metatarsal heads and 35 through metatarsal shafts).
The median hospital stay was 10 days. 39% healed in 13 weeks, 24% did not heal. In 36% the infection persisted and infection recurred in 40%.
Twenty two foot amputations had to be performed.
Patients with diabetes mellitus have a high rate of intermediate term persistent and recurrent infection associated with a modest rate of limb loss.
Ubbink DT, Spincemaille GHJJ, Reneman RS, et al (Academic Med Ctr, Amsterdam; De Wever Hosp, Heerlen, The Netherlands; Cardiovascular Research Inst, Maastricht, The Netherlands)
Prediction of Imminent Amputation in Patients With Non-reconstructible Leg Ischemia by Means of Microcirculatory Investigations
J Vasc Surg 30: 114-121, 1999
The usefulness of microcirculatory parameters in predicting imminent amputation was assessed prospectively in patients with critical ischemia by correlating these parameters with the patients clinical outcome.
111 patients with critical ischemia of one of the lower limbs with persistent rest pain, a Doppler ankle systolic pressure of < 50 mm Hg or an ankle/brachial pressure index of < 0.35 were managed with optimum conservative medical treatment with or without spinal cord stimulation.
Clinical examination and non-invasive investigations were repeated at 1, 3, 6, 12 and 18 months with a follow up of 36 months. The end point was major amputation.
The microcirculatory data was classified as follows: 30 (poor skin perfusion), 63 (intermediate), and 10 (good skin perfusion).
The incidence of amputation was significantly higher in those with poor skin perfusion than in the other 2 groups.
The positive and negative predictive values of microcirculatory studies were 73% and 67% respectively. Cumulative limb survival rates at 6 and 12 months were 26% and 15% in the poor microcirculation group, 80% and 63% in the intermediate group and 88% and 88% in the good group. All differences were significant.
Seeger JM, Pretus HA, Carlton LC, et al (Univ of Florida, Gainesville)
Potential Predictors of Outcome in Patients With Tissue Loss Who Undergo Infrainguinal Vein Bypass Grafting
J Vasc Surg 30: 427-435, 1999
Two hundred and ten patients who underwent infrainguinal vein bypass grafting for ischemic tissue loss were evaluated retrospectively to determine the incidence rate of a bad outcome and to identify predictors of poor outcome and subsets of patients who were likely to have less-than-optimal results.
A blind review of duplex scan venous mapping and arteriography was performed for 125 patients (who had undergone bypass grafting to the popliteal, infrapopliteal and pedal arteries) to determine simplified view and run-off scores.
Outcome measures included influence of risk factors, venous conduit and run off on mortality, limb loss and graft failure at 6 month follow up.
During follow up, 9.1% of patients died, 15.8% underwent amputations (more frequently in diabetics) and 81% had limb salvage surgery. The run off score was the strongest predictor of outcome.
The aggressive use of infrainguinal vein bypass surgery for ischemic tissue loss results in a high rate of initial limb salvage but also causes significant morbidity and mortality. The run off scores (by anteriography) are the best predictions of outcome.
Huber TS, Wang JG, Wheeler KG, et al (Univ of Florida, Gainesville; Duke Univ, Durham, NC; et al)
Impact of Race on the Treatment for Peripheral Arterial Occlusive Disease
J Vasc Surg 30: 417-426, 1999
African Americans are significantly less likely to suffer from peripheral arterial occlusive disease (PAOD) than white patients. The effects of race on treatment of PAOD, the role of access to care and disease distribution were examined retrospectively.
Data from 202 nonfederal acute care hospitals were analyzed. Patients over 44 years of age underwent major lower extremity amputation or revascularization because of PAOD. The primary outcome measures were incidence of intervention, incidence per demographic group, multivariate predictors of amputation versus revascularization among patients with access to sophisticated care, and multivariate predictors of surgical bypass graft type.
During a 3 year period 51,819 procedures (9.1 per 10,000 population) were performed including 15,579 major lower extremity amputations i.e. 30.1% and 36,240 revascularization (69.9%). The rate of a procedure being performed for PAOD was comparable between the 2 races but the rate of amputation was higher and that of revascularization was lower in the African Americans.
Noticeable racial disparity was observed in the treatment of patients with PAOD. This may partially be explained by differences in disease severity or disease distribution.
Berceli SA, Chan AK, Pomposelli FB Jr, et al (Harvard Med School, Boston)
Efficacy of Dorsal Pedal Artery Bypass in Limb Salvage for Ischemic Heel Ulcers
J Vasc Surg 30: 499-508, 1999
The role of pedal artery bypass in the treatment of heel ulceration (ischemic) is examined.
A retrospective analysis of 432 bypass grafts performed for ischemic gangrene or ulceration was done. 336 of these procedures were in the forefoot and 96 in the heel. Digital angiography was used before surgery to determine revascularization options, and to find out whether there was a connection between the dorsal and plantar circulation.
The rates of healing were similar in both groups. The rates of major lower extremity amputation were also similar. The rates of healing and graft patency were independent of the presence of an intact arch.
Substantial perfusion to the posterior foot is gained with the dorsal pedal artery bypass graft. The limb salvage and healing rates for revascularized heel lesions are comparable to rates found in ischemic forefoot pathology.
L. R. Jiao, A. M. Seifalian, B. R. Davidson and N. Habib (Liver Surgery Unit, Imperial College School of Medicine, Hammersmith Hospital and University Department of Surgery, Royal Free and University College Medical School, London, UK)
In Vivo Evaluation of an Implantable Portal Pump System for Augmenting Liver Perfusion
Br J. Surg August 2000 Vol. 87 (8) Pg. 1024-1029
Increasing portal inflow in cirrhosis using a mechanical pump reduces portal venous pressure and improves liver function. A pump has been developed for portal vein implantation in human cirrhosis. This study describes the initial in vivo evaluation in a porcine model.
It is technically possible and safe to insert an implantable pump in the portal vein. Portal venous blood flow can be increased up to 50 per cent with a resultant increase in flow in the hepatic microcirculation and hepatic oxygenation and without adverse effects on either hepatic or systemic haemodynamics.
Although these studies on bench-perfused cirrhotic livers may not reflect in vivo findings, similar results have recently been demonstrated in animal models with portal hypertension and extensive hepatic fibrosis. Short-term mechanical pumping of portal inflow to the human cirrhotic liver in vivo in patients undergoing orthotopic liver transplantation demonstrated similar results.
Following the enhanced portal inflow, macroscopic and microscopic examination of biopsies taken from the liver, small bowel and spleen showed no evidence of ischaemic change or morphological damage. No intrahepatic thrombosis was seen.
Blood flow in the portal vein is of low frequency waveform and non-pulsatile. Mechanical pumping of portal venous blood on the other hand produced a pulsatile portal venous flow similar to that of the hepatic artery. This alteration of the normal flow pattern in the portal vein may be a beneficial factor in the perfusion of the cirrhotic liver and for the prevention of venous thrombosis.
In liver cirrhosis there is abnormal hepatic microcirculation and decreased substance diffusion through sinusoids as a result of capillarization. With improved hepatic microcirculation and tissue oxygenation, an improvement in liver function might be expected in patients with cirrhosis.
Portal vein flow augmentation has been shown to reduce portal vein pressure in a perfused cirrhotic animal model, suggesting a possible role in reducing variceal pressure and prevention of haemorrhage.
Most of the drugs used for treatment of portal hypertension interfere with the systemic circulation leading to a reduction in cardiac output and worsening of renal function. If reproducible in humans, the avoidance of systemic upset by portal flow augmentation would have many advantages over drug therapy for portal hypertension.
The insertion of the portal pump was achieved in this experiment by laparotomy and a venotomy. In patients with cirrhosis or portal hypertension laparotomy is associated with significant mortality and morbidity, and damage to the portal vein may prohibit liver transplantation. The developers are pursuing the option of percutaneous or transjugular insertion.
Caprini JA, Arcelus JI, Motykie G, et al (Evanston Northwestern Healthcare, III; Northwestern Univ, Chicago; Hospital de la Axarquia Velez-Malaga, Malaga, Spain)
The Influence of Oral Anticoagulation Therapy on Deep Vein Thrombosis Rates Four Weeks After Total Hip Replacement
J Vasc Surg 30: 813-820, 1999
The influence of oral anticoagulation therapy on deep vein thrombosis (DVT) rates four weeks after total hip replacement (THR).
There is no consensus on the period of anticoagulation therapy required after THR. The incidence of DVT in the first month after THR was evaluated in patients receiving warfarin therapy and compression stockings.
125 patients were studied. All were given pneumatic compression over elastic stockings throughout the postoperative period. Postoperative heparin therapy was followed by warfarin orally. This was continued after discharge from the hospital for 1 month.
15% of cases showed DVT. About 1/3rd were detected at the end of one week and 2/3rds at the end of 4 weeks. Proximal DVT was seen in 2% (at 1 week) and 8% (at 1 month). 64% were asymptomatic.
Patients with DVT had significantly lower INR (international normalized rates) values than those without DVT.
Post THR the risk of DVT is significant for the first month even with anticoagulation therapy. The anticoagulation therapy must be continued for at least 1 month postoperatively.
Hull RD, Brant RF, Pineo GF, et al (Univ of Calgary, Alta, Canada; Henry Ford Hosp, Detroit; Univ of Oklahoma, Oklahoma City)
Preoperative vs Postoperative Initiation of Low-Molecular-Weight Heparin Prophylaxis Against Venous Thromboembolism in Patients Undergoing Elective Hip Replacement
Arch Intern Med 159: 137-141, 1999
This study is a meta-analysis of preoperative versus postoperative initiation of prophylactic LMWH therapy in patients undergoing hip replacement surgery.
Ten randomized trials have been analyzed. Patients were given enoxaparin for DVT prophylaxis either pre or post operatively (level 1 trials). DVT was evaluated by direct contrast ascending venography.
With preoperative enoxaparin 10% had DVT whereas it was 15% in those who received postoperative LMWH therapy. The rate of major bleeding episodes was also lower with preoperative LMWH therapy (0.9% versus 3.5%). Preoperative LMWH prophylaxis gives better results.
Blanchard J, Meuwly J-Y, Leyvraz P-F, et al (Hopital Orthopedique de la Suisse Romande, Lausanne, Switzerland; Universitaire de Geneve, Geneva, Switzerland)
Prevention of Deep-Vein Thrombosis After Total Knee Replacement: Randomised Comparison Between a Low-Molecular-Weight Heparin (Nadroparin) and Mechanical Prophylaxis With A Foot-Pump System
J Bone Joint Surg Br 81-B: 654-659, 1999
This study compares intermittent pneumatic compression versus LMWH prophylaxis for prevention of DVT after TKA.
130 patients undergoing elective TKA were analyzed. One group received nadroparin calcium as a subcutaneous injection daily. The other group underwent continuous intermittent pneumatic compression of the foot with the arteriovenous impulse system. DVT was assessed by phlebography 8-12 days postoperatively on 108 patients. Bleeding and other complications were also compared.
47 patients had DVT (27% in the LMWH therapy group and 65% in the pneumatic compression group). Only one case was symptomatic for DVT but there was no pulmonary embolism. Only one patient (LMWH group) had major bleeding.
In patients undergoing TKA, LMWH therapy (given subcutaneously) provides superior thromboprophylaxis to pneumatic compression of the foot.
Elliott CG, Dudney TM, Egger M, et al (Univ of Utah, Salt Lake City)
Calf-Thigh Sequential Pneumatic Compression Compared With Plantar Venous Pneumatic Compression to Prevent Deep-Vein Thrombosis After Non-Lower Extremity Trauma
J Trauma 47: 25-32, 1999
This article compares the effectiveness of calf-thigh sequential pneumatic compression with the plantar venous intermittent pneumatic compression for prevention of thromboembolism (venous) in patients with major trauma.
149 out of 181 patients with severe trauma not involving lower extremities were randomly assigned to either calf-thigh sequential pneumatic compression device or a plantar venous intermittent device. Within 8 days after randomization a bilateral compression US test was used to evaluate the presence of DVT.
62 patients in each group completed the study. DVT occurred in 65% of the calf-thigh sequential compression group versus 21% of the plantar venous intermittent (PVIC) group. Of the 13 patients in the PVIC group who developed DVT, 7 had bilateral involvement. On the other hand in the other group (C-TSC) all 4 cases of DVT were unilateral.
CTSC is more effective than PVIC in preventing DVT after major trauma.
Caprini JA, Arcelus JI, Reyna JJ, et al (Evanston Northwestern Healthcare, III; Northwestern Univ, Chicago; Hospital de la Axarquia, Velez-Malaga, Spain)
Deep Vein Thrombosis Outcome and the Level of Oral Anticoagulation Therapy
J Vasc Surg 30: 805-812, 1999
The effects of oral anticoagulation level on DVT resolution and DVT outcomes are analyzed.
35 limbs of 33 patients with acute symptomatic DVT have been analyzed. Initially all patients received 5 days of IV unfractionated sodium heparin, adjusted to produce an activated thromboplastin time of 2.0-2.5 times higher than baseline. They were then given 6 months of warfarin targeted to an INR of 2.0-3.0. The patients were followed up for DVT resolution by venous duplex scanning and physical examination.
By 1 year DVT had completely resolved in 68% of limbs. At 1, 3, and 6 months’ follow-up, the median INR value was significantly elevated in patients whose DVT resolved. Those with subtherapeutic INR values were significantly more likely to have incomplete resolution of DVT. Those with occlusive thrombi were less likely to have complete DVT resolution.
62% of these limbs developed chronic venous insufficiency compared to 11% of those without occlusion.
To reduce the risk of incomplete thrombotic resolution warfarin therapy should be targeted to achieve an INR of 2.0-3.0.
Gould MK, Dembitzer AD, Sanders GD, et al (Veterans Affairs Palo Alto Health Care System, Calif; Stanford Univ, Calif)
Low-Molecular-Weight Heparins Compared With Unfractionated Heparin for Treatment of Acute Deep Venous Thrombosis: A Cost-Effectiveness Analysis
Ann Intern Med 130: 789-799, 1999
This is a study of the cost-effectiveness of low molecular weight heparins (LMWH) versus unfractionated heparins (UH) for the treatment of DVT.
A meta-analysis of randomized trials was used to assess the likelihood of clinical outcomes. Medicare and other sources were used to gather cost data. The two therapies were compared in terms of cost, quality-adjusted life- years (QALYs) and incremental cost-effectiveness ratios.
The analysis supports the cost effectiveness of LMWH as an inpatient treatment of DVT. Even on an outpatient basis LMWH is a cost saving alternative.
Savage KJ, Wells PS, Schulz V, et al (Univ of Western Ontario, London, Canada; London Health Sciences Ctr; Univ of Ottawa, Ont, Canada)
Outpatient Use of Low Molecular Weight Heparin (Dalteparin) for the Treatment of Deep Vein Thrombosis of the Upper Extremity
Thromb Haemost 82: 1008-1010, 1999
Upper extremity deep vein thrombosis (DVT) is a known cause of morbidity and mortality. A prospective cohort trial of the use of low molecular weight heparin (LMWH) in the outpatient management of upper extremity DVT is reported.
46 patients with objectively documented upper extremity DVT were managed on an outpatient basis with Dalteparin 200 aXa u/kg for a minimum of 5 days. Warfarin was usually begun on the first day with a target INR of 2 to 3. A history of a central line or malignancy was noted in most patients. Follow up was for 12 weeks.
There was no pulmonary embolism. One patient had recurrent DVT during treatment with extension of thrombosis. 7 patients died of underlying disease. One patient experienced major bleeding.
The findings support the safety and effectiveness of Dalteparin in the treatment of upper extremity DVT and is also cost effective.
Gonzalez-Fajardo JA, Arreba E, Castrodeza J, et al (Hosp Clinico Universitario, Valladolid, Spain)
Venographic Comparison of Subcutaneous Low-Molecular Weight Heparin With Oral Anticoagulant Therapy in the Long-term Treatment of Deep Venous Thrombosis
J Vasc Surg 30: 283-292, 1999
The rate of thrombus regression in cases of deep vein thrombosis (DVT) was evaluated by venograms after treatment with a fixed dose of low molecular weight heparin (LMWH) for 3 months and compared with daily oral anticoagulant therapy in an open randomized trial.
Of 165 patients, 85 were randomly assigned to LMWH group (40 mg enoxaparin 12 hourly for 75 days followed by once daily 40 mg dose for 3 months) and 80 were assigned to oral anticoagulant group (initially in the hospital standard unfractioned heparin, followed by warfarin for 3 months).
The extent of venous thrombosis was evaluated by quantitative venography (Marder score – 0 points for no DVT and 40 points for total occlusion of all deep veins).
The rate of thrombus reduction was assessed by the reduction in the Marder score.
Efficacy was defined as the ability to avert symptomatic extension or recurrent venous thromboembolism. Safety was defined as the occurrences of hemorrhage.
The effect of therapy was better in the LMWH group (49.4% vs 24.5% reduction). It also had a lower rate of recurrent venous thromboembolism (95% vs 23.7%).
Patients treated with enoxaparin had better reduction in quantitative venographic scores, lower rate of recurrent thromboembolism and a lower rate of bleeding compared with those on warfarin therapy.
Libertiny G, Hands L (John Radcliffe Hosp, Oxford, England)
Deep Venous Thrombosis in Peripheral Vascular Disease
Br J Surg 86: 907-910, 1999
Peripheral vascular disease is not listed as a risk factor for deep vein thrombosis (DVT). The incidence of thrombosis of deep veins of the lower limb was prospectively investigated by color duplex US before any radiologic or surgical procedure was performed.
136 patients who were admitted for anteriography, angioplasty or arterial reconstruction underwent color duplex sonography (40 controls without PVD were also subjected to color duplex ultra-sonography). Of these 136 cases, 72 had PVD with claudication, 26 had ischemic rest pain, and 38 had gangrene. Age, ankle-brachial pressure index (ABPI) and other risk factors were analyzed.
US changes consistent with DVT were found in significantly more PVD patients than in controls (27 vs 2). ABPI was the most significant risk factor DVT was related to the degree of ischemia.
Kraaijenhagen RA, in ¢t Anker PS, Koopman MMW, et al (Academic Med Ctr, Amsterdam)
High Plasma Concentration of Factor VIIIc Is A Major Risk Factor for Venous Thromboembolism
Thromb Haemost 83: 5-9, 2000
Several inherited thrombophilic defects have been established as risk factors for venous thromboembolism.
This article reviews factor VIIIc as a risk factor for venous thrombosis.
This study included 65 patients with a confirmed single episode of venous thromboembolism (Gr I) and 60 patients with recurrent venous thromboembolism (Gr II).
Also 60 other patients suspected of venous thromboembolism but ruled out by investigations (Gr III). The 3 groups were compared for plasma factor VIIIc levels.
19% of Gr I patients and 33% of Gr II cases had significantly elevated levels of factor VIIIc. The relationship between factor VIIIc and thrombosis was unchanged by adjustment for fibrinogen, C-reactive protein or established thrombophilic risk factors.
Joynt GM, Kew J, Gomersall CD, et al (Chinese Univ of Hong Kong, Shatin)
Deep Venous Thrombosis Caused by Femoral Venous Catheters in Critically III Adult Patients
Chest 117: 178-183, 2000
Central venous catheterization of critically ill patients is an invasive procedure that carries significant risks. Femoral cannulation can avoid some of these risks. The risk of deep venous thrombosis (DVT) associated with femoral venous catheterization has been prospectively evaluated.
140 patients in a mixed surgical – medical ICU underwent femoral venous catheterization during a 2-year period. Data was collected on a wide range of clinical variables. Patients underwent compression and color duplex US examination of both femoral veins before catheterization 12 hours after insertion and thereafter daily till the catheter was in place.
They were followed up 24 hours and 1 week after catheter removal. The incidence of catheter related DVT was analyzed and risk factors assessed.
Of 124 patients evaluated, 14 had DVT (iliofemoral vein) of which only 2 were clinically apparent. 12 were catheter-related and 2 occurred in the opposite (uncatheterized) leg.
DVT was seen as early as the first day after catheterization and as late as 1 week after removal. The risk was unaffected by the number of insertion attempts, the occurrence of arterial puncture or hematoma, the duration of catheterization coagulation variables or medications infused.
There were 3 deaths but there was no suspicion of pulmonary embolism.
Girard P, Musset D, Parent F, et al (Hopital Antoine Beclere, Clamart, France)
High Prevalence of Detectable Deep Venous Thrombosis in Patients With Acute Pulmonary Embolism
Chest 116: 903-908, 1999
The prevalence of detectable residual DVT in cases of acute pulmonary embolism has not been determined. This article evaluates the prevalence of DVT among patients with acute pulmonary embolism (PE) was retrospectively in 228 patients (with angiographically proven PE).
Medical records of all patients of PE were reviewed. All these cases were proved by pulmonary angiography. Bilateral lower limb venography was routinely used for these patients.
DVT was detected in 174 persons (81.7%) of these 128 (60%) were proximal DVT. Only 72 (42%) patients were clinically apparent.
Venography revealed a high rate (82%) of residual DVT in cases of PE.
Ribeiro A, Lindmarker P, Johnsson H, et al (Karolinska Inst, Stockholm)
Pulmonary Embolism: One-Year Follow-up With Echocardiography Doppler and Five-Year Survival Analysis
Circulation 99: 1325-1330, 1999
In pulmonary embolism (PE), there is often pulmonary hypertension and right ventricular overload. This can be correctly diagnosed early with measurement of pulmonary artery systolic pressure (PASP) and right ventricular (RV) function. The course of these 2 parameters was analyzed within a year after the diagnosis of PE.
The study included 78 patients with acute PE who had echocardiography Doppler performed at the time of diagnosis and repeated throughout the next year. The values of PASP were plotted against time in 70 patients.
Five-year survival rates were analyzed and risk factors analyzed for persistent pulmonary hypertension, RV dysfunction, and 5-year mortality.
The PASP decreased exponentially for about a month and then stabilized. During this period RV function improved.
Persistent pulmonary hypertension after 1 year was associated with a PASP of more than 50 mm of Hg at the time of diagnosis of acute PE and an age more than 70 years. High mortality (5-year) was associated most commonly with underlying cancer.
Pulmonary endarterectomy was required in those with persistent pulmonary hypertension.
These findings are valuable in planning the follow-up and care of acute PE patients.
Marston WA, Carlin RE, Passman MA, et al (Univ of North Carolina, Chapel Hill)
Healing Rates and Cost Efficacy of Outpatient Compression Treatment for Leg Ulcers Associated With Venous Insufficiency
J Vasc Surg 30: 491-498, 1999
The authors evaluate the healing rates and cost efficacy of the ambulatory compression techniques of treatment.
This prospective study includes 252 patients who had either clinical or duplex scan evidence of chronic venous insufficiency and active ulceration on one leg.
A detailed history and clinical examination was performed to determine the cause of the ulceration.
Ambulatory compression techniques used included Unna’s paste boot and 3 or 4 layer sustained compression wraps based on the attending physician’s discretion.
Wound measurements were taken at 1-3 week’s interval. Home health nursing visits were used if needed between visits to the clinic.
Cost was based on actual Medicare reimbursements. Risk factors for ulcer healing were factored into the data analysis.
4 layer compression was used in 69%, 3 layer compression in 13% and Unna’s paste boot in 18%. At 10 weeks, 57% ulcers had healed; at 16 weeks, 75% had healed; and at 1 year 96% had healed, with 1 major amputation necessary.
The average cost at 10 weeks was $ 1444- $ 2711 (physician reimbursement 48%, laboratory testing 19%, and dressing materials 33%.
Compression treatment is a reliable, cost effective form of treatment for venous ulcers. Adjuvant treatment may be effective but is not cost effective.
Buhs CL, Bendick PJ, Glover JL (William Beaumont Hosp, Royal Oak, Mich)
The Effect of Graded Compression Elastic Stockings on the Lower Leg Venous System During Daily Activity
J Vasc Surg 30: 830-835, 1999
Gradient ambulatory compression therapy is the mainstay of treatment for chronic venous insufficiency though the mechanism of its effects is unclear.
The effects of graded elastic compression stockings on the venous system of the lower leg in healthy individuals were evaluated.
21 healthy women (mean age 29 years) (clinical class 0 on physical examination) were studied on 2 working days (once while wearing the stockings and once without).
At the beginning of each day and after about 4 ½ hours of normal activity, duplex US scanning was done to measure the diameter of the posterior tibial and peroneal and the long saphenous veins at midcalf level. Also calf circumference and the number and caliber of medial calf perforating veins was assessed.
During the work day the calf circumference increased by an average 5 mm (with stockings). The number of medial calf perforating veins increased by 1.8 (without stockings) and by 0.4 (with stockings).
Compression stocking help to preserve venous caliber in the deep superficial and perforating venous systems of the lower leg. This effect may explain the benefit of compression therapy for venous insufficiency.
Margolis DJ, Berlin JA, Strom BL (Univ of Pennsylvania, Philadelphia)
Risk Factors Associated With the Failure of a Venous Leg Ulcer to Heal
Arch Dermatol 135: 920-926, 1999
This is a retrospective study to determine the risk factors associated with failure of a venous leg ulcer to heal after compression therapy for 24 weeks.
The study includes 260 consecutive patients treated at an outpatient clinic. The effect of each risk factor was assessed by single and multiple variable logistic regression analysis.
35% of ulcers did not heal in 24 weeks. Failure to heal was associated with wound area (odds ratio [OR] 1.19), increased wound duration (OR 1.09) decreased ankle brachial index (OR 9.25), more limb ulcers (OR 1.19), non white ethnicity (OR 1.88), history of venous stripping or ligation (OR 4.58) inability to walk 1 block (OR 1.59), undermined wound margin (OR 0.92), fibrin covered wound (OR 3.42), pressure of lipodermatosclerosis (OR 0.80) and a history of surgical wound debridement (OR 1.90).
The authors have listed ten factors for failure of leg ulcers to heal in 24 weeks.
Padberg FT Jr, Maniker AH, Carmel G, et al (University of Medicine and Dentistry of New Jersey, Newark; VA New Jersey Health Care System, East Orange)
Sensory Impairment: A Feature of Chronic Venous Insufficiency
J Vasc Surg 30: 836-843, 1999
The presence extent and distribution of sensory neuropathy among patients with (CV1) chronic venous insufficiency have been evaluated.
23 limbs of 14 men with CV1 were studied. Those with diabetes mellitus, previous surgery on the studied limb or other diseases associated with neuropathy were excluded.
11 limbs with mild disease (CEAP-clinical, etiologic, anatomic, and pathologic classification – class 2) were compared with 12 limbs with severe disease (CEAP class 5) in terms of sensory thresholds at foot, ankle, calf, thigh and palm (measured by Semmes-Weinstein filaments method) were compared with the findings of a complete clinical assessment by an experienced neurosurgeon. Duplex US, and an plethysmogragy were performed to assess venous reflux.
There was significant difference in the two groups, just proximal to the medial malleolus (usual site of venous ulcers). The sensory changes were related to the degree of trophic changes but not to any specific dermatomal or cutaneous nerve distribution. Vibration sense and deep tendon reflexes were also significantly reduced (severe CV1).
Limb with venous hypertension have local neurological injury at the same site as the maximal skin changes.
Libertiny G, Hands L (John Radcliffe Hosp, Oxford, England)
Lower Limb Deep Venous Flow in Patients With Peripheral Vascular Disease
J Vasc Surg 29: 1065-1070, 1999
The effects of PVD on deep venous blood flow in the lower limbs was evaluated by color duplex US scanning.
The study includes 89 patients with symptomatic chronic PVD and 35 age-matched controls. Color duplex US scanning was performed on all to determine popliteal vein diameter and flow velocity, which were compared with the ankle-brachial index.
23 were further studied during reactive hyperemia with repeat measurements after an ankle cuff was used to prevent venous return from the foot.
Ankle brachial pressure index co-related with popliteal vein diameter but negatively correlated with venous flow velocity in the PVD group. In the PVD group, reactive hyperemia was associated with additional reductions in popliteal vein diameter. In contrast, the diameter increased in controls.
In response to blocking venous return from the foot, the PVD group showed an increase in popliteal vein diameter at rest and elimination of hyperemia-induced reduction in diameter.
Even though, the popliteal vein decreased in diameter during reactive hyperemia, patients in the PVD had a lesser increase in flow velocity than controls.
This phenomenon (viz. decrease in size of popliteal vein) in response to chronic ischemia seems to be an active process related to washout of humoral factors from the distal ischemic tissues thus leading to increased flow velocity (may have a protective effect against deep vein thrombosis).
Heron E, Lozinguez O, Emmerich J, et al (Hopital Broussais, Paris; Hopital Saint-Joseph, Paris)
Long-term Sequelae of Spontaneous Axillary-Subclavin Venous Thrombosis
Ann Intern Med 131: 510-513, 1999
There is little data available on the rate and consequences of post-thrombotic sequelae of spontaneous axillary-subclavin venous thrombosis. This is a cross-sectional study to assess these sequelae.
54 patients were included in this study (over a period of 18 years). They were generally treated with anticoagulants. No thrombolytic therapy was given. The severity of symptoms were graded on a scale of 0-10, as well as on a 6 point verbal rating scale.
US sequelae were graded as 0, normal flow; 1, moderate obstruction, and 2 severe obstruction.
13% complained of severe or intolerable pain, 47% reported no or negligible pain. 78% had pain scores of 0-3, 9% had scores of 7-10. The US sequelae were graded as 2 in 22% but were unrelated to the symptom severity scores.
Spontaneous axillary-subclavin venous thrombosis has a good clinical outcome. The severity of symptoms does not relate to the US scores. Only 10% had severe residual symptoms – therefore anticoagulants remain the frontline treatment.
Bower TC, Nagorney DM, Cherry KJ Jr, et al (Mayo Clinic and Mayo Found, Rochester, Minn)
Replacement of the Inferior Vena Cava for Malignancy: An Update
J Vasc Surg 31: 270-281, 2000
A retrospective study of aggressive surgical management of IVC tumors based on patient selection, operative technique, and early and late outcomes.
29 patients (11 males ages 16-88 years) who underwent IVC replacement for removal of primary (n=2) or secondary (n=27) tumors have been studied from the following view points: patients condition, type and location of tumor segment of IVC replaced, graft patency, pre and postoperative performance status, tumor recurrence and survival. The follow up was for an average of 2.8 years.
10 had infrarenal IVC replacement, 13 had suprarenal IVC replacement with liver resection and retro hepatic cava replacement and 3 patients had both infra and suprarenal IVC replacement. A large diameter (14-20 mm) PTFE graft was used in 28 patients. One patient had a superficial femoral vein graft.
There were 2 (6.9%) early deaths (1 from DIC and the other from MSOF). 16 patients (55.2%) had no complications. The other 12 had complications like cardiopulmonary problems (5), bleeding (5), chylous ascites or large pleural effusions (2 each) and bile leak, bilateral lower extremity edema and tibial vein thrombosis (1 each).
Graft occlusion occurred in 3 patients (4 months to 6.3 years postoperatively). 26 cases had good to excellent initial postoperative performance. 11% died of tumor recurrence.
Aggressive surgical management in carefully selected patients with primary or secondary IVC cancers can be accomplished safely with few complications.
M. van ‘t Riet, J. W. A. Burger, J. M. van Muiswinkel, G. Kazemier, M. R. Schipperus and H. J. Bonjer (Departments of Surgery, Radiology and Haematology, Erasmus University Medical Centre, Rotterdam, The Netherlands)
Diagnosis and Treatment of Portal Vein Thrombosis Following Splenectomy
BJS September 2000 Vol. 87 (9), Pg. 1229-1233
Portal vein thrombosis is a rare but potentially fatal complication of splenectomy. The incidence of portal vein thrombosis appears low, but is probably underestimated because symptoms, such as abdominal pain and fever, are non-specific and portal vein thrombosis can easily develop without any symptoms.
Identification of patients with portal vein thrombosis is crucial to allow early treatment and prevent potentially fatal complications such as bowel infarction or later portal hypertension.
No patient with a lymphoproliferative disorder, iatrogenic splenectomy, traumatic lesion or idiopathic thrombocytopenia had portal vein thrombosis. Statistical analysis with Fisher’s exact test showed that both haemolytic anaemia (P=0.005) and myeloproliferative disorder (P=0.03) were significant risk factors for developing portal vein thrombosis after splenectomy.
Preoperative prophylactic anticoagulant therapy with low molecular weight subcutaneous heparin was administered.
Por tal vein thrombosis was not suspected initially in any patient. When abdominal pain, fever or leucocytosis developed, ultrasonography of the abdomen was performed to look for an abscess.
After diagnosis of portal vein thrombosis, prompt therapy was initiated with intravenous heparin combined with warfarin or with alteplase (human recombinant tissue plasminogen activator; tPA) directly into the portal vein thrombus through a transhepatic catheter, placed percutaneously or with systemic streptokinase or with warfarin alone or with prophylactic antithrombotic therapy with daily subcutaneous injections of 7500 units nadroparin was continued as monotherapy for 1 month after the portal vein thrombosis was diagnosed.
Patients with portal vein thrombosis who were treated within 10 days after splenectomy, the thrombus in the portal vein resolved on duplex ultrasonography.
All portal veins remained patent in the patients who responded to treatment. Patients studied by duplex scanning in whom the interval between splenectomy and initiation of therapy was 10 days or longer, no effect on the thrombus was seen and extensive collateral flow developed.
Subcutaneous bleeding in a laparotomy wound that was ligated under local anaesthesia. Recurrent nose bleeds for several days after operation.
None of the patients in this study developed the fatal complication of bowel necrosis as a result of portal vein thrombosis.
Portal vein thrombosis is a dreaded complication of splenectomy. Hypercoagulability after splenectomy and stasis of blood in the stump of the splenic vein appear to predispose to portal vein thrombosis.
Splenectomy is followed by increased viscosity due to high platelet and leucocyte counts as a result of absent splenic breakdown. Another sequel of splenectomy is increased rigidity of erythrocytes possibly caused by the accumulation of nuclear remnants (e.g. Howell-Jolly bodies); the greater rigidity contributes to a higher plasma viscosity.
Stasis of blood in the stump of the splenic vein may be a mechanical risk factor for thrombosis of the portal vein. There is a correlation between the size of the spleen and the diameter of the splenic vein; therefore, splenomegaly possibly increases the risk of portal vein thrombosis.
In studies that reported visceral gangrene, patients did not receive preoperative thrombus prophylaxis. Possibly, this played a role in preventing visceral gangrene.
The incidence of asymptomatic portal vein thrombosis seems to be significantly higher than that of symptomatic thrombosis.
Prompt initiation of therapy for portal vein thrombosis seems to be an important determinant for success.
The role of prophylactic heparin remains uncertain. It is possible that increasing the dosage of prophylactic heparin might be beneficial.
In conclusion, portal vein thrombosis should be suspected in patients with either fever or abdominal pain after splenectomy. Early treatment is more likely to restore normal flow in the portal vein and to prevent portal hypertension. Routine Doppler ultrasonography after splenectomy might enable early diagnosis and effective treatment.
Visceral Renal Artery Disease
Schneider DB, Nelken NA, Messina LM, et al (Univ of California, San Francisco)
Isolated Inferior Mesenteric Artery Revascularization for Chronic Visceral Ischemia
J Vasc Surg 30: 51-58, 1999
A series of patients with isolated revascularization of the inferior mesenteric artery (IMA) have been reported.
11 cases with chronic visceral ischemia have been studied. 8 of these underwent isolated IMA revascularization and 3 were functionally left with an isolated IMA revascularization because of failure of concomitant coehae and SMA repairs.
All patients were symptomatic and underwent arteriography. 4 patients had bypass grafting, 4 had transaortic endarterectomy. 2 had reimplantation and 1 had patch angioplasty. The median follow up was 6 years.
One patient died perioperatively. The remaining 10 had cures or improvement at discharge. One case had a thrombosis but was reoperated successfully. 2 patients had recurrent symptoms despite patent IMA repairs but were successfully revascularized (interrupted collateral circulation due to previous bowel resection may have been responsible in both these cases).
An objective follow up (arteriography after 8 months to 1 year) demonstrated patency.
The authors conclude that when revascularization of other major visceral vessels is not possible, but there is an intact IMA collateral circulation, this procedure is very useful for chronic visceral ischemia.
Mateo RB, O’Hara PJ, Hertzer NR, et al (Cleveland Clinic Found, Ohio)
Elective Surgical Treatment of Symptomatic Chronic Mesenteric Occlusive Disease: Early Results and Late Outcomes
J Vasc Surg 29: 821-832, 1999
Surgical treatment of the rare symptomatic chronic mesenteric occlusive disease (SCMOD) has been a challenge to the surgeon. This study evaluates the postoperative mortality and morbidity rates, recurrence rates and factors responsible for the outcomes.
85 consecutive patients were followed up for a median of 3.1 years (aged between 27-89 years). Symptoms included abdominal pain (92%) weight loss (87%) or both; diarrhoea (44%) and anorexia (33%).
All patients had occlusion of SMA, 80% had coehac axis involvement and 69% had IMA involvement. 58% had involvement of all 3 vessels and also had occlusive aortic disease.
Complete revascularization was done in 25% of cases. The techniques used were retrograde bypass grafting, antigrade bypass grafting, transaortic endarterectomy, transarterial endarterectomy, arterial thrombectomy and arterial re-implantation.
There were 5 early and 2 late deaths (8%) 78 patients were discharged symptom free. 31 of these died of postoperative complications. Overall 76% were symptom free at 3 years follow up. The factors responsible for the mortality were older age, hypertension, cardiac disease and other vessel disease.
Concomitant aortic replacement, renal disease and complete revascularization showed greater morbidity. The choice of graft material was associated with recurrence of symptoms and survival.
The 5 and 10 year survival rates after elective SCMOD surgery are 64% and 36% respectively.
Yilmaz EN, Vahl AC, van Rij G, et al (Academic Hosp Vrije Universiteit, Amsterdam; Kennemer Gasthuis, Harrlem, The Netherlands)
Endoluminal Pulse Oximetry of the Sigmoid Colon and the Monitoring of the Colonic Circulation
Cardiovasc Surg 7: 704-709, 1999
A pulse oximetry technique for early detection of colonic ischemia has been described.
The study includes 90 patients (over 7 years) at risk of colonic ischemia after a ruptured aortic aneurysm and its repair. Endoluminal pulse oximetry was performed to monitor mucosal oxygen saturation during the surgery. Colonoscopy was performed on all cases.
In all 30 cases of colonic ischemia were detected (26 by endoscopy and 4 at repeat laparotomy). Pulse oximetry showed absence of pulsatile signal in 33 cases. It had a sensitivity of 100% and specificity of 95% with 3 false positives.
This is a promising non invasive tool for early detection of colonic ischemia.
Delaney CP, O’Neill S, Manning F, et al (Univ College Dublin; Biotrin Internatl, Dublin)
Plasma Concentrations of Glutathione S-Transferase Isoenzyme Are Raised in Patients With Intestinal Ischaemia
Br J Surg 86: 1349-1353, 1999
Patients with acute mesenteric ischemia have a high mortality, unless they are diagnosed early.
The clinical picture is often non specific and there is no reliable laboratory test. The aGST is specific to the liver and the small intestine.
This article assesses the capability of plasma aGST to help predict the presence of acute mesenteric ischemia. 26 patients, clinically suspected to have acute mesenteric ischemia were investigated.
Besides other routine tests plasma was frozen for later measurement of aGST. The presence of ischemia was confirmed by surgery or autopsy.
The diagnosis of acute mesenteric ischemia was made in 12 patients. All these cases had a significantly high level of aGST than the other patients. Other biochemical values including pH also differed significantly between groups.
However aGST was the only accurate predictor of acute mesenteric ischemia (cut off point of 4 mg/ml). It had a sensitivity of 100% with a specificity of 86%. aGST is a reliable parameter for diagnosing acute mesenteric ischemia.
Van Rooden CJ, van Bockel JH, De Backer GG, et al (Univ Hosp Leiden, The Netherlands; Univ Hosp Gent, Belgium)
Long-term Outcome of Surgical Revascularization in Ischemic Nephropathy: Normalization of Average Decline in Renal Function
J Vasc Surg 29: 1037-1049, 1999
Renal ischemic can cause progressive fibrosis in the nephrons. There is a need for data on whether revascularization procedures can permit recovery of renal function. The long term renal function results of revascularization for ischemic nephropathy are reviewed.
61 patients of ischemic nephropathy undergoing surgical revascularization have been evaluated. The Cockcroft and Gault formula was used to assess the patients long term course of decline in estimated glomerular filtration rate (EGFR) before surgery.
8 months postoperatively and at an average of 47 months postoperatively. These slopes were matched with normals (age and sex matched).
The surgical mortality was 13%. Postoperatively 5 patients became dependent on dialysis and another 2 were able to come off dialysis. The mean EGFR increased significantly. The estimated rate of decline in EGFR decreased. By comparison the rate of decline in the controls was higher. Renal function also improved.
Surgical revascularization for renal ischemia leads to restoration of renal function in most patients.
Wong JM, Hansen KJ, Oskin TC, et al (Wake Forest Univ, Winston-Salem, NC)
Surgery After Failed Percutaneous Renal Artery Angioplasty
J Vasc Surg 30: 468-483, 1999
Percutaneous transluminal renal artery angioplasty (PTRA) is a safe and effective procedure for renovascular disease. However, failure of PTRA (F-PTRA) requires surgical intervention for relief of the hypertension or renal insufficiency.
51 such cases (surgical intervention after F-PTRA) have been analyzed retrospectively.
These 51 patients (32 with atherosclerosis and 19 with fibromuscular dysplasia FMD) had renovascular disease after F-PTRA. Repair procedures were done to address hypertension, ischemic nephropathy, acute renal artery thrombosis, renal artery rupture and infected pseudo aneurysm.
The results were compared with those of 487 patients (481 artherosclerosis and 46 FMD) who were also treated surgically. The variables studied were operative management, blood pressure and renal function.
Operative management after F-PTRA resulted in 3% mortality, and required emergency repair or nephrectomy in 16% of patients. 50% of atherosclerotic and 65% of FMD patients required more complex operations.
The main improvement was seen in blood pressure levels and renal function values. The estimated glomerular filtration rate was significantly increased.
Cambria RP, Kaufman JL, Brewster DC, et al (Harvard Med School, Boston)
Surgical Renal Artery Reconstruction Without Contrast Arteriography: The Role of Clinical Profiling and Magnetic Resonance Angiography
J Vasc Surg 29: 1012-1021, 1999
Contrast angiography is considered the gold standard for diagnosis and treatment of atherosclerotic renovascular disease (RVD). The impact of a selective policy of selective renal artery reconstruction (RAR) with MR angiography (MRA) as the only preoperative imaging study is reported.
25 patients clinically diagnosed as RVD, had RAR performed with MRA (gadolinum enhanced) as the only preoperative imaging study. The initial assessment showed poorly controlled hypertension, hypertensive crisis, acute pulmonary oedema and deteriorating renal function.
At surgery, significant RVD in the main renal artery was seen in 37 of 38 explored arteries. MRA missed one accessory renal artery. 21 patients had comprehensive RAR (hepatorenal artery bypass graft, combined aortic and RAR, transaortic endarterectomy and aortorenal bypass graft).
Both hypertension and renal function improved. There were no deaths. For selected patients MRA before RAR is an acceptable imaging modality.
Lee PC, Rhee RY, Gordon RY, et al (Univ of Pittsburgh, Pa)
Management of Splenic Artery Aneurysms: The Significance of Portal and Essential Hypertension
J Am Coll Surg 189: 483-490, 1999
Splenic artery aneurysms (SAA) are rare. They are seen in portal hypertension (PHTN) particularly in those undergoing orthotopic liver transplantation (OLT). A retrospective study to review the risk of SAA rupture and its management.
Medical records and radiographs of all patients (34) who underwent surgery for SAA (February 87 – June 88) were reviewed for clinical features and management, risk factors and patient outcome. Patients were divided with 2 groups – ruptured and elective presentations.
62% of the cases were females and the average age 50.6 years. In 12 patients without PHTN, essential hypertension was a significant risk factor. Splenectomy with either resection of SAA or ligation of splenic artery or ligation of SAA and vascular reconstruction were performed.
The mortality was 40% after SAA rupture as against 0% in elective surgery. The mortality was higher in those cases who had PHTN. At a mean follow up of 46 months, survival in ruptured SAA was 60% compared with 84% after elective repair.
20 of 22 patients with PHTN underwent OLT. 4 patients underwent SAA repair along with OLT. For 7 patients with ruptured SAA after OLT, the mortality was 57%.
Essential hypertension and PHTN are significant risk factors for development of SAA. Rupture of SAA has significant mortality particularly those with PHTN.
Arca MJ, Gagner M, Heniford BT, et al (The Cleveland Clinic Found, Ohio; Mount Sinai Med Ctr, New York)
Splenic Artery Aneurysms: Methods of Laparoscopic Repair
J Vasc Surg 30: 184-188, 1999
The early experience with laparoscopic approach to treatment of SAA has been reported.
Medical records of 4 patients who underwent laparoscopic repair of SAA were reviewed. There were 3 women and 1 man aged 37-63 years. The mean SAA size was 3.2 cm. 3 cases had a resection of the aneurysm while 1 had simple ligation.
In 3 patients intraoperative ultrasound scanning with Doppler was used to localise the aneurysm and the feeding vessels. The average time for surgery was 150 min and estimated blood loss 105 ml.
No intraoperative complications occurred. The mean hospital stay was 2.2 days. This approach is safe and effective and permits a short hospital stay with favorable outcomes.