Speciality
Spotlight

   




   


Surgery


   

 















Cardiac
Surgery

  

  • Gundry
    SR, Romano MA, Shattuck OH, et al [ Loma Linda Univ,
    Calif.]

    Seven
    Year follow-up of Coronary Artery Bypasses Performed
    with and Without Cardiopulmonary Bypass

    J
    Thorac Cardiovasc Surg 115: 1273-1278, 1998

         

    To
    decrease the morbidity and hospitalization associated
    with coronary artery bypass grafting [CABG] by
    cardiopulmonary bypass [CPB], surgeons revascularize
    the beating heart [BH] without CPB. Patients treated
    by the same surgeons, by both the techniques, were
    compared and long-term survival and intervention-free
    outcomes were assessed.

     

    Between
    June 1989 and July 1990, 112 patients had CABG with
    CPB and 107 patients had CABG on the beating heart [CABG
    on BH], at the hands of three surgeons. The average
    age and risk factors were identical for the two
    groups. Patients
    undergoing CABG with CPB had an average of 3.2 grafts
    vs 2.4 grafts in the other group.

     

    At
    a seven year follow-up 79% of the former group and 80%
    of the latter group were alive. 
    Cardiac deaths occurred in 9% in the former
    group vs 12% of the latter. However, 16% of patients
    who had CABG with CPB, required catheterization for
    their symptoms as against 30% of patients who had CABG
    on BH. Angioplasty or secondary CABG was required in
    7% of the former as against 20% of the latter group.

     

    Thus
    patients with CABG on BH had twice as many requiring
    repeat investigations and thrice as many interventions
    as compared to the patients who had CABG under 
    CPB.

      

  • Pick
    AW, Orszulak TA, Anderson BJ, et al [Mayo Clinic,
    Rochester, Minn]

    Single
    Versus Bilateral Internal Mammary Artery Grafts :
    10-Year Out-come Analysis

    Ann
    Thorac Surg 64: 599-605, 1997



    The use of the left internal mammary artery [IMA] to
    bypass the left anterior descending coronary artery
    has been associated with superior graft patency,
    reduced cardiac events and enhanced survival, so some
    surgical groups have begun using both IMAs for
    revascularization. To
    determine whether use of both IMAs confers further
    advantage to patients at bypass surgery, a group of
    patients with bilateral IMA [BIMA] bypass procedures
    was compared to a group of single IMA [SIMA] bypass
    procedures. Beginning in January 1984 and continuing
    for 24 months, 160 patients with multivessel disease
    had coronary revascularization procedures with BIMA
    grafts plus saphenous venous grafts, and 160 patients
    had saphenous grafts alone.
    During an extended time to May 1986, a matched
    group of 161 patients with a
    SIMA grafts plus supplementary saphenous venous
    grafts, operated on by the same surgeon were
    identified. The
    three groups of patients were matched for gender,
    preoperative angina, priority status, extent of
    coronary artery disease, left ventricular function,
    and number of distal anastomoses. Diabetes was more
    common in the SIMA group. 
    Operative mortality was 0.6% for the SIMA group
    and nil for the BIMA group.

      

    The average follow-up of 10 years, revealed lower late
    cardiac mortality in the BIMA group; survivals at 10
    years were 75% for the SIMA group vs 85% for the BIMA
    group. Diabetes, age, and lower ejection fractions
    were the main factors responsible for late cardiac
    deaths in all the patients.

      

    Bilateral
    internal artery grafts were associated with reduced
    risk of angina recurrence, late myocardial infarction,
    and other late cardiac events after revascularization.
    Larger studies are suggested to confirm the
    findings.




  • Tatoulis
    J, Buxton BF, Fuller JA [Univ of Melbourne, Australia]

    Results
    of 1454 Free Right Internal Thoracic Artery

    To

    – Coronary
    Artery Grafts

    The
    patients had an average age of 59.
    Eight percent had non-insulin-dependent
    diabetes and 0.5% had insulin-dependent diabetes.
    Decreased left ventricular ejection fraction was
    present in 12%, and unstable angina in 9.9%. In eleven
    patients, FRITA was the only graft.
    There was an average of 3.3 distal anastomoses
    per patient. Bypass time was about 69 minutes and
    aortic clamp time about 49 minutes.

         

    Operative
    mortality was 0.9%, stroke occurred in 1%; and
    myocardiac infarct in 1.3% of the patients. Complications included sternal infection in 1.2%, and reoperation
    for hemorrhage in 1.6%. Survival at 5 years was 96%
    and at 7 years 94%. In
    71 patients followed up for an average of 42 months,
    FRITA was widely patent in 67, displayed a string sign
    in 3, and occlusion in 1.
    The
    right internal thoracic artery can be safely and
    successfully used as a free graft for myocardial
    revascularization. Short and long term results were
    similar to those of single thoracic artery grafting.

          

  • Mohammad Bashar Izzat Loay S. Kabbani, Gianni D. Angelni

    Minimal-access and Minimally invasive Cardiac Surgery

    Recent Advances in Surgery-23, Year-2000

          

    Median sternotomy has remained the standard approach for most open-heart procedures because it provides easy exposure of the entire heart and allows for the various cardiopulmonary by pass and myocardial protection techniques. 

         

    It is fitting at the beginning to define ‘minimally-invasive’ and ‘minimal access” surgical techniques.

        

    Minimizing the ‘invasiveness’ of surgery implies reducing the peri-operative morbidity defined by measures of clinical outcome in comparison to conventional techniques. 

          

    Extracorporeal circulation is another significant cause of patient morbidity. Hence avoiding the use of cardiopulmonary bypass, regardless of the type of surgical incision, is another minimally invasive approach in cardiac surgery.

          

    Currently employed minimal-access approaches to heart operations can be broadly classified into: [I] direct-vision techniques through limited incisions; and [ii] video-assisted approaches using endoscopic methods.

          

    At present, the partial stenotomy incision is the most commonly used minimal-access approach for intra-cardiac operations.

          

    It has many of the advantages of median sternotomy, the incision is easily opened and closed, provides excellent access, allows for standard cardiopulmonary bypass techniques and can be easily converted to full sternotomy in troublesome techniques and can be easily converted full sternotomy in troublesome cases.

          

    With a upper partial sternotomy, the sternum is split from the sternal notch to the level of the third intercostal space.

           

    Alternatively, a lower partial sternotomy incision can be used, dividing the sternum from the xiphoid process up the level of the second rib, and terminating the sternal split into the left 2nd intercostal space.

           

    Minimizing access has been advantageous in clinical experience. For the surgeon, opening and closing the chest is easier and faster, and mediastinal blood loss is significantly reduced.

          

    These patients resume normal activities earlier than those who undergo the conventional operation.

           

    Postoperative pain is also reported to be reduced, both in hospital and after discharge.

           

    Another potential advantage of the minimal access approach is that the pericardium is not fully opened; hence re-operation should be easier and safer.

           

    The potential disadvantages of these procedures should be considered as well.

           

    Paradoxical motion of the chest wall, particularly during coughing, has been observed in most patients.

           

    Video-assistance remains limited to a few applications in cardiac surgery due to the complexities of cardiac procedures.

          

    The only established role for the video-assisted technique at present is in thoracoscopic mitral valve surgery, but it can also be used for harvesting the internal mammary artery in preparation for the minimally invasive direct coronary artery bypass [MIDCAB] procedure.

          

    Coronary artery bypass grafting without cardiopulmonary bypass is a surgical strategy that has gained increasing popularity.

          

    Patients poorly tolerate the side effects of hypotensive non-pulsatile extracorporeal perfusion and systemic cooling.

          

    Early experience with coronary revascularization without cardiopulmonary bypass has been very encouraging, and is now the technique of choice for routine coronary grafting.

          

    The concepts of minimal-access and minimally invasive heart surgery advantageous and deserve further investigation and development.

        

  • Robicsek
    F., Cook JW, Rizzoni W [Carolina Med Ctr, Charlotte,
    NC]

    Sternoplasty for Incomplete Sternum Separation

    J
    Thorac Cardiovasc Surg 116: 361-362, 1998


         

    The
    authors have previously reported a technique for
    surgical repair of poststernotomy separation. In the
    sternum weaving technique, persistent bilateral
    double-row sutures are placed, and transverse
    sutures are used to reunite the sternum halves,
    buttressed by the double axial suture lines. This
    technique is highly useful for patients with
    separation along the complete length of the
    sternum,but some patients have separation only of
    the lower portion of the sternum.
    In these cases the full sternum may sometimes
    be divided just to reapproximate the lower portion.
    A modified technique for reapproximation of
    the separated lower portion of the sternum has been
    described.

     

    This
    modified sternoplasty technique can be used in cases
    of partial postoperative sternum separation.
    This approach was successful in several
    patients with chronic, noninfected partial sternum
    separations. All
    patients showed good results, with early discharge
    from the hospital.

         

  • Fang WC, Helm RE, Kreiger
    KH, et al [Univ. of Massachusetts, Worcester, Cornell
    Univ, New York; North Shore Univ. Hosp., Manhasset, NY]

    Impact of Minimum Hematocrit During Cardiopulmonary Bypass on Mortality in Patients Undergoing Coronary Artery Surgery

    Circulation 96 [suppl II] : II-194-II-199, 1997

         

    Over the years variety of measures have been used to reduce the need for blood transfusion during coronary artery bypass grafting
    [CABG]. The hematocrit commonly falls to a low level in patients undergoing cardiopulmonary bypass
    [CPB] and there is a debate over the minimum safe hematocrit level during this procedure. The mortality effect of the minimum hematocrit level achieved during CPB was investigated.

         

    The analysis included 1638 sequential patients undergoing CABG over 42 months. Patients requiring valve replacement or other concurrent surgical procedures were excluded.

          

    Minimum hematocrit levels reached during PCB was analyzed, along with 31 preoperative risk factors for effect on postoperative mortality.

          

    The initial multiple logistic regression model identified 8 preoperative risk factors as independent predictors of postoperative mortality: shock, renal failure, ventricular arrhythmia, previous open heart surgery, IV nitroglycerine administration, congestive heart failure, aortoiliac disease, and older age. In a further model, minimum hematocrit during CPB was independently associated with mortality risk.

           

    With adjustment for other factors, patients with minimum hematocrit of 14% or below had an increased probability of risk-adjusted mortality With high risk patients, minimum hematocrit of 17% or lower had significantly higher risk of postoperative mortality.

           

    Thus extent to which hematocrit falls during CPB is an independent risk factor for postoperative mortality.

         

  • Johnson D, Perrault H, Vobecky
    SJ, et al [ Ste-Justine Hospital, Montreal; McGill
    Univ, Montreal]

    Influence of the Postoperative Period and Surgical Procedure on Ambulatory Blood Pressure -Determination of Hypertension Load After Successful Surgical Repair of Coarctation of the Aorta 

    Eur Heart J 19: 638-646, 1998

         

    The monitoring of blood pressure after surgical correction of coarctation of the aorta is usually performed using a sphygmomanometer. Ten to 40% of patients who undergo an apparently successful repair of coarctation of aorta have hypertension 10 to 20 years later. The hypertension load was quantified using 24-hour ambulatory blood pressure monitoring in patients less than 10 years and more than 10 years after surgery. The type of surgical repair was also assessed.

        

    Ambulatory blood pressure recordings were taken using an Accutracker II monitor every 30 minutes in the daytime and every one hour at night. Patients were grouped in two groups according to the period elapsed after surgery. Group 1 less than 10 years and Group 2 more than 10 years after surgery. A group of healthy adolescents were used as a control group. Of the twenty-one patients 12 had end-to-end anastomosis and 9 left subclavian artery angioplasty for correction of the
    coarctation.

        

    Compared with the controls all operated cases showed higher day and night systolic and diastolic blood pressures. Daytime systolic hypertension occurred in 20% in Group 1 and in 49% in Group 2. There was no diastolic hypertension. There were also no differences in blood pressure recordings in the two types of operation.

        

    Patients undergoing repair for coarctation of aorta develop hypertension with time and need constant monitoring.

          

  • Shaffer KM, Mullins CE, Grifka
    RG, et al [ Baylor College of Medicine, Houston; Texas Children’s Hospital, Houston]

    Intravascular Stents in Congenital Heart Disease: Short and Long-Term Results From a Large Single-Center Experience

    J Am Coll Cardiol 31: 661-667, 1998



    Intravascular stents for the treatment of patients with congenital heart disease and vascular stenoses were evaluated by Food and Drug Administration [FDA] phase 1 and 2 clinical trials at Texas Children’s Hospital. Results of only FDA-approved investigational device exemption study of balloon-expandable stents in patients with congenital heart disease and vascular stenoses were reported.



    All patients enrolled in the study had stenoses requiring treatment. Stents were placed in 3 groups of patients: those with postoperative pulmonary artery [PA]
    stenoses, congenital PA stenoses, and stenoses of systemic veins/venous
    anastomoses. A total of 347 stents were placed in 200 patients between September 1989 and June 1995. The Palmaz stent was used in all cases. Median patient age at implantation was 10.5 years. Data were collected before and after stent implantation and at follow-up.



    All three groups showed marked fall in gradients across the
    stenoses, and marked increase in vessel diameters. Right ventricular pressure decreased in both congenital as well as postoperative pulmonary
    stenoses, and perfusion to the lungs increased considerably. The changes were seen steady at follow-up catheterization done at a mean of 14 months after implantation. There were 4 cases of stent migration in the earlier cases and three patients had
    restenosis. Two deaths were directly attributed to stent implantation.



    Intravascular stents proved to be safe and effective in the management of PA stenoses and other vascular
    anastomoses; there is no long-term morbidity and the favourable results appear immediately and continue into follow-up.

        

  • Daniels CJ, Cassidy SC, Teske
    DW, et al [ Columbus Children’s Hospital and Ohio State
    Univ, Columbus]

    Reopening After Successful Coil Occlusion for Patent ductus Arteriorus

    J Am Coll Cardiol 31: 444-450, 1998

      

    A study of children who had undergone successful coil occlusion of patent ductus arteriorus [PDA] was conducted to determine the frequency of reopening and the factors that may predict reopening.

       

    The patients underwent percutaneous transarterial PDA coil occlusion. The length and diameter of PDAs were determined.Doppler echocardiography was performed within 24 hours of coil occlusion to document success. Patients were reevaluated at 12 months.

       

    Coil occlusion was performed in 22 children with a median age of 4.9 years. Clinical success with loss of continuous murmur was achieved in 91% and in 90% doppler echocardiography was negative for PDA shunting. Five patients [22%] were seen to have reopening at follow-up. These patients had larger minimal diameter of 1.4 mm vs 1.2 mm and shorter PDA length 2.9 mm vs 7.1 mm.
    A ngiographic appearance in 3 of these patients showed type B PDA [conical with short ductal
    ampulla].

       

    Thus despite successful coil occlusion for PDA, reopening is common. Previous reports have indicated that success is associated with minimal diameter of the PDA. In particular failure may occur with a wide-diameter and short length PDA. Angiographic type B PDA is also associated with reopening. 

         

  • PreitoLR, DeCamillo DM, Konrad DJ, et al [ Cleveland Clinic Found, Ohio]

    Comparison of Cost and Clinical Outcome Between Transcatheter Coil Occlusion and Surgical Closure of Isolated Patent Ductus Arteriorus

    Pediatrics 101: 1020-1024, 1998

        

    Transcatheter closure of patent ductus arteriorus [PDA] using Gianturco coils was retrospectively compared to surgical repair at Cleveland Clinic Foundation.

         

    Procedural and recovery costs for 36 patients, aged 13 months to 28 years, who had coil or surgical closure of PDA between 1993 and 1996, were determined and compared.

        

    The average cost of coil occlusion was 38% lower than surgical closure. But 17% of patients with coil occlusion had residual leaks at an average of 6 months after the procedure. There were no other short or long term complications in both groups and there were no deaths.

        

    Coil occlusion of PDA is a feasible, cheaper alternative to surgical repair.

         

  • Scott
    Gottlieb

    News : b Blockers Improve Bypass Surgery Survival
    Rates


    BMJ, 11 May, 02, Vol.324, pg.1118

      

    Patients who take b blockers before coronary artery
    bypass surgery can increase their odds of surviving,
    a new study says.

     

    The study found that 2.8% of patients who took b
    blockers before surgery died within a month,
    compared with 3.4% of patients who did not take the
    drugs.

      



Cardiac Surgery in Solid Organ Transplant Recipients



 

  • Mitruka
    SN, Griffith BP, Kormos RL, et al


    Cardiac Operations in Solid-organ Transplant Recipients


    Ann Thorac Surg 64: 1270-1278, 1997

         


    In recent years, the number of patients receiving solid organ transplants has steadily increased. So too have the numbers of such patients who later require cardiac surgery. Little is known about how best to approach such cases. The authors report their experiences in such situations.

         


    The subjects were 64 organ transplant recipients [ 46 men and 18 women; mean age 53 years] who underwent 66 cardiac procedures. Half the patients had diabetes and all but 2 had hypertension. The organ transplants involved were kidney in 40, liver in 16, heart in 5, lung in 2 and a combined liver and lung in 1. A mean of 53 months separated organ transplantation and cardiac surgery. The cardiac procedures were coronary artery bypass grafting in 30, valve replacement in 24, and aortic repair in 4. All patients were taking immunosuppresive drugs and blood levels were monitored throughout the perioperative period to maintain
    immunosuppression. Allograft function and rejection were also monitored throughout the hospital stay and treated if needed by pulse steroids.

         


    Two patients died [3%] within 30 days of cardiac surgery; one because of sepsis and one
    as a result of cardiac arrest. Seven patients [11%] died between 7 weeks and 26 months after cardiac surgery, but none of these
    deaths were attributed to a cardiac cause. Preoperatively 16 patients [25%] had chronic renal failure; 13 of these were renal transplant recipients. Postoperatively 7 of the renal transplant recipients [54] had renal failure and required
    hemodialysis; 4 improved by discharge but 3 experienced permanent allograft loss. Furthermore 3 other patients had transient graft rejection that was successfully treated with pulse steroids. 

         


    Overall none of the 17 liver transplant recipients experienced graft rejection or 

    failure; 1 of the 7 heart or lung transplant recipients experienced rejection; 7 of the 40 kidney transplant recipients experienced temporary [4] and permanent [3] allograft failure and 2 experienced rejection. Other major complications included infections [12 patients or 19%], and bleeding that required re-exploration [16%]; complications were most common in the kidney transplant recipients. At a mean follow-up of 22 months 5o of 55 surviving patients [91%] were alive without recurrent cardiac disease.

         


    Infections and bleeding complications were short term but not insignificant; these were likely related to immunosuppression and other co-morbid conditions. Permanent graft failure and rejection rates were low and mortality rates were comparable with those of non-transplant receiving patients undergoing cardiac surgery. Thus, when appropriate precautions are taken organ transplant recipients can have safe cardiac surgery.

Cardiac
Surgery and Anesthesiology – Renal Complications


       

  • CM Mangano 

    Renal Dysfunction After Myocardial Revascularization; Risk Factors, Adverse Outcomes and Hospital Resource Utilization

    Ann Intern Med 128: 194-203, 1998

        

    The effects of Cardiac surgery on renal function remain unclear. Renal function abnormalities can result from nonpulsatile blood flow, increased catecholamine and inflammatory mediator levels, renal embolic insults and release of free hemoglobin from traumatized erythrocytes. Renal function was studied in a large population of patients undergoing cardiopulmonary bypass and myocardial revascularization.

        

    The study included 2222 patients undergoing myocardial revascularization at 24 research hospitals. Their rates of postoperative renal failure [defined as a need for dialysis] and of renal dysfunction [defined as a postoperative serum creatinine level of 177 (mol/L or greater and an increase in serum creatinine of 62 (mol/L or greater from the preoperative to postoperative period] were assessed.

         

    Postoperative renal dysfunction ocurred in 7.7% and renal failure in 1.4% of patients. The mortality rate of 0.9% for patients with no renal complications was 19% for those with renal dysfunction and 63% for those with renal failure. The risk of renal failure increased with age: it doubled for those in their 70s and trebled for those in their 80s. Factors associated with renal dysfunction were Type I diabetes mellitus, a preoperative glucose level of greater than 16.6 (mol/L. Congestive heart failure, previous coronary bypass grafting and a preoperative creatinine level of 124 to 177 ( mol/L. More than 80% of patients with renal dysfunction had intraoperative or postoperative hemodynamic instability or hemorrhage.

         

    The study shows an 8% rate of renal dysfunction or failure in patients undergoing myocardial revascularization. Renal risk is associated with patient related factors, probably reflecting diffuse atherosclerosis. These findings have implications for preoperative communication of risk, treatment with potential nephrotoxic drugs and surgical technique.

         

Cardiovascular
Surgery


     

  • RI Katz, JM Bernhart, G Ho, et al

    A survey on the Intended Purposes and Perceived Utility of Preoperative Cardiology Consultation

    Anesth Analg 87:830-836, 1998

         

    Although surgeons and anesthesiologists often request cardiology consultations for patients with cardiovascular disease, no studies have documented the reasons behind these consultations or their effect on patient management. A study was designed to determine what surgeons, anesthesiologists and cardiologists think is important to obtain from a cardiology consultation and what effect any recommendations have on perioperative management. 

          

    A multiple-choice survey was developed from a focus group session conducted among 6 anesthesiologists and tested on groups of additional anesthesiologists, surgeons and cardiologists. The survey was sent to 1200 randomly selected physicians in these specialties [400 of each group]. Additional data were obtained from the charts of 55 consecutive patients who received preoperative cardiology consultations. 

         

    The overall response to the survey was 33.4% and opinions differed substantially about the importance and purposes of a cardiology consultation. Most cardiologists and surgeons, but not anesthesiologists, regarded intraoperative monitoring, clearing the patient for surgery and advising about the safest type of anesthesia as important. A majorityof surgeons [80.2%] but few anesthesiologists [16.6%], felt obligated to follow a cardiologist’s recommendations. Review of the 55 cardiology consultations found preoperative evaluation to be the most commonly stated purpose. Nearly 40% of the consultations contained no recommendation for changes in patient care or medication, and most advice offered about intraoperative management or cardiac drugs was ignored; of the 87 recommendations relating to preoperative management, however, 71 were followed [81.6%] There was disagreement among the specialists about which physician had primary authority to declare that an elective case may proceed.

          

    Anesthesiologists, cardiologists and surgeons differ considerably in their o pinions about the purpose and value of cardiology consultations. Many of these consultations appear to be requested for procedural reasons rather than to obtain responses to specific medical questions.

            

Cardiography

Echocardiography Impact of Transoesophageal Echocardiography
on Adult Cardiac Surgery



         

  • Sutton DC, Klugcr R


    Intraoperative Transoesophageal Echocardiography : Impact on Adult Cardiac Surgery


    Anaesth Intensive Care 26: 287-293, 1998

         


    Intraoperative transoesophageal echocardiography [TEE] is a powerful monitoring and diagnostic tool for left ventricular volume and function. Although the importance of TEE is widely recognized for mistral valve repair and complex congenital heart surgery, its usefulness during routine adult cardiac surgery remains controversial. The impact of intraoperative TEE on routine cardiac surgical management of adult patients was examined.

         


    The influence and impact of intraoperative TEE on results in the management of 238 consecutive patients aged between 23 and 84 years, operated over a two year period were examined.

         


    Routine TEE examinations were performed in 184 and at the specific request of the cardiologists in 54 patients. Of the routine TEE examinations 21% had significant findings and of the request TEE examinations 98% had significant findings; all these patients had different or additional operative procedures performed than were previously contemplated.

            


Pediatric Cardiac Surgery


     

  • Hannan EL, Racz M, Kavey RE et al


    Pediatric Cardiac Surgery: The effect of Hospital and Surgeon Volume on In Hospital Mortality


    Pediatrics 101: 963-969, 1998

         


    An inverse relationship between adverse outcomes for certain types of patients and the amount of experience of health care providers in treating such patients has been documented. The relationship between in-hospital mortality and both surgeon and hospital volume for pediatric cardiac surgery in New York State between 1992 and 1995 was retrospectively analyzed.

         


    The information came from the part of New York’s Surgery Reporting System database dedicated to pediatric cardiac surgery, which comprises all 7169 pediatric cardiac surgeries performed from 1992 to 1995 in the 16 New York State approved and certified hospitals. The risk-adjusted mortality rates for hospital and surgeon volume ranges were calculated with adjustments made for severity of illness.

         


    After controlling for severity of illness, hospitals with annual pediatric cardiac surgical volumes of less than 100 cases had significantly higher mortality rates than hospitals with volumes of 100 or more. Surgeon with annual volumes of less than 75 cases had significantly higher mortality rates than surgeons with annual volumes of 75 or more.

         


    Both the annual hospital and surgeons volume were found to be significantly related to in-hospital mortality of cardiac surgery patients in this population-based retrospective study, even after controlling for patient age, procedure complexity and other clinical risk factors. What is even more significant, these differences persisted even with low complexity pediatric cardiac surgery procedures.

          



 

   

Speciality Spotlight

   

   
Surgery
   

 

Cardiac Surgery
  

  • Gundry SR, Romano MA, Shattuck OH, et al [ Loma Linda Univ, Calif.]
    Seven Year follow-up of Coronary Artery Bypasses Performed with and Without Cardiopulmonary Bypass
    J Thorac Cardiovasc Surg 115: 1273-1278, 1998
         
    To decrease the morbidity and hospitalization associated with coronary artery bypass grafting [CABG] by cardiopulmonary bypass [CPB], surgeons revascularize the beating heart [BH] without CPB. Patients treated by the same surgeons, by both the techniques, were compared and long-term survival and intervention-free outcomes were assessed.
     
    Between June 1989 and July 1990, 112 patients had CABG with CPB and 107 patients had CABG on the beating heart [CABG on BH], at the hands of three surgeons. The average age and risk factors were identical for the two groups. Patients undergoing CABG with CPB had an average of 3.2 grafts vs 2.4 grafts in the other group.
     
    At a seven year follow-up 79% of the former group and 80% of the latter group were alive.  Cardiac deaths occurred in 9% in the former group vs 12% of the latter. However, 16% of patients who had CABG with CPB, required catheterization for their symptoms as against 30% of patients who had CABG on BH. Angioplasty or secondary CABG was required in 7% of the former as against 20% of the latter group.
     
    Thus patients with CABG on BH had twice as many requiring repeat investigations and thrice as many interventions as compared to the patients who had CABG under  CPB.
      

  • Pick AW, Orszulak TA, Anderson BJ, et al [Mayo Clinic, Rochester, Minn]
    Single Versus Bilateral Internal Mammary Artery Grafts : 10-Year Out-come Analysis
    Ann Thorac Surg 64: 599-605, 1997

    The use of the left internal mammary artery [IMA] to bypass the left anterior descending coronary artery has been associated with superior graft patency, reduced cardiac events and enhanced survival, so some surgical groups have begun using both IMAs for revascularization. To determine whether use of both IMAs confers further advantage to patients at bypass surgery, a group of patients with bilateral IMA [BIMA] bypass procedures was compared to a group of single IMA [SIMA] bypass procedures. Beginning in January 1984 and continuing for 24 months, 160 patients with multivessel disease had coronary revascularization procedures with BIMA grafts plus saphenous venous grafts, and 160 patients had saphenous grafts alone. During an extended time to May 1986, a matched group of 161 patients with a SIMA grafts plus supplementary saphenous venous grafts, operated on by the same surgeon were identified. The three groups of patients were matched for gender, preoperative angina, priority status, extent of coronary artery disease, left ventricular function, and number of distal anastomoses. Diabetes was more common in the SIMA group.  Operative mortality was 0.6% for the SIMA group and nil for the BIMA group.
      
    The average follow-up of 10 years, revealed lower late cardiac mortality in the BIMA group; survivals at 10 years were 75% for the SIMA group vs 85% for the BIMA group. Diabetes, age, and lower ejection fractions were the main factors responsible for late cardiac deaths in all the patients.
      
    Bilateral internal artery grafts were associated with reduced risk of angina recurrence, late myocardial infarction, and other late cardiac events after revascularization. Larger studies are suggested to confirm the findings.

  • Tatoulis J, Buxton BF, Fuller JA [Univ of Melbourne, Australia]
    Results of 1454 Free Right Internal Thoracic Artery To – Coronary Artery Grafts
    The patients had an average age of 59. Eight percent had non-insulin-dependent diabetes and 0.5% had insulin-dependent diabetes. Decreased left ventricular ejection fraction was present in 12%, and unstable angina in 9.9%. In eleven patients, FRITA was the only graft. There was an average of 3.3 distal anastomoses per patient. Bypass time was about 69 minutes and aortic clamp time about 49 minutes.
         
    Operative mortality was 0.9%, stroke occurred in 1%; and myocardiac infarct in 1.3% of the patients. Complications included sternal infection in 1.2%, and reoperation for hemorrhage in 1.6%. Survival at 5 years was 96% and at 7 years 94%. In 71 patients followed up for an average of 42 months, FRITA was widely patent in 67, displayed a string sign in 3, and occlusion in 1. The right internal thoracic artery can be safely and successfully used as a free graft for myocardial revascularization. Short and long term results were similar to those of single thoracic artery grafting.
          

  • Mohammad Bashar Izzat Loay S. Kabbani, Gianni D. Angelni
    Minimal-access and Minimally invasive Cardiac Surgery
    Recent Advances in Surgery-23, Year-2000
          
    Median sternotomy has remained the standard approach for most open-heart procedures because it provides easy exposure of the entire heart and allows for the various cardiopulmonary by pass and myocardial protection techniques. 
         
    It is fitting at the beginning to define ‘minimally-invasive’ and ‘minimal access” surgical techniques.
        
    Minimizing the ‘invasiveness’ of surgery implies reducing the peri-operative morbidity defined by measures of clinical outcome in comparison to conventional techniques. 
          
    Extracorporeal circulation is another significant cause of patient morbidity. Hence avoiding the use of cardiopulmonary bypass, regardless of the type of surgical incision, is another minimally invasive approach in cardiac surgery.
          
    Currently employed minimal-access approaches to heart operations can be broadly classified into: [I] direct-vision techniques through limited incisions; and [ii] video-assisted approaches using endoscopic methods.
          
    At present, the partial stenotomy incision is the most commonly used minimal-access approach for intra-cardiac operations.
          
    It has many of the advantages of median sternotomy, the incision is easily opened and closed, provides excellent access, allows for standard cardiopulmonary bypass techniques and can be easily converted to full sternotomy in troublesome techniques and can be easily converted full sternotomy in troublesome cases.
          
    With a upper partial sternotomy, the sternum is split from the sternal notch to the level of the third intercostal space.
           
    Alternatively, a lower partial sternotomy incision can be used, dividing the sternum from the xiphoid process up the level of the second rib, and terminating the sternal split into the left 2nd intercostal space.
           
    Minimizing access has been advantageous in clinical experience. For the surgeon, opening and closing the chest is easier and faster, and mediastinal blood loss is significantly reduced.
          
    These patients resume normal activities earlier than those who undergo the conventional operation.
           
    Postoperative pain is also reported to be reduced, both in hospital and after discharge.
           
    Another potential advantage of the minimal access approach is that the pericardium is not fully opened; hence re-operation should be easier and safer.
           
    The potential disadvantages of these procedures should be considered as well.
           
    Paradoxical motion of the chest wall, particularly during coughing, has been observed in most patients.
           
    Video-assistance remains limited to a few applications in cardiac surgery due to the complexities of cardiac procedures.
          
    The only established role for the video-assisted technique at present is in thoracoscopic mitral valve surgery, but it can also be used for harvesting the internal mammary artery in preparation for the minimally invasive direct coronary artery bypass [MIDCAB] procedure.
          
    Coronary artery bypass grafting without cardiopulmonary bypass is a surgical strategy that has gained increasing popularity.
          
    Patients poorly tolerate the side effects of hypotensive non-pulsatile extracorporeal perfusion and systemic cooling.
          
    Early experience with coronary revascularization without cardiopulmonary bypass has been very encouraging, and is now the technique of choice for routine coronary grafting.
          
    The concepts of minimal-access and minimally invasive heart surgery advantageous and deserve further investigation and development.
        

  • Robicsek F., Cook JW, Rizzoni W [Carolina Med Ctr, Charlotte, NC]
    Sternoplasty for Incomplete Sternum Separation
    J Thorac Cardiovasc Surg 116: 361-362, 1998
         
    The authors have previously reported a technique for surgical repair of poststernotomy separation. In the sternum weaving technique, persistent bilateral double-row sutures are placed, and transverse sutures are used to reunite the sternum halves, buttressed by the double axial suture lines. This technique is highly useful for patients with separation along the complete length of the sternum,but some patients have separation only of the lower portion of the sternum. In these cases the full sternum may sometimes be divided just to reapproximate the lower portion. A modified technique for reapproximation of the separated lower portion of the sternum has been described.
     
    This modified sternoplasty technique can be used in cases of partial postoperative sternum separation. This approach was successful in several patients with chronic, noninfected partial sternum separations. All patients showed good results, with early discharge from the hospital.
         

  • Fang WC, Helm RE, Kreiger KH, et al [Univ. of Massachusetts, Worcester, Cornell Univ, New York; North Shore Univ. Hosp., Manhasset, NY]
    Impact of Minimum Hematocrit During Cardiopulmonary Bypass on Mortality in Patients Undergoing Coronary Artery Surgery
    Circulation 96 [suppl II] : II-194-II-199, 1997
         
    Over the years variety of measures have been used to reduce the need for blood transfusion during coronary artery bypass grafting [CABG]. The hematocrit commonly falls to a low level in patients undergoing cardiopulmonary bypass [CPB] and there is a debate over the minimum safe hematocrit level during this procedure. The mortality effect of the minimum hematocrit level achieved during CPB was investigated.
         
    The analysis included 1638 sequential patients undergoing CABG over 42 months. Patients requiring valve replacement or other concurrent surgical procedures were excluded.
          
    Minimum hematocrit levels reached during PCB was analyzed, along with 31 preoperative risk factors for effect on postoperative mortality.
          
    The initial multiple logistic regression model identified 8 preoperative risk factors as independent predictors of postoperative mortality: shock, renal failure, ventricular arrhythmia, previous open heart surgery, IV nitroglycerine administration, congestive heart failure, aortoiliac disease, and older age. In a further model, minimum hematocrit during CPB was independently associated with mortality risk.
           
    With adjustment for other factors, patients with minimum hematocrit of 14% or below had an increased probability of risk-adjusted mortality With high risk patients, minimum hematocrit of 17% or lower had significantly higher risk of postoperative mortality.
           
    Thus extent to which hematocrit falls during CPB is an independent risk factor for postoperative mortality.
         

  • Johnson D, Perrault H, Vobecky SJ, et al [ Ste-Justine Hospital, Montreal; McGill Univ, Montreal]
    Influence of the Postoperative Period and Surgical Procedure on Ambulatory Blood Pressure -Determination of Hypertension Load After Successful Surgical Repair of Coarctation of the Aorta 
    Eur Heart J 19: 638-646, 1998
         
    The monitoring of blood pressure after surgical correction of coarctation of the aorta is usually performed using a sphygmomanometer. Ten to 40% of patients who undergo an apparently successful repair of coarctation of aorta have hypertension 10 to 20 years later. The hypertension load was quantified using 24-hour ambulatory blood pressure monitoring in patients less than 10 years and more than 10 years after surgery. The type of surgical repair was also assessed.
        
    Ambulatory blood pressure recordings were taken using an Accutracker II monitor every 30 minutes in the daytime and every one hour at night. Patients were grouped in two groups according to the period elapsed after surgery. Group 1 less than 10 years and Group 2 more than 10 years after surgery. A group of healthy adolescents were used as a control group. Of the twenty-one patients 12 had end-to-end anastomosis and 9 left subclavian artery angioplasty for correction of the coarctation.
        
    Compared with the controls all operated cases showed higher day and night systolic and diastolic blood pressures. Daytime systolic hypertension occurred in 20% in Group 1 and in 49% in Group 2. There was no diastolic hypertension. There were also no differences in blood pressure recordings in the two types of operation.
        
    Patients undergoing repair for coarctation of aorta develop hypertension with time and need constant monitoring.
          

  • Shaffer KM, Mullins CE, Grifka RG, et al [ Baylor College of Medicine, Houston; Texas Children’s Hospital, Houston]
    Intravascular Stents in Congenital Heart Disease: Short and Long-Term Results From a Large Single-Center Experience
    J Am Coll Cardiol 31: 661-667, 1998

    Intravascular stents for the treatment of patients with congenital heart disease and vascular stenoses were evaluated by Food and Drug Administration [FDA] phase 1 and 2 clinical trials at Texas Children’s Hospital. Results of only FDA-approved investigational device exemption study of balloon-expandable stents in patients with congenital heart disease and vascular stenoses were reported.

    All patients enrolled in the study had stenoses requiring treatment. Stents were placed in 3 groups of patients: those with postoperative pulmonary artery [PA] stenoses, congenital PA stenoses, and stenoses of systemic veins/venous anastomoses. A total of 347 stents were placed in 200 patients between September 1989 and June 1995. The Palmaz stent was used in all cases. Median patient age at implantation was 10.5 years. Data were collected before and after stent implantation and at follow-up.

    All three groups showed marked fall in gradients across the stenoses, and marked increase in vessel diameters. Right ventricular pressure decreased in both congenital as well as postoperative pulmonary stenoses, and perfusion to the lungs increased considerably. The changes were seen steady at follow-up catheterization done at a mean of 14 months after implantation. There were 4 cases of stent migration in the earlier cases and three patients had restenosis. Two deaths were directly attributed to stent implantation.

    Intravascular stents proved to be safe and effective in the management of PA stenoses and other vascular anastomoses; there is no long-term morbidity and the favourable results appear immediately and continue into follow-up.
        

  • Daniels CJ, Cassidy SC, Teske DW, et al [ Columbus Children’s Hospital and Ohio State Univ, Columbus]
    Reopening After Successful Coil Occlusion for Patent ductus Arteriorus
    J Am Coll Cardiol 31: 444-450, 1998
      
    A study of children who had undergone successful coil occlusion of patent ductus arteriorus [PDA] was conducted to determine the frequency of reopening and the factors that may predict reopening.
       
    The patients underwent percutaneous transarterial PDA coil occlusion. The length and diameter of PDAs were determined.Doppler echocardiography was performed within 24 hours of coil occlusion to document success. Patients were reevaluated at 12 months.
       
    Coil occlusion was performed in 22 children with a median age of 4.9 years. Clinical success with loss of continuous murmur was achieved in 91% and in 90% doppler echocardiography was negative for PDA shunting. Five patients [22%] were seen to have reopening at follow-up. These patients had larger minimal diameter of 1.4 mm vs 1.2 mm and shorter PDA length 2.9 mm vs 7.1 mm. A ngiographic appearance in 3 of these patients showed type B PDA [conical with short ductal ampulla].
       
    Thus despite successful coil occlusion for PDA, reopening is common. Previous reports have indicated that success is associated with minimal diameter of the PDA. In particular failure may occur with a wide-diameter and short length PDA. Angiographic type B PDA is also associated with reopening. 
         

  • PreitoLR, DeCamillo DM, Konrad DJ, et al [ Cleveland Clinic Found, Ohio]
    Comparison of Cost and Clinical Outcome Between Transcatheter Coil Occlusion and Surgical Closure of Isolated Patent Ductus Arteriorus
    Pediatrics 101: 1020-1024, 1998
        
    Transcatheter closure of patent ductus arteriorus [PDA] using Gianturco coils was retrospectively compared to surgical repair at Cleveland Clinic Foundation.
         
    Procedural and recovery costs for 36 patients, aged 13 months to 28 years, who had coil or surgical closure of PDA between 1993 and 1996, were determined and compared.
        
    The average cost of coil occlusion was 38% lower than surgical closure. But 17% of patients with coil occlusion had residual leaks at an average of 6 months after the procedure. There were no other short or long term complications in both groups and there were no deaths.
        
    Coil occlusion of PDA is a feasible, cheaper alternative to surgical repair.
         

  • Scott Gottlieb
    News : b Blockers Improve Bypass Surgery Survival Rates
    BMJ, 11 May, 02, Vol.324, pg.1118
      
    Patients who take b blockers before coronary artery bypass surgery can increase their odds of surviving, a new study says.
     
    The study found that 2.8% of patients who took b blockers before surgery died within a month, compared with 3.4% of patients who did not take the drugs.
      

Cardiac Surgery in Solid Organ Transplant Recipients
 

  • Mitruka SN, Griffith BP, Kormos RL, et al
    Cardiac Operations in Solid-organ Transplant Recipients
    Ann Thorac Surg 64: 1270-1278, 1997
         
    In recent years, the number of patients receiving solid organ transplants has steadily increased. So too have the numbers of such patients who later require cardiac surgery. Little is known about how best to approach such cases. The authors report their experiences in such situations.
         
    The subjects were 64 organ transplant recipients [ 46 men and 18 women; mean age 53 years] who underwent 66 cardiac procedures. Half the patients had diabetes and all but 2 had hypertension. The organ transplants involved were kidney in 40, liver in 16, heart in 5, lung in 2 and a combined liver and lung in 1. A mean of 53 months separated organ transplantation and cardiac surgery. The cardiac procedures were coronary artery bypass grafting in 30, valve replacement in 24, and aortic repair in 4. All patients were taking immunosuppresive drugs and blood levels were monitored throughout the perioperative period to maintain immunosuppression. Allograft function and rejection were also monitored throughout the hospital stay and treated if needed by pulse steroids.
         
    Two patients died [3%] within 30 days of cardiac surgery; one because of sepsis and one as a result of cardiac arrest. Seven patients [11%] died between 7 weeks and 26 months after cardiac surgery, but none of these deaths were attributed to a cardiac cause. Preoperatively 16 patients [25%] had chronic renal failure; 13 of these were renal transplant recipients. Postoperatively 7 of the renal transplant recipients [54] had renal failure and required hemodialysis; 4 improved by discharge but 3 experienced permanent allograft loss. Furthermore 3 other patients had transient graft rejection that was successfully treated with pulse steroids. 
         
    Overall none of the 17 liver transplant recipients experienced graft rejection or 
    failure; 1 of the 7 heart or lung transplant recipients experienced rejection; 7 of the 40 kidney transplant recipients experienced temporary [4] and permanent [3] allograft failure and 2 experienced rejection. Other major complications included infections [12 patients or 19%], and bleeding that required re-exploration [16%]; complications were most common in the kidney transplant recipients. At a mean follow-up of 22 months 5o of 55 surviving patients [91%] were alive without recurrent cardiac disease.
         
    Infections and bleeding complications were short term but not insignificant; these were likely related to immunosuppression and other co-morbid conditions. Permanent graft failure and rejection rates were low and mortality rates were comparable with those of non-transplant receiving patients undergoing cardiac surgery. Thus, when appropriate precautions are taken organ transplant recipients can have safe cardiac surgery.

Cardiac Surgery and Anesthesiology – Renal Complications
       

  • CM Mangano 
    Renal Dysfunction After Myocardial Revascularization; Risk Factors, Adverse Outcomes and Hospital Resource Utilization
    Ann Intern Med 128: 194-203, 1998
        
    The effects of Cardiac surgery on renal function remain unclear. Renal function abnormalities can result from nonpulsatile blood flow, increased catecholamine and inflammatory mediator levels, renal embolic insults and release of free hemoglobin from traumatized erythrocytes. Renal function was studied in a large population of patients undergoing cardiopulmonary bypass and myocardial revascularization.
        
    The study included 2222 patients undergoing myocardial revascularization at 24 research hospitals. Their rates of postoperative renal failure [defined as a need for dialysis] and of renal dysfunction [defined as a postoperative serum creatinine level of 177 (mol/L or greater and an increase in serum creatinine of 62 (mol/L or greater from the preoperative to postoperative period] were assessed.
         
    Postoperative renal dysfunction ocurred in 7.7% and renal failure in 1.4% of patients. The mortality rate of 0.9% for patients with no renal complications was 19% for those with renal dysfunction and 63% for those with renal failure. The risk of renal failure increased with age: it doubled for those in their 70s and trebled for those in their 80s. Factors associated with renal dysfunction were Type I diabetes mellitus, a preoperative glucose level of greater than 16.6 (mol/L. Congestive heart failure, previous coronary bypass grafting and a preoperative creatinine level of 124 to 177 ( mol/L. More than 80% of patients with renal dysfunction had intraoperative or postoperative hemodynamic instability or hemorrhage.
         
    The study shows an 8% rate of renal dysfunction or failure in patients undergoing myocardial revascularization. Renal risk is associated with patient related factors, probably reflecting diffuse atherosclerosis. These findings have implications for preoperative communication of risk, treatment with potential nephrotoxic drugs and surgical technique.
         

Cardiovascular Surgery
     

  • RI Katz, JM Bernhart, G Ho, et al
    A survey on the Intended Purposes and Perceived Utility of Preoperative Cardiology Consultation
    Anesth Analg 87:830-836, 1998
         
    Although surgeons and anesthesiologists often request cardiology consultations for patients with cardiovascular disease, no studies have documented the reasons behind these consultations or their effect on patient management. A study was designed to determine what surgeons, anesthesiologists and cardiologists think is important to obtain from a cardiology consultation and what effect any recommendations have on perioperative management. 
          
    A multiple-choice survey was developed from a focus group session conducted among 6 anesthesiologists and tested on groups of additional anesthesiologists, surgeons and cardiologists. The survey was sent to 1200 randomly selected physicians in these specialties [400 of each group]. Additional data were obtained from the charts of 55 consecutive patients who received preoperative cardiology consultations. 
         
    The overall response to the survey was 33.4% and opinions differed substantially about the importance and purposes of a cardiology consultation. Most cardiologists and surgeons, but not anesthesiologists, regarded intraoperative monitoring, clearing the patient for surgery and advising about the safest type of anesthesia as important. A majorityof surgeons [80.2%] but few anesthesiologists [16.6%], felt obligated to follow a cardiologist’s recommendations. Review of the 55 cardiology consultations found preoperative evaluation to be the most commonly stated purpose. Nearly 40% of the consultations contained no recommendation for changes in patient care or medication, and most advice offered about intraoperative management or cardiac drugs was ignored; of the 87 recommendations relating to preoperative management, however, 71 were followed [81.6%] There was disagreement among the specialists about which physician had primary authority to declare that an elective case may proceed.
          
    Anesthesiologists, cardiologists and surgeons differ considerably in their o pinions about the purpose and value of cardiology consultations. Many of these consultations appear to be requested for procedural reasons rather than to obtain responses to specific medical questions.
            

Cardiography
Echocardiography Impact of Transoesophageal Echocardiography on Adult Cardiac Surgery

         

  • Sutton DC, Klugcr R
    Intraoperative Transoesophageal Echocardiography : Impact on Adult Cardiac Surgery
    Anaesth Intensive Care 26: 287-293, 1998
         
    Intraoperative transoesophageal echocardiography [TEE] is a powerful monitoring and diagnostic tool for left ventricular volume and function. Although the importance of TEE is widely recognized for mistral valve repair and complex congenital heart surgery, its usefulness during routine adult cardiac surgery remains controversial. The impact of intraoperative TEE on routine cardiac surgical management of adult patients was examined.
         
    The influence and impact of intraoperative TEE on results in the management of 238 consecutive patients aged between 23 and 84 years, operated over a two year period were examined.
         
    Routine TEE examinations were performed in 184 and at the specific request of the cardiologists in 54 patients. Of the routine TEE examinations 21% had significant findings and of the request TEE examinations 98% had significant findings; all these patients had different or additional operative procedures performed than were previously contemplated.
            

Pediatric Cardiac Surgery
     

  • Hannan EL, Racz M, Kavey RE et al
    Pediatric Cardiac Surgery: The effect of Hospital and Surgeon Volume on In Hospital Mortality
    Pediatrics 101: 963-969, 1998
         
    An inverse relationship between adverse outcomes for certain types of patients and the amount of experience of health care providers in treating such patients has been documented. The relationship between in-hospital mortality and both surgeon and hospital volume for pediatric cardiac surgery in New York State between 1992 and 1995 was retrospectively analyzed.
         
    The information came from the part of New York’s Surgery Reporting System database dedicated to pediatric cardiac surgery, which comprises all 7169 pediatric cardiac surgeries performed from 1992 to 1995 in the 16 New York State approved and certified hospitals. The risk-adjusted mortality rates for hospital and surgeon volume ranges were calculated with adjustments made for severity of illness.
         
    After controlling for severity of illness, hospitals with annual pediatric cardiac surgical volumes of less than 100 cases had significantly higher mortality rates than hospitals with volumes of 100 or more. Surgeon with annual volumes of less than 75 cases had significantly higher mortality rates than surgeons with annual volumes of 75 or more.
         
    Both the annual hospital and surgeons volume were found to be significantly related to in-hospital mortality of cardiac surgery patients in this population-based retrospective study, even after controlling for patient age, procedure complexity and other clinical risk factors. What is even more significant, these differences persisted even with low complexity pediatric cardiac surgery procedures.
          

 

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