Combined Procedure of Coronary Artery Bypass Grafting and Valve Repair

The safety of combined operative procedures for valvular and coronary artery disease was reviewed in 27 patients. Twelve patients had aortic valve disease and 15 had mitral valve disease. Forty-seven coronary artery reconstructions were performed, an average of 1.7 per patient. Twenty-two patients underwent valve replacement and 5 had valvuloplasty. Congestive heart failure was the major symptom in 20 patients, and angina was the major symptom in 7. Eight of the patients with congestive heart failure had no angina, but significant coronary stenoses were demonstrated at routine coronary angiography.Coronary reconstruction was performed before valve repair. Two patients died postoperatively (a hospital mortality of 7.4%), and there were 4 late deaths from 2 to 28 months postoperatively. There were no postoperative myocardial infarctions.Contrary to previous reports, coronary artery reconstruction and valve repair need not be associated with an increased risk. Protection of the myocardium by coronary perfusion through reconstructed coronary arteries enables valve repair to be done without greater risk than valve repair alone. All patients considered for valve repair should have coronary angiography.     

A new technique for perfusion of the heart during aortic valvular surgery on a beating heart

A new technique of perfusion of the heart during aortic valvular and combined aortic valvular and coronary artery surgery on the beating heart is presented. The inflow for perfusion is via a dual system: the coronary sinus is perfused with blood from a calibrated centrifugal pump connected to the oxygenator; the coronary ostia are perfused with blood from the ascending aortic cannula. The advantages of this new technique of perfusion of the heart are discussed. A new technique of perfusion of the heart during aortic valve surgery is presented, utilizing a dual system: one utilizing a pump, the other derived from the aortic cannula.     

Aortic valve replacement with frame-supported autologous fascia lata grafts. II. Clinical and laboratory findings.

Thirty-five patients with a frame-supported autologous fascia lata graft implanted in the aortic annulus were investigated 11 to 36 months after operation. The group comprised 7 patients with pure aortic stenosis, 11 with combined stenosis and incompetence and 17 with pure aortic incompetence. Seven patients had concommitant mitral valve disease. The follow-up investigation included ECG, a work test on a bicycle ergometer, dynamic spirometry, roentgenological heart volume determination and haematological "screening tests" for intravascular haemolysis. Concomitant with a marked subjective improvement of the patients, there was a considerable objective improvement, as judged by physical working capacity, ECG signs of left ventricular hypertrophy and heart volume. The serum haptoglobin values were somewhat lower postoperatively (mean value 44 mg%), but no ahaptoglobinaemia occurred. Thus, no definite signs of intravascular haemolysis were noted. No thrombo-embolism occurred within this observation period, despite the fact that none of the patients with isolated aortic valve replacement were treated with anticoagulants. This investigation shows that a frame-supported autologous fascia lata valvular graft in the aorta can function well during a period of up to 3 years.     

Leakage test during mitral valve repair

Mitral valve repair is the preferred surgical treatment for mitral regurgitation. Cardiac surgeons must increasingly pursue high-quality mitral valve repair, which ensures excellent long-term outcomes. Intraoperative assessment of a competency of the repaired mitral valve before closure of the atrium is an important step in accomplishing successful mitral valve repair. Saline test is the most simple and popular method to evaluate the repaired valve. In addition, an “Ink test” can provide confirmation of the surface of coaptation, which is often insufficient in the assessment of saline test. There are sometimes differences between the findings of the leakage test in an arrested heart and the echocardiographic findings after surgery. Assessment of the mitral valve in an arrested heart may not accurately reflect its function in a contractile heart. Assessment of the valve on the beating heart induced by antegrade or retrograde coronary artery perfusion can provide a more physiological assessment of the repaired valve. Perfusion techniques during beating heart surgery mainly include antegrade coronary artery perfusion without aortic cross-clamping, and retrograde coronary artery perfusion via the coronary sinus with aortic cross-clamping. It is the most important point for the former approach to avoid air embolism with such precaution as CO₂ insufflation, left ventricular venting, and transesophageal echocardiography, and for the latter approach to maintain high perfusion flow rate of coronary sinus and adequate venting. Leakage test during mitral valve repair increasingly takes an important role in successful mitral valve reconstruction.     

Selective antegrade cardioplegic perfusion complicated by left main stem dissection

Selective antegrade coronary artery perfusion is a commonly used procedure to obtain myocardial preservation during cardiac surgery. This report describes a patient operated for severe aortic valve stenosis and insufficiency, mitral valve and tricuspid insufficiency. Cardioplegia was administered by selective antegrade coronary artery blood perfusion. Antegrade blood cardioplegia was complicated by dissection of the left coronary main stem. The dissection induced a myocardial infaction and the patient finally died due to heart failure.     

Different characteristics of postoperative heart failure after surgery for aortic stenosis and coronary disease

Objective—Postoperative heart failure (PHF) remains a major determinant of outcome after cardiac surgery. However, possible differences in characteristics of PHF after valve surgery and coronary surgery (CABG) have received little attention. Therefore, this issue was studied in patients undergoing aortic valve replacement (AVR) and CABG, respectively.

Design—Three hundred and ninety‐eight patients undergoing isolated AVR for aortic stenosis were compared with 398 patients, matched for age and sex, undergoing on‐pump isolated CABG. Forty‐five AVR and 47 CABG patients required treatment for PHF and these were studied in detail.

Results—The AVR group had longer aortic cross‐clamp time and higher rate of isolated right ventricular heart failure postoperatively. Myocardial ischemia during induction and perioperative myocardial infarction were more common in the CABG group. One‐year mortality was 8.9% in the AVR group vs 25.5% in the CABG group (p?=?0.05).

Conclusions—The incidence of PHF was similar in both groups but different characteristics were found. Isolated right ventricular failure and PHF precipitated by septicemia were more common in AVR patients. PHF was more clearly associated with myocardial ischemia and infarction in CABG patients, which could explain their less favorable survival.     

Author Index

During aortic valve surgery, cardioplegic solution is delivered through direct cannulation of both coronary ostia. Since this approach may cause an intimal injury leading to acute dissection or late ostial stenosis, we have evaluated retrograde coronary sinus perfusion (RCSP) as a means of delivering cardioplegia in 12 patients undergoing aortic valve replacement. The retroperfusion of the cardioplegic solution was performed with a balloon-tipped catheter inserted into the coronary sinus through the right atrium. The perfusion pressure averaged 40 mm Hg. Twelve patients undergoing antegrade coronary perfusion served as controls. Both groups were matched for preoperative and intraoperative data. The postoperative evaluation focused on hemodynamic status, as evidenced by serial measurements of right-sided pressures and cardiac output at 1, 6, 12, 18, and 24 hours after operation. The stroke volume index and the left ventricular and right ventricular systolic stroke work indexes were then calculated. There was no statistically significant difference between the two groups. We conclude that RCSP is a simple, safe, and effective means of cardioplegic protection during aortic valve surgery.     

Myocardial metabolism before and after valve replacement for aortic stenosis

AIM: Post ischemic disturbances of myocardial metabolism that may contribute to postoperative heart failure and are accessible to metabolic treatment have been identified early after coronary surgery. Knowledge derived from these studies may not be applicable to other patient groups. Therefore we studied myocardial energy metabolism in patients operated for isolated aortic stenosis. METHODS: Twenty patients undergoing isolated aortic valve replacement (AVR) because of aortic stenosis without significant regurgitation were studied before and immediately after surgery. Myocardial uptake of oxygen and energy substrates was assessed with coronary sinus catheter technique. RESULTS: Free fatty acids (FFA) were the main source of myocardial energy before and after AVR. A significant uptake of lactate was only recorded preoperatively. A significant uptake of glutamate of the same magnitude as previously described in coronary patients was found pre- and postoperatively. Postoperatively a relative decrease of myocardial oxygen extraction ratio (P<0.001) and oxygen consumption (P=0.14) by approximately 20% was observed. CONCLUSION: Preoperative and postoperative metabolic adaptation with substantial uptake of glutamate, previously claimed to be due to chronic or repetitive ischemia, was demonstrated. The results indicate that oxidative metabolism had not fully recovered when the procedure was completed. However, the potentially unfavorable postoperative metabolic state with predominant reliance on FFA as energy source was out-balanced by the unloading effect of AVR with a reduction in myocardial oxygen extraction.     

The effects of morphine anesthesia on blood requirements during and after valve replacement and coronary artery bypass grafting

A comparison of the effects of anesthetic doses of morphine—1 to 3 mg. per kilogram of body weight—and halothane—0.1 to 1.5%—was obtained by determining the blood requirements intraoperatively and 24 hours postoperatively of 105 patients, 45 of whom underwent elective aortic or mitral valve replacement with the remaining 60 undergoing aortocoronary bypass grafting procedures. Of the 51 patients receiving morphine, those who underwent aortic or coronary artery operations needed significantly more blood postoperatively; all required more blood postoperatively than did the 54 patients receiving halothane. Three of the patients who had coronary artery operations and 2 who underwent mitral valve replacement died during or within 24 hours of operation and thus were not included in the final study. We believe, therefore, that, when compared with halothane, morphine produces an increase in total vascular capacitance and that increased intraoperative and postoperative replacement of blood or other colloids is required in order to maintain myocardial filling pressures and outputs.     

Lung volume reduction surgery combined with cardiac interventions.

OBJECTIVE: Postoperative course and functional outcome were evaluated in patients who underwent lung volume reduction surgery (LVRS) or in combination with valve replacement (VR), percutaneous transluminal coronary angioplasty (PTCA), placement of a stent, or coronary artery bypass grafting (CABG). METHODS: Patients with severe bronchial obstruction and hyperinflation due to pulmonary emphysema were evaluated for lung volume reduction surgery. Cardiac disorders were screened by history and physical examination and assessed by coronary angiography. Nine patients were accepted for LVRS in combination with an intervention for coronary artery disease (CAD). In addition, three patients with valve disease and severe emphysema were accepted for valve replacement (two aortic-, one mitral valve) only in combination with LVRS. Functional results over the first 6 months were analysed. RESULTS: Pulmonary function testing demonstrates a significant improvement in postoperative FEV1 in patients who underwent LVRS combined with an intervention for CAD. This was reflected in reduction of overinflation (residual volume/total lung capacity (RV/TLC)), and improvement in the 12-min walking distance and dyspnea. Median hospital stay was 15 days (10-33). One patient in the CAD group died due to pulmonary edema on day 2 postoperatively. One of the three patients who underwent valve replacement and LVRS died on day 14 postoperatively following intestinal infarction. Both survivors improved in pulmonary function, dyspnea score and exercise capacity. Complications in all 12 patients included pneumothorax (n = 2), hematothorax (n = 1) and urosepsis (n = 1). CONCLUSION: Functional improvement after LVRS in patients with CAD is equal to patients without CAD. Mortality in patients who underwent LVRS after PTCA or CABG was comparable to patients without CAD. LVRS enables valve replacement in selected patients with severe emphysema otherwise inoperable.     

Survival and Cardiac Performance After Left Ventricular Aneurysmectomy

Reconstruction of the left ventricle was performed in 24 consecutive male patients with symptomatic, paradoxically expanding post-infarction ventricular aneurysms during the 13-year-period ending 1973. One patient also required prosthetic mitral valve replacement because of papillary muscle dysfunction and another patient patch closure of a post-infarction septal perforation. Four other patients underwent coronary artery bypass grafting in addition to the aneurysmectomy. All patients except 3 were seriously limited functionally, corresponding to capacity groups III and IV (N.Y.H.A.), and congestive heart failure refractory to medical therapy dominated the clinical status in most patients. A rather pronounced cardiomegaly, low physical working capacity, hypokinetic central circulation with small effective stroke volume and low cardiac output, elevated filling pressure and moderate pulmonary hypertension reflected serious impairment of LV-pump function.

Hospital mortality was 21% (5/24 patients) and closely related to the condition of the residual myocardium. There was no early mortality among patients undergoing combined procedures. All long-term survivors improved by at least one functional capacity group. The major late haemodynamic effects of aneurysmectomy were an increase in effective stroke volume and a decrease in LV-filling pressure at rest and during exercise, accompanied by a reduction or normalization of pulmonary hypertension, whereas the circulation usually remained hypokinetic. After surgery, the heart had regained much of its ability to increase stroke work during exercise, although cardiac performance was not restored to normal in the majority of patients. None of the patients suffered from thrombo-embolism postoperatively. The 5-year actuarial survival of 50% indicates a definite improvement over the natural history of left ventricular aneurysm.

It is evident from our experience and from the reports of others that surgery has a well-established position in the treatment of post-infarction LV-aneurysms with paradoxical expansion. Aneurysmectomy offers beneficial symptomatic and haemodynamic improvement and increases the chance of survival. The size of the residual LV-chamber, its blood supply and performance are important factors in the selection of candidates for surgery.     

Aortic valve replacement and aorta-coronary bypass surgery. Results with perfusion of proximal and distal coronary arteries.

The results in 80 patients undergoing simultaneous aortic valve replacement and aorta-coronary saphenous vein bypass grafting were analyzed to assess the effect of operative technique. The over-all operative mortality rate of 6.3% (five of 80) did not differ significantly from our results with aortic valve replacement alone. All patients who had isolated aortic valve replacement were operated upon with moderate hypothermia. The combined operation was performed in two ways. Thirty-one patients had aortic valve replacement prior to bypass grafting with intermittent coronary ostila perfusion. There were two deaths (6.5%), and five myocardial infarctions (16.1%) were diagnosed by standard electrocardiographic and enzyme criteria. More recently, 49 patients have undergone bypass grafting prior to aortic valve replacement. The proximal ends of the grafts were either anastomosed high on the aortic root or else individually cannulated to provide continuous distal perfusion during subsequent aortic valve replacement, with continuous coronary ostial perfusion. There were three operative deaths (6.1%) and one myocardial infarction (2.0%). The risk of combined aortic valve replacement and coronary bypass need be no greater than the risk of aortic valve replacement alone. Our experience suggests that myocardial perfusion distal to significant coronary artery stenoses reduces the risk of myocardial infarction in patients with coronary artery disease requiring aortic valve replacement.     

Poor long-term outcomes after carotid endarterectomy: a retrospective analysis of two portuguese centers

Objective—To evaluate the adherence to current guidelines for surgery in patients with aortic valve stenosis.

Design—From 1 January 1997 to 31 May 1999, 99 patients were accepted for aortic valve surgery with preserved left ventricular function and normal coronary angiogram. On admission for operation, 20 patients were evaluated regarding symptoms, exercise capacity, and left ventricular morphology and function.

Results—There were 14 men and 6 women, mean age 64.3 years. Years from symptom onset varied from 2.1 to 3.2. Dyspnoea was the most common limiting symptom. Thirty per cent of the patients were classified as NYHA IIIB. Physical capacity was reduced to 79% of the expected. Left ventricular hypertrophy was present in 14/20 patients. Left ventricular systolic function was reduced with mean ejection fraction of 0.46. Diastolic dysfunction (E/A ratio <1) was present in 12 patients.

Conclusion—Many patients accepted for aortic valve replacement due to aortic stenosis show advanced disease and are referred for surgery later in the disease process than is recommended in the current guidelines.     

Liver drug metabolism in patients undergoing open-heart surgery

The effect of open-heart surgery on the drug metabolism of the liver was investigated in 17 patients by using the rate of antipyrine elimination as an index. A correlation was found between the pre-operative heart size and the antipyrine elimination rate. In patients with a markedly dilated heart, the plasma antipyrine half-life was prolonged and apparent clearance significantly impaired. Immediately postoperatively, antipyrine elimination was impaired in all patients. Later, the drug metabolism improved in patients with atrial septal defect, changed temporarily in patients with aortic valve replacement, and remained unchanged in patients with mitral valve replacement. The results indicate that adaptive changes in drug metabolizing capacity occur in patients undergoing cardiac surgery. The changes are related to the type of lesion corrected, the pre-operative functional capacity of the liver, and the time lapse after surgery.     

Early experience with left ventricular volume reduction surgery in Syria

OBJECTIVE: To review our early experience with left ventricular volume reduction surgery (the Batista operation) in the management of patients with end-stage heart failure. METHODS: Between December 1996 and April 1998, 10 patients (9 males, mean age 32yr) with advanced symptomatic cardiomyopathy underwent left ventricular volume reduction surgery at Damascus University Cardiovascular Surgical Center. The cause of cardiomyopathy was idiopathic in three patients, valvular in four, ischemic in two, and viral myocarditis in one patient. Concomitant procedures included aortic valve replacement in four patients, mitral valve repair in six patients, and coronary artery bypass grafting in two patients. RESULTS: All patients survived the procedure. Echocardiography prior to discharge documented significant improvement in ejection fraction in all but two patients. Mean follow-up was 7.6 months. After discharge, three patients developed progressive congestive heart failure to which they subsequently succumbed, and two more patients died suddenly late postoperatively. Only two patients continue to show both clinical and echocardiographic evidence of improvement. CONCLUSION: Left ventricular volume reduction surgery cannot be freely advocated until better means are found to identify patients who will benefit from the procedure, and proper prophylaxis against fatal postoperative complications can be afforded.     

Effects of cardioplegic solution on human contractile element velocity.

A technique for measuring the maximum contractile element velocity (Vpm) of the myocardium was developed, verified, and employed in patients to allow accurate intraoperative assessment of the adequacy of myocardial protection. Four groups of patients were studied. Ten patients had coronary artery bypass grafts (CABG) with cardioplegia; 13 had CABG with coronary perfusion, ventricular fibrillation at 28 degrees C, and aortic clamping for distal anastamoses; 6 had aortic valve replacement (AVR) with cardioplegia; and 7 had AVR with coronary perfusion to the beating heart. For cardioplegia, a solution of 5% dextrose in 0.2% saline at 4 degrees C with 25 mEq of potassium chloride and 12.5 gm of mannitol was infused initially, followed by 500 ml every 30 minutes. Clinically all patients did well, and there were no deaths. Patients having CABG with intermittent coronary perfusion during ventricular fibrillation had significant (p less than 0.01) depression of Vpm from 38.3 to 30.8 sec-1 while Vpm in patients having CABG with cardioplegia was unchanged. Patients having AVR with continuous coronary perfusion or with cardioplegia (average anoxia time, 70.4 minutes) had no significant change in Vpm. We conclude that this cardioplegic solution provided adequate protection of myocardial function for up to 105 minutes of continuous aortic clamping in humans. The depression in Vpm observed following CABG with intermittent coronary perfusion is consistent with previous suggestions that this combination is detrimental because of maldistribution of coronary blood flow during ventricular fibrillation.     

Clinical study on the use of retrograde cardioplegia with St. Thomas' Hospital solution

One hundred and three consecutive patients with aortic valve disease and twenty seven patients with ischemic heart disease of severe critical coronary stenosis or left main trunk stenosis underwent open heart operations with the use of retrograde cardioplegic technique for myocardial protection. Under complete cardiopulmonary bypass, a balloon catheter was inserted into the coronary sinus through small right atriotomy and secured in place. Retrograde cardioplegia was accomplished using cold St. Thomas' Hospital solution by drip method at height of 60 to 80 cm with topical saline slush. Cardiac resuscitation was very easy and acceptable hemodynamics were obtained in all patients. Even in 8 patients in which aortic crossclamping time was above 180 minutes cardiac recovery was excellent except one who needed IABP support. Eight patients in aortotomy group were died postoperatively from the reasons unrelated to myocardial protection. Postoperative hemodynamic data and enzymatic analyses of CK-MB revealed good myocardial protective effects. Retrograde cardioplegia with the use of cold St. Thomas' Hospital solution is thus an effective alternative of myocardial protection in aortic valve surgery or aortotomy surgery and in coronary revascularization for multiple coronary stenoses or left main trunk lesions.     

Heart surgery with extracorporeal circulation leads to platelet activation at the time of hospital discharge

Objective: Heart surgery with extracorporeal circulation has a marked effect on platelet function and coagulation accounting for abnormal blood loss and allegedly a low incidence of thromboembolic complications. Little is known about platelet function at the time of hospital discharge of routine patients. Methods: Blood samples from 91 patients undergoing elective heart surgery were drawn before surgery and prior to discharge. Thirty-seven patients underwent coronary artery surgery and 54 an aortic valve implantation. The mean age of patients was 69±9 years. Fifty patients were male and 41 female. Platelet function was evaluated using plasma β-thromboglobulin quantification in enzyme-linked immunosorbent assay. In addition, flow cytometric analysis of platelet–monocyte conjugates and platelet–neutrophil conjugates was performed. Results: The platelet count before discharge was significantly increased (265±86 vs. 212±61×10⁹/l preoperatively). β-Thromboglobulin was significantly increased (176±127 vs. 79±70 ng/ml preoperatively) and flow cytometry proved a significant increase in monocyte–platelet aggregates (8.3±5.4% vs. 5.3±2.6% preoperatively) indicating platelet activation at the time of hospital discharge. There were no significant differences among the three subgroups coronary surgery, mechanical valve insertion and biological valve insertion. Conclusions: Heart surgery with extracorporeal circulation leads to significant platelet activation and a reactive increase in platelet count before discharge. This is in contrast to the reduced platelet function immediately postoperatively.     

Left coronary ostial stenosis caused by syphilitic aortitis

We report 2 cases of cardiovascular disease related to end-stage syphilitic infection, which is now relatively rare. A 49-year-old man (case 1), and a 45-year-old man (case 2) were admitted to our hospital for angina pectoris. Cardiac catheterization showed severe aortic regurgitation and left coronary ostial stenosis. Active syphilis was detected in both cases by routine blood examination on admission. Oral ampicillin was started immediately to treat the syphilis; however, during the course of treatment, acute heart failure developed in both patients. We performed emergency aortic valve replacement and coronary artery bypass grafting. Intraoperatively, the orifice of the left coronary artery was almost occluded, and retrograde perfusion of cardioplegia was needed to induce cardiac arrest. Both patients recovered uneventfully. When treating patients with antibiotics for syphilitic disease, it is important to prepare for the possibility of urgent surgery.