Early and late results of coronary bypass surgery. Evolution and the influence of cardioplegia.

Comparison of 1085 patients having coronary bypass surgery without cardioplegia from Jan. 1970 to Aug. 8, 1977 with 1060 patients operated upon with cardioplegia from Aug. 9, 1977 to Dec. 31, 1980 suggests that improved myocardial protection afforded by cardioplegia combined with profound topical hypothermia has its principal impact in those patients requiring urgent or emergency operations by reducing the probability of intraoperative left ventricular failure after coronary bypass. The need for postoperative balloon pumping and the risk of intraoperative death were significantly lower in patients operated upon with hypothermia + cardioplegia myocardial protection. In patients who survived 30 days after operation there was no significant improvement in long-term survival, incidence of myocardial infarction, or recurrence of angina pectoris in the cardioplegia group despite a greater average number of grafts per patient and a smaller number of ungrafted but obstructed coronary arteries.

Antibiotic prophylaxis for cardiovascular surgery. Efficacy with coronary artery bypass.

Two hundred twenty patients were randomly assigned to receive either ceforanide or cephalothin as perioperative antibiotic prophylaxis during cardiovascular surgery. More infections were seen among cephalothin recipients (8 deep, 32 total) than among ceforanide recipients (1 deep, 17 total). Among patients who had only coronary artery bypass grafting, more cephalothin recipients had infection than did ceforanide recipients (19 of 82 as opposed to 7 of 83; p = 0.001; relative risk, 2.7; 95% confidence interval, 1.22 to 6.18). The difference between the two regimens was attributable to fewer blood, wound, and urinary tract infections. Among patients who had other procedures, there was no difference in the efficacy of the two regimens. Cephalothin recipients who developed wound or blood stream infections had lower antibiotic levels in their atrial appendages than recipients not developing such infections (p = 0.02). If one assumes that cephalothin does not increase the risk of infection, then these data show that antibiotic prophylaxis prevents infection after coronary artery bypass surgery, and, in the dosages used, that ceforanide is superior to cephalothin.

Surgical correction of anomalous left coronary artery from the anterior sinus of valsalva.

Origination of the left main coronary artery from the anterior sinus of Valsalva is a rare congenital anomaly that has been associated with sudden death. Anatomical correction of this defect has only rarely been performed by unroofing the intramural segment of the proximal coronary artery or by widening the narrowed angulated origin of this anomalous vessel. This report describes the clinical course of a 33-year-old woman with this anomaly who experienced episodes of chest tightness associated with ischemic electrocardiographic changes. Surgical correction was performed by enlarging the ostium of the anomalous artery with a "sphincteroplasty" technique. Thallium scanning, which was positive prior to surgery, was normal postoperatively. The patient remains asymptomatic 6 months after surgical correction.

The reliability of angiography in predicting quality and caliber of the distal coronary artery lumen in preparation for bypass surgery.

To determine whether coronary arteriograms accurately predict the presence of distal coronary lumena that are inadequate for bypass because of diffuse disease and/or small caliber, angiographic grading of distal lumen (DL) caliber was carried out on 867 diseased coronary arteries on which bypass was subsequently attempted. Where the DL was graded as normal, bypasses could be successfully constructed in 96% of cases. Where the general DL caliber was normal but one or more localized distal stenoses were present, bypasses could be successfully constructed in 95.6% of cases. Where the DL caliber was reduced to a mild-moderate degree angiographically, bypasses were successfully constructed in 83.6%. Where the DL had a severely reduced caliber or could not be visualized at all, bypasses were successfully constructed in 73.0%. Thus, even when a severely narrowed or totally occluded DL appears present, bypass can still be performed in almost 75% of cases. The angiographic diagnosis of a nongraftable distal segment is therefore unreliable and patients should not be denied bypass on this basis alone.

Determinants of operative survival following combined mitral valve replacement and coronary revascularization.

To determine the operative survival rate following combined mitral valve replacement (MVR) and coronary artery bypass graft (CABG) operation, we evaluated 100 patients, who were seen consecutively at the Peter Bent Brigham and Brigham and Women's Hospital from 1972 to 1982. There were 63 men and 37 women; the mean age was 62 years. Thirty-six patients were in New York Heart Association (NYHA) Functional Class III, and 64 were in functional Class IV. Mitral regurgitation was predominant in 76 patients; mitral stenosis, in 24. Emergency operations were performed in 15 patients, and elective or semielective operations were performed in 85. There were 18 operative deaths (18%): 9 in patients having elective operations (10.5%) and 9 in those having emergency operations (60%; p less than 0.01). Significant preoperative factors related to operative death were NYHA functional class, increased pulmonary vascular resistance, lower cardiac index, and lower ejection fraction in the nonsurvivors. The rate of survival did not differ according to sex, age, or degree of coronary artery disease. In addition, myocardial protection with potassium cardioplegia and complete coronary revascularization significantly reduced operative mortality in the elective group of patients but did not alter the mortality in the emergency group.

The in-hospital risk of rereplacement of dysfunctional mitral and aortic valves.

From January 1, 1972, to January 1, 1981, 1282 consecutive valve replacements were performed at the Peter Bent Brigham Hospital. Fifty-eight of these (4.5%) were rereplacements: 14 for prosthetic valve subacute bacterial endocarditis (SBE), 29 for primary valve dysfunction (PVD) and 15 for perivalvular leak (PVL). Aortic rereplacement was done in 27 patients (eight for SBE, 10 for PVD and nine for PVL) and mitral rereplacement in 31 patients (six for SBE, 19 for PVD and six for PVL). Twenty-six patients were in New York Heart Association functional class III and 32 were in class IV. Ten class IV patients underwent emergency valve replacement (three for SBE, two for PVD and five for PVL). The overall in-hospital mortality rate for valve rereplacement was 14% (eight of 58 patients). For mitral valve rereplacement it was 13% (four of 31), compared with 6.4% (19 of 295) for initial mitral valve replacement. For aortic valve rereplacement, the mortality rate was 15% (four of 27), compared with 5.2% (23 of 440) for initial aortic valve replacement. The cause of death was low cardiac output in six patients, hemorrhage in one patient and sepsis in one patient. All of the patients who died were in functional class IV (p = 0.018). The in-hospital risk for rereplacement of a dysfunctional aortic or mitral valve is no different from that for primary valve replacement unless the patient deteriorates to class IV and requires an emergent operation.

Clinical staging and the tendency of malignant pleural mesotheliomas to remain localized.

Thirty-two patients who had been treated for diffuse, malignant pleural mesotheliomas were retrospectively staged according to the system of Butchart. Nineteen of the 26 patients who were seen with disease confined to one hemithorax have died. Twelve patients died without progression to a higher clinical stage, and only 1 patient died of systemic metastases. Nineteen of the 32 patients died of local tumor invasion. Regimens containing Adriamycin (doxorubicin hydrochloride) appeared to prolong the survival of patients with epithelial-type tumors. Combination chemotherapy, designed to treat soft-tissue sarcomas, produced partial responses in a small number of patients.

Pathologic findings in postcardiotomy patients managed with a temporary left ventricular assist pump.

Twenty-one postcardiotomy patients in cardiogenic shock, nonresponsive to pressors and intraaortic balloon, received temporary support with a pneumatically driven left ventricular assist pump, according to a strict National Institutes of Health protocol. Nine patients showed hemodynamic improvement after 91 to 190 hours; at least several of these patients had significant perioperative myocardial necrosis. Three patients remain well 39, 38 and 33 months after resuscitation. Eight of the patients died from hemorrhagic diathesis related to extended cardiopulmonary bypass times before hemodynamic improvement on left ventricular assist pump could be demonstrated. Correlation of myocardial biopsies taken at pump implantation in 15 patients and autopsy findings in nonsurvivors suggest that myocardial dysfunction has a reversible component that is related either to diminished compliance (probably due to edema) or to severe but reversible ischemic myocardial injury, or both. There was no evidence of thrombo- or biomaterials emboli or other pump-related complications.

The effect of low-dose aspirin and dipyridamole upon atherosclerosis in the rabbit.

To examine the effect of antiplatelet therapy upon atherosclerosis in an animal model, aspirin and dipyridamole were administered to female New Zealand rabbits while they were fed a 2% cholesterol diet. Four experimental groups of 15 animals were established: Group I (Control), no medication; Group II, aspirin, 40 mg orally five days a week; Group III, dipyridamole, 25 mg orally five days a week; Group IV, aspirin and dipyridamole. After seven weeks, the animals were sacrificed and their aortas were removed and stained. Group means of the percentage of total aortic lumenal surface occupied by gross atheromata were calculated and statistically compared with the control group mean: Group I - 49%, Group II 36%, p = NS, Group III - 47%, Group IV - 25%, p less than .01. Histologic sections of each aorta confirmed the stained areas to be atheromata of varying complexity. The lesions in animals treated with dipyridamole alone exhibited a distinct increase in smooth muscle cell proliferation. For animals receiving a combination of aspirin and dipyridamole the lesions were smaller and less advanced than those in the control group. These findings indicate that experimental atherosclerosis in rabbits is modified by the administration of anti-platelet agents and that atheroma formation is significantly inhibited when aspirin and dipyridamole are given in combination.

Emergency coronary revascularization.

Emergency operations for restoration of coronary artery blood flow are an effective means for treatment of unstable anginal syndromes. The risk of such operations is minimized by preoperative stabilization with medical therapy. Mechanical circulatory assistance may be a useful adjunct in some patients, especially in the presence of left main coronary obstruction. Utilization of emergency revascularization for patients with evolving myocardial infarction may be beneficial in some patients, but this approach remains controversial at present. Emergency revascularization for cardiogenic shock improves chances for survival in selected patients, and it may be combined with valve replacement, infarct resection, or repair of ruptured myocardium in patients with adequate residual contractile tissue.

Pseudopseudotumor of the lung. Hepatic herniation into the right major fissure imitating a pseudotumor on chest roentgenogram.

A young man presented to us with an asymptomatic ovoid mass which appeared to be in the right major fissure. The roentgenographic appearance of the lesion was that of a pseudotumor. The computerized tomography scan suggested tissue density leading to exploration. At surgery, we found the mass to be a portion of liver herniated through a diaphragmatic defect. Thus, we add type 2 hepatic herniation to congestive heart failure, empyema, hemothorax, postinflammatory "fibromas" and malignancies as a cause of interlobar pleural densities.

Salvage of acutely ischemic myocardium by emergency coronary artery bypass grafting.

After cardiac catheterization a 53-year old patient developed widespread myocardial ischemia that produced electromechanical dissociation and cardiogenic shock. The administration of methylprednisolone, the initiation of cardiopulmonary bypass and hypothermia within 40 min of the onset of ischemia, and reperfusion within 90 min of the onset of ischemia were sufficient to salvage a major portion of the ischemic myocardium.

Long-term follow-up of the Hancock bioprosthetic heart valve: a 6-year review.

Clinical experience with the Hancock porcine bioprosthetic heart valve was reviewed in 467 patients (254 men and 213 women, 18--84 years old, average, 56 years) who received 528 valves from January, 1972, to January, 1978. Associated procedures, including coronary bypass graft, ascending aortic aneurysm, and valvuloplasty were done in 102 of the 467 patients (22%). The overall operative mortality was 25/467 (5.6%), 12/226 (5.3%) for aortic valve replacement (AVR), 11/183 (6%) for mitral valve replacement (MVR), and 2/58 (3.4%) for multiple valve replacement. The first 323 patients with a minimum follow-up of 16 months (16--75 months, average 33 months) were analyzed for survival and thromboemboli. Actuarial survival at 66--75 months was 75.7% for AVR, 79% for MVR, and 75.8% for multiple valve replacement. Emboli per 100 patient-years was 0.55 for AVR (no anticoagulants), 3.9 for MVR, and 4.8 for multiple valve replacement (anticoagulants for atrial fibrillation patients only); emboli occurred only in patients with atrial fibrillation. There were seven of 528 primary dysfunctional valves (1.3%): calcification in two, tissue failure in two, and fibrosis in three. A hemodynamic study of four patients with a 21 mm Hancock Modified Orifice aortic valve prosthesis showed improved orifice areas (greater than 1.3 cm2) over the standard aortic valve. The Hancock porcine xenograft bioprosthetic heart valve has been a durable heart valve in excess of 6 years and has a low associated incidence of thromboemboli in patients off anticoagulants except in those with chronic atrial fibrillation.

Late results of operation for acute aortic dissection producing aortic insufficiency.

Since July, 1970, 8 patients with acute dissecting aneurysms of the ascending aorta producing aortic insufficiency have undergone immediate operation employing a technique in which the origin of the dissection is resected, the dissected base of the aorta is lined with nondistensible prosthetic cloth for support, and the native aortic valve is resuspended. Aortic continuity is then reestablished with end-to-end anastomosis or use of a short segment of woven graft (not necessarily circumferential). There were no operative deaths. Mean follow-up has been 60 months (range, 25 to 82 months). One late death has occurred (cerebral hemorrhage at 48 months); of the remaining 7 patients, 2 have faint murmurs of aortic insufficiency, but all are in New York Heart Association Functional Class I. This technique of aortic reconstruction in acute ascending dissections allows preservation of the native aortic valve while preventing late aortic root dilatation or major valve insufficiency.

Changing indications for the surgical treatment of unstable angina.

From 1970 to 1977, 127 patients were operated on for unstable angina. On the basis of response to intensive medical therapy, patients were classified into a medically controlled, semielective surgery group (54 patients) and a medically uncontrolled, emergent/urgent surgical group (73 patients). There were five operative deaths. 1/54 in the medically controlled group (1.8%) and 4/73 (5%) in the medically uncontrolled group; 4/5 operative deaths occured with left main coronary stenosis. There were five late deaths during a follow-up period of 12 to 84 months, 37.5 with an actuarial survival of 83.5%. If patients with unstable angina can be medically controlled, operation can be delayed and the operative long-term survival is similar to that of elective coronary bypass. Patients who cannot be controlled medically, particularly those with left main coronary lesions, should be operated on urgently with selective use of preoperative balloon support.

Insulin therapy for depressed myocardial contractility after prolonged ischemia.

Insulin was administered to two patients whose diminished myocardial contractility made it difficult to terminate cardiopulmonary bypass. In both instances, bypass was successfully terminated shortly after the insulin injection. These clinical observations led to experiments under the controlled conditions provided by the isolated, working rat heart preparation. The recovery of contractility after 30 minutes of severe ischemia was assessed in all 11 control and 11 insulin-treated hearts. Myocardial performance, as judged by the product of heart rate and peak systolic blood pressure, was significantly greater in the insulin-treated hearts. These clinical observations and experimental findings suggest the need for more extensive study of the potential value of insulin in treating depressed contractility after prolonged myocardial ischemia.