Coronary artery bypass in patients over 70 years of age: indications and results.

With recent advances in all phases of coronary care and the increasing success of coronary arterial surgery, operative treatment of coronary artery disease is more readily recommended, even for patients over 70 years of age. In a series of 3,730 patients who underwent aortocoronary bypass from November 1969 through June 1974, there were 95 patients who were 70 years of age or older. The primary indication for surgery was severe angina, which was present in 88 patients. The mean coronary arterial score was 9.51. Associated valvular lesions were treated surgically in 21 patients, and a left ventricular aneurysm was resected in 7. Improvements in surgical technique and postoperative care are responsible for the hospital mortality rate of only 4.8 percent in the 21 patients operated upon during the first 6 months of 1974 compared with the overall mortality rate of 22.1 percent in all 95 patients. Long-term follow-up among the 95 patients includes data from 33 patients: 9 patients whose condition improved, 21 who were asymptomatic and 1 "coronary death".

The morphology of ascending aortic aneurysms.

To determine the frequency of morphologic abnormalities of the aorta, especially of the media, in patients with aneurysms of the ascending aorta, tissue specimens from surgically resected ascending aortic aneurysms of 339 patients were studied. Included were 232 men and 107 women; 53 (29 men, 23 women) had clinical signs of Marfan's disease. Features evaluated and graded included fragmentation of elastic fibers, cystic medial change, medial fibrosis, medial necrosis, atherosclerosis, periaortic fibrosis, and thickening of the vasa vasorum. Both elastic fragmentation and cystic medial change were present in a high percentage of patients. Cystic medial change was inversely correlated with increasing age of patients, especially in the group of patients without clinical evidence of Marfan's syndrome. Marked changes of these types in many younger patients without Marfan's syndrome could reflect a "tissue insufficiency" in early life that causes the aortic wall to weaken and dilate. Medial necrosis, fibrosis, and atherosclerosis were directly correlated with age. Hemodynamic events are considered to initiate injury and repair within the aortic wall. Dissection was more frequently seen with medial abnormalities than with atherosclerosis.

Interruption of the aortic arch. Surgical considerations.

During a 10 year period, January, 1965, through January, 1975, 5 patients with interruption of the aortic arch (IAA) underwent operation at the Texas Heart Institute. The mortality rate was 60 per cent; 2 patients survived the operation. One 11-day-old infant with IAA, type A, a ventricular septal defect (VSD), and a patent ductus arteriosus (PDA) underwent successful two-stage treatment. A left subclavian-ductus anastomosis, closure of the PDA, and banding of the pulmonary artery were done initially. The VSD was closed later. The second survivor, a 3-year-old girl, had IAA, type B, with a PDA and VSD. Total correction was done with the aid of cardiopulmonary bypass and hypothermia. Considerations include palliative and staged procedures versus total correction with either conventional cardiopulmonary bypass or deep hypothermia and circulatory arrest. Survival rate is improved if associated lesions are totally repaired or palliated at the time of reconstruction of IAA.

Complications of cloth-covered prosthetic valves: results with a new mitral prosthesis.

During a 12 year period 5,103 cardiac prosthetic valves in 4,193 patients have been evaluated for performance and incidence of complications. As a result of our experience, the advantages of fewer embolic phenomena, associated with epithelialization in completely cloth-covered valves and those with cloth-covered seating rings, are outweighed by the problems of cloth wear, hemolysis, and hemodynamic obstruction from tissue overgrowth. A valve has been designed which incorporates the desirable features of full-flow orifice, low-profile, self-washing principle, polished contact surfaces, durable materials, and a large eccentric sewing ring into a new mitral prosthesis. Clinical evaluation in 394 patients from Aug. 1, 1971, through Dec. 31, 1973, has demonstrated excellent hemodynamic function and a low incidence of thromboembolic phenomenon.

Intracardiac repair of tetralogy of Fallot. Five-year review of 403 patients.

During the 5 year period 1969 to 1973, 403 patients underwent intracardiac repair of tetralogy of Fallot. The patients ranged in age from 3 months to 41 years. Before operation, 86 per cent were cyanotic and 14 per cent were acyanotic. Forty-nine per cent had had at least one palliative procedure before total correction. Mahor associated anomalies included atrial septal defect in 24 per cent, patent ductus arteriosus in 2.5 per cent, coronary anomalies in 4 per cent, and left superior vena cava in 4.5 per cent. Seven per cent of the patients had pulmonary atresia. Pulmonary valvotomy was performed in 111 patients and complete excision of the pulmonary valve in 151. Patch graft reconstruction of the right ventricular outflow tract was performed in 57 per cent of the patients. In 11 patients a conduit was used to connect the right ventricle to the pulmonary artery. The over-all hospital mortality rate was 9.5 per cent, with the lowest rate (3.5 per cent) in the age group 6 to 10 years and the highest in the infant and adult groups (16.5 and 14.5 per cent, respectively). Three known late deaths occurred. A residual ventricular septal defect (VSD) was found in 3 per cent of the patients and an aneurysm of the pericardial patch in the right ventricular outflow tract developed in 7 patients. Intracardiac repair of the tetralogy of Fallot can be performed with reasonable risk and low morbidity. In our experience the optimal age for elective surgery is between 6 and 10 years.

Treatment of severe coronary artery disease with quadruple and quintuple saphenous vein grafts. Review of 100 consecutive patients.

In order to establish the anatomic criteria, the functional results, and the safety of complete myocardial revascularization for severe coronary artery disease, 100 consecutive patients who received four or five saphenous-vein grafts were analyzed. Ages ranged from 37 to 75 years (mean, 56 years). Men predominated by a ratio of 12:1. As an indication of the severity of multiple-vessel disease, 28 percent were in functional class 4, and left ventricular function was classified as good in 47 percent, as fair in 44 percent, and as poor in 8 percent. Coronary arterial scores ranged from 9 to 15 (average, 12.2). Fourteen patients had significant left main coronary arterial obstruction. All 100 patients had grafts to the left anterior descending coronary artery; 96 to the right coronary artery; 94 to the obtuse marginal branch of the circumflex; 78 to a diagonal branch of the left anterior descending; and 27 to the distal circumflex. Operative mortality was 5 percent. Nonfatal perioperative myocardial infarction occurred in 10 percent, and only one of these had low cardiac output. Follow-up from 5 to 23 months showed 95 percent of the patients to be improved, with 70 percent free of angina. Two late deaths occurred, for an overall mortality of 7 percent.

Aortocoronary artery bypass: present indications and risk factors.

From 1969 through 1974, a total of 4,522 patients were operated on for coronary artery occlusive disease. This article is an in-depth analysis of a consecutive series of 275 of these patients, operated on during 1974. The mortality was 1.8% and perioperative myocardial infarction occurred in 3.6%. On analysis of risk factors, it was found that 24% of the patients were over the age of 60; 57% had some degree of left ventricular dysfunction; 9% had generalized hypokinesis; 24% were New York Heart Association functional class IV; 13% had left main coronary artery stenosis; and 11% had preinfarction angina. On analysis of the early mortality, the limiting factor was diffuse coronary arteriosclerosis combined with poor ventricular function. This resulted in inadequate or incomplete myocardial revascularization. Since these two risk factors are usually predictable, coronary artery bypass can be recommended not only for patients with intractable angina, but also for patients with impaired left ventricular function associated with angina, and in patients without angina who have a positive stress electrocardiogram.

Dissecting aneurysm of the descending aorta. Improved surgical results in 91 patients.

Dissecting aneurysm of the descending thoraic aorta (type iii) is a specific disease process whose pathogenesis, pathologic description, surgical treatment, and prognosis is different from dissections of the ascending arota (types l and ll). From 1964 through 1974, 91 patients underwent surgical correction of type iii dissection. The operative mortality was 21% and late mortality, up to ten years follow-up, was 13%. During the past four years, operative mortality has dropped to 6.5%. Mortality was determined by extent of the aneurysm and underlying cardiac disease. Antihypertensive and negative ionotropic drugs have not been used as definitive treatment but as adjuncts in perioperative support. Based on our present mortality of 6.5%, with no late mortality, we urge early surgical treatment of acute and chronic dissecting aneurysms of the descending thoracic aorta before extension, rupture, or massive enlargement of the aneurysm occurs.

Long-term survival following coronary artery bypass. Analysis of 4,522 consecutive patients.

A consecutive series of 4,522 patients who received aortocoronary bypass (ACB) from October 1969 through December 1974 has been analyzed with respect to cumulative (actuarial) survival, cause of late death, and late postoperative complications. Through December 1973, 2,676 patients received ACB alone. Cumulative survival was 85.9% for five years. Late cumulative mortality averaged 2.7% per year. Causes of death were myocardial in origin in only 60.4% of the patients. Late complications of nonfatal myocardial infarction occurred in 4.1% of the patients, and congestive heart failure occurred in 10.2%. However, preoperative congestive heart failure was present in 25% of these subjects. Mortality in 1974 was 3.4% in patients who underwent ACB only, and 4.2% for all patients who received ACB procedures (1,478 patients). Comparison to previous medical data makes it appear that this surgery increased the actuarial survival over long-term follow-up.

Aneurysm and fistula of the sinus of Valsalva. Clinical considerations and surgical treatment in 45 patients.

Aneurysms and fistulas of the sinus of Valsalva, although rare, present a challenging surgical problem. Forty-five patients with this lesion have undergone operative treatment during the last 17 years. The series includes 32 male and 13 female patients ranging in age from 2 to 68 years with a mean age of 35.3 years. Only 1 early death occurred in the series, a hospital mortality of 2.2%. Diagnosis of the aneurysm was made preoperatively in 30 patients and discovered at operation 15. The lesion involved the right coronary sinus in 28 patients, the noncoronary sinus in 19, and the left coronary sinus in 5. The aneurysm had not ruptured in 22 patients and had formed a fistulous communication between the right coronary sinus and the right ventricle in 13. Acute rupture occurred in 10 patients (22.2%). Long-term follow-up data were obtained in 38 patients after 1 to 15 years. Late mortality is low. A nonruptured aneurysm of the sinus of Valsalva should be managed conservatively when it occurs as an isolated lesion. Our experience supports the concept that perforated aneurysms and fistulas of the sinus of Valsalva, even if asymptomatic, should be treated operatively.

Ascending aorta-abdominal aorta bypass: indications, technique, and report of 12 patients.

Use of the supraceliac segment of the abdominal aorta for ascending aorta-abdominal aorta bypass (AAAAB) offers a new technique for management of certain difficult surgical problems. Since 1973, we have performed AAAAB in 12 patients: 4 with recurrent coarctation of the thoracic aorta; 4 with coarctation of the thoracic aorta and associated cardiac lesions requiring a concomitant intracardiac procedure; 2 with recurrent aortoiliac occlusive disease (AIOD); 1 with interruption of the aortic arch requiring concomitant pulmonary artery banding; and 1 with coarctation of the abdominal aorta. In 3 of these patients (2 with recurrent AIOD and 1 with coarctation of the abdominal aorta) the distal anastomosis was made to the distal abdominal aorta or femoral arteries. Ten patients (83.3%) experienced satisfactory results; 2 patients (16.6%) died. The technique of AAAAB provides a practical solution to complex situations in which previous procedures preclude a standard operative approach, or when necessary concomitant procedures would otherwise require a two-stage operation.

Total anomalous pulmonary venous return. Review of 125 patients treated surgically.

One hundred twenty-five patients undergoing surgical correction of total anomalous pulmonary venous return were studied. The overall mortality was 37% and was related to age at the time operation was required. Mortality was 57% during the first year of life, 29% in patients between 13 and 24 months, and 15% in those between 2 and 10 years; no deaths occurred in those over 10 years. Mortality was highest in patients with infracardiac lesions (62%), and lowest in those with cardiac defects (30%). The major cause of death was pulmonary edema, and survival was closely related to the degree of increased pulmonary vascular resistance. Surgical treatment should be delayed until at least 6 months of age, but the development of congestive heart failure may necessitate earlier operation.

Sinus venosus atrial septal defect: early and late results following closure in 109 patients.

The clinical course of 109 patients who underwent closure of a sinus venosus atrial septal defect is reviewed, with emphasis on the incidence, type, and severity of arrhythmias before and after operation. There were no operative deaths and only 1 late death. No instances of obstruction of the superior vena cava were detected clinically. One patient had a probable hemorrhagic pulmonary infarction that cleared; another may have a persistent left-to-right shunt. Excellent results were achieved in 72% of the patients, good results in 5%, and poor results in 3%. The type of arrhythmia, both before and after operation, varied with the age of the patient: younger patients had bradyarrhythmias, and older patients had tachyarrhythmias. Ten patients experienced persistent new arrhythmias postoperatively, but none were disabled, required a pacemaker, or died. The arrhythmias in all severely symptomatic patients were supraventricular tachycardias that had occurred before operation. Although functional classification after operation was clearly related to age at the time of the procedure (with younger patients having the best functional results), 19 of 21 patients over age 40 were noticeably improved after surgical closure of the sinus venosus atrial septal defect.

Early and late results after surgical treatment of preinfarction angina.

Among 3,707 patients who underwent aortocoronary bypass, 302 had preinfarction angina. Coronary angiography revealed single-vessel disease in 43 patients, double-vessel disease in 81, and triple in 178 patients. Plane ventriculography showed contractility to be normal in 178 patients, fair in 88, and poor in 36 patients. Left ventricular end-diastolic pressure was normal in 203 patients, 13 to 23 mm Hg in 73, and larger than or equal to 24 mm Hg in 26 patients. Using cardiopulmonary bypass and moderate hypothermia, single coronary bypass was performed in 45 patients, double bypass in 120 patients, triple in 118 patients, quadruple in 15, and quintuple in 4 patients. Right coronary artery endarterectomy was necessary in 22 patients. The early mortality was 6.6% (20 patients) and was strongly related to poor contractility and congestive heart failure. One- to four-year follow-up data were obtained in 126 patients. Late myocardial infarction occurred in 11 patients and caused 4 late deaths; 3 unrelated deaths occurred. Ten patients experienced no benefit from their operations, 56 are completely asymptomatic, and 53 are significantly improved. Our results show that surgical intervention can improve the poor prognosis of preinfarction angina and appears to be superior to medical treatment.

Mitral valve replacement for idiopathic hypertrophic subaortic stenosis. Results in 27 patients.

Treatment of idiopathic hypertrophic subaortic stenosis (IHSS) remains a controversial problem and depending upon many factors, medical or surgical treatment may be elected. When medical therapy fails and surgery is recommended, choice of an appropriate surgical technique may be difficult. An analysis is given of 27 patients who have undergone only mitral valve replacement as definitive treatment. Twenty-six patients were dismissed from the hospital with good or excellent results and one died (3.7 percent mortality). Pressure gradients across the left ventricular outflow tract after operation were eliminated in every instance. The mean preoperative gradient was 74 mm Hg and postoperatively was 6.9 mm Hg. Advantages and disadvantages of mitral valve replacement as definitive treatment of IHSS are presented. This method of treatment should be reserved for patients with incapacitating symptoms, congestive heart failure, severe left ventricular hypertension, unusual electrocardiographic findings or in patients who have failed to respond favorably to previous septectomy.

The value of moderate hypothermia during anoxic cardiac arrest for coronary artery surgery.

Anoxic cardiac arrest, as opposed to induced ventricular fibrillation, greatly facilitates accurate distal anastomosis in aortocoronary bypass surgery. In order to diminish the anoxic insult, general and topical hypothermia may be used. In an attempt to establish the value of moderate hypothermia during anoxic cardiac arrest two groups of patients were compared. In group I coronary artery bypass procedures were performed under normothermic conditions with anoxic cardiac arrest. Patients in group II underwent similar procedures but under hypothermic conditions. General body hypothermia to an esophageal temperature of 30 degrees C and topical hypothermia with iced saline lavage were used. Using these techniques, the average intramyocardial temperature was 26 degrees C. Nonfatal cardiac complications did not occur more frequently in the hypothermic group. Operative mortality was decreased from 6.3% in the normothermic group to 1.5% in the hypothermic group. However, in group II, in addition to hypothermia, a second factor in the reduction of mortality was the completeness of the revascularization procedure: 58.5% of the patients had three or more bypass grafts in the hypothermic group. The mean anoxic arrest time was over 50 min for all patients--those who survived as well as those who died with postoperative low cardiac output or myocardial infarction. Therefore, anoxic arrest time should be kept as short as possible and certainly less than 50 min. Intermittent aortic occlusion and performance of the proximal anastomoses using a partial occluding clamp on the aorta are currently being used and, together with moderate hypothermia, provide a further reduction in postoperative myocardial complications.