Fifteen year survival study of patients with obstructive coronary artery disease.

Survival rates were determined for a group of 598 patients in whom severe coronary disease was demonstrated by arteriography; initially they were treated medically and were followed-up for 15 years. Deaths due to noncoronary causes were uncommon (5% of total) in the first 5 year period but were frequent (36%) in the third period. Survival rates were 48%, 28%, 18%, and 9% for patients with single-, double-, triple-, and left main artery disease, respectively. Abnormalities documented by ventriculography were related to survival. In 386 patients who would have been candidates for bypass surgery, survival rates were 58%, 35%, 26%, and 11% for those with single-, double-, triple-, and left main artery disease, respectively. Cardiac survival curves for single-, double-, and triple-artery disease in candidates for surgery and curves constructed on the basis of 3% mortality per artery per year corresponded fairly closely. When an abnormal electrocardiogram (ECG) is considered as a single variable in multivariate analysis, 5 year survival rates of candidates for surgery were influenced by the following in order of importance: abnormal ECG, symptoms at least 5 years in duration, triple-artery disease, double-artery disease, and arteriosclerosis obliterans. A simple prognostic stratification was devised that used only ECGs and duration of symptoms for each subset based on the number of arteries affected.

Selective coronary arteriography: a clinical comparison of two contrast agents.

The radiopacity and complications of meglumine iothalamate 52% and sodium iothalamate 26% (Vascoray) were compared with those of meglumine diatrizoate 66% and sodium diatrizoate 10% (Renografin -76) in 2258 patients with and without cardiac disease. There was no difference in radiopacity and the type and incidence of adverse reactions were similar, but the frequency was significantly higher (p less than 0.05) with Vascoray in patients with constrictive pericarditis, dissecting aortic aneurysm, and primary pulmonary hypertension. The difference in the frequency of hypotension, sinus bradycardia, and transient asystole in the Renografin -76 and Vascoray groups was statistically significant. Ventricular arrhythmias occurred in 6% of the patients with primary myocardial disease compared to an average of 0.7% in those without this cardiac abnormality (p less than 0.01), but there was no significant difference in the frequency in the two contrast agent groups. All reactions were treated and the studies were performed without mortality. Results of this study show that iothalamate formulation with sodium to meglumine ratio of 1:2 containing 410 mEq/L of sodium (Vascoray) is suitable and safe for clinical use for roentgenographic studies of the heart, and coronary artery circulation.

Clinical course of patients with normal or slightly or moderately abnormal coronary arteriograms: 10-year follow-up of 521 patients.

The clinical course was followed for 10 years in 521 patients whose coronary arteriograms did not show any severe obstruction. Coronary disease had been suspected in all patients before arteriography. Two of 357 patients thought to have normal arteriograms died from coronary disease and two of 101 patients died who had less than 30% estimated narrowing of at least one coronary artery. Ten deaths ascribed to coronary disease occurred in 63 patinets who had 30-50% narrowing of at least one major coronary artery. The difference in death rates between the normal or mildly diseased groups and the group that had moderate narrowing was significant (p < 0.01). Coronary events (death from coronary disease, subsequent myocardial infarction, or arteriographic evidence of progression of coronary obstruction) occurred in 2.1% of those who had normal arteriograms, 13.8% of the group with mild lesions, and 33% of those with moderate degree of coronary arterial narrowing.

Radiation exposure to the operator performing cardiac angiography with U-arm systems.

We measured the radiation exposure received by a group of operators performing 700 coronary angiograms. All studies were performed using the brachial artery approach and the Philips Cardio Diagnost. Nineteen sites were monitored on each operator, using lithium fluoride thermoluminescent dosimeters. Four hundred examinations were performed with a table-mounted protective shield in place. Three hundred were performed without the shield. The average exposures (in mR per study) with and without the shield were 1.9/6 for the eyes and 1.4/8.3 for the thyroid. The resulting operator exposure with the shield in place is low enough so that an operator performing 25 procedures per week on a continuous basis will not exceed the recommendations of the National Commission on Radiological Protection and Units. We therefore strongly recommend the use of properly designed and appropriately positioned shield with all U-arm systems.

Natural history of obstructive coronary artery disease: ten-year study of 601 nonsurgical cases.

The most important factors in the prognosis of coronary artery disease are the number of arteries severly obstructed, significant involvement of the left main coronary artery, and generalized impairment of left ventricular function or ventricular aneurysm. Other prognostic influences at least partially independent of these factors are the severity of functional impairment imposed by angina pectoris, electrocardiographic evidence of left ventricular hypertrophy or conduction defects, hypertension, and diabetes. Candidates for bypass operation have a better prognosis than noncandidates, but difference in left ventricular function is responsible. Refinement of prognostic precision will depend largely on future improvement in measurement of obstructive disease and left ventricular function serially and better knowledge of the cause or causes of coronary artery disease.

The structural study of the saphenous vein.

From November, 1971, to September, 1974, 1,179 patients received aortocoronary saphenous vein bypass grafts at the Cleveland Clinic Hospital. Segments of saphenous vein from each patient were sent for microscopical analysis. These vein segments were classified as normal or abnormal (phlebosclerotic). Four hundred ninety-six normal vein grafts in 295 patients were restudied and had a patency of 87.9%. One hundred forty-four abnormal vein grafts in 86 patients were restudied and showed 89.5% patency. This study suggests that histopathological identification of an abnormal (phlebosclerotic) vein segment does not constitute a determining factor as far as late patency is concerned in a vein segment that is not grossly sclerotic.

Manual coronary endarterectomy. Clinical experience in 315 patients.

From July, 1970, to December, 1973, manual endarterectomies were performed on 330 coronary arteries in 315 patients. The procedures were performed on either an elective or nonelective basis. The over-all hospital mortality rate was 1.27 per cent. Postoperative myocardial infarction occurred in 4.8 per cent of these patients. Postoperative catheterization was performed on 186 endarterectomized arteries; the average time of postoperative catheterization was 13.1 months after surgery. The over-all patency rate was 76.3 per cent. This experience suggests that endarterectomy is a safe and useful adjunct to saphenous vein bypass grafting procedures when used in a restricted fashion as detailed in this presentation.

Left main coronary arterial obstruction: Long-term follow-up of 141 nonsurgical cases.

The prognosis of 141 patients with obstructive left main coronary artery disease was studied. The patients were followed up for 5 to 10 years from the date of coronary arteriography. The 5 year cardiac mortality rate was 51 percent. During the first 3 years after diagnosis, the mortality rate was especially high, 21.9, 34.7 and 43 percent, respectively. Among patients who died in the 1st year after diagnosis, evidence of left ventricular hypertrophy or conduction delay in the electrocardiogram and multiple vessel involvement indicated poor prognosis. Severe angina pectoris, evidence of congestive heart failure and generalized decrease in left ventricular contractility increased the 5 year mortality rate. More than 97 percent of the total patient population had additional lesions elsewhere in the coronary arteries.

Aorta-coronary bypass grafting with the internal mammary artery: clinical experience in 70 patients.

Clincal and angiographic results in 70 patients who received free internal mammary artery (IMA) grafts are reviewed. One postoperative death occurred, but it was not related to the free IMA technique. Forty-seven patients underwent postoperative arteriography. The average interval between operation and catheterization was 10.7 months, and the patency rate for 49 free IMA grafts was 89.8 per cent. Of the 29 patients who recieved free IMA grafts as the only revascularization procedure, 21 patients (80 per cent) progressed to Functional Class I and only 5 patients did not have improvement in their functional status.

Bridge saphenous vein graft.

Single aorta-coronary artery vein grafts (bridge grafts) were constructed to two coronary branches with a side-to-side anastomosis in 250 patients. Most of these grafts were constructed between circumflex branches (96 grafts), circumflex and diagnol branches (47 grafts), and anterior descending and diagonol branches (79 grafts). The aim of the bridge graft is to decrease the number of anastomoses, decrease the operative time, and improve graft patency. The hospital mortality rate in this group of patients was 1.2 per cent, and the incidence of postoperative myocardial infarction was 3.6 per cent. One hundred ten patients were restudied after surgery; the average time of restudy was 1 year. Ninety-two grafts of 83.6 per cent had two anastomosis patent; 6 grafts (5.4 per cent) had one anastomosis patent; and in 12 grafts (10.9 per cent), both anastomoses were occluded. One hundred twenty-six associated grafts were studied all the same time; the patency rate was 84.1 per cent. From this experience, we believe the bridge graft is a useful procedure for bypassing the small coronary artery branches.