An 11 Year Evolution of Coronary Arterial Surgery (1967–1978)

Abstract

All patients who underwent isolated myocardial revascularization procedures from 1967–70 (n = 741) were compared with the first 1,000 patients who received similar elective operations each year from 1971 through 1978. Data from these eight years were processed through a computerized cardiovascular information registry. Median age increased from 50 to 56 years, multiple-vessel disease increased from 44 to 89%, and left ventricular asynergy from 41 to 54%. The number of grafts per patient increased from 1.5 to 2.5 and yet morbidity declined in every category except neurologic deficit. Operative mortality was 1.1% from 1967 through 1978 and 0.9% from 1971 through 1978. Graft patency was determined for 475 patients from 1967–70, 553 patients from 1971, 519 from 1972, and 540 from 1973. Patency rates after a mean catheterization interval of 21 months were 77, 77, 84, and 87% respectively. Higher graft patency coincides with introduction of the internal mammary artery graft. Five year follow-up was completed for the 1967–1970 series and 1971, 1972, and 1973 cohorts. Actuarial five year survival was 89.6, 91.6, 93.2, and 91.7%. Five year survival comparisons between 1967–1970 patients and 1971–1973 patients in single-, double-, and triple-vessel disease categories show significant extended longevity in the later experience. Abnormal ventricular function and incomplete revascularization adversely influenced longevity (p < 0.05) in all years surveyed. In those series the percentage of asymptomatic patients at five years was 66, 65, 69, and 67%. Lower risk and higher five year survival are attributed to greater technical experience, changing technology, and improved management rather than to selection of lower risk cases.