Results of myocardial revascularization: a 12-year experience

All 740 patients who underwent isolated myocardial revascularization procedures from 1967 to 1970 at our institution were compared with the first 1000 patients who underwent similar elective operations each from 1971 to 1979. Data from these 9 years were processed through a computerized cardiovascular information registry. In the 1971-1979 period, the patients were older (median age 57 years, compared with 50 years in the 1967-1970 period), more had multivessel disease (90% vs 44%) and more had ventricular asynergy (54% vs 41%). The number of grafts per patient increased from 1.5 to 2.7, and yet morbidity declined in every category except neurologic deficit. The operative mortality rate was 1.1% from 1967 to 1979 and 1.0% from 1971 to 1979. Graft patency was determined in 475 patients from 1967 to 1970, in 533 patients from 1971, in 519 from 1972, in 540 from 1973 and in 408 from 1974. Patency rates after a mean catheterization interval of 21 months were 77%, 77%, 84%, 87% and 87%, respectively. Five- and 10-year follow-ups were completed for the 1967-1970 series and a 5-year follow-up was completed for 1971, 1972, 1973 and 1974 cohorts. The 5- and 10-year actuarial survival rates for the 1967-1970 series were 89.4% and 77.3%, respectively. The 5-year survival rates for the 1971-1974 series were 91.9%, 93.4%, 92.1% and 91.7%. Abnormal ventricular function and incomplete revascularization adversely influenced the mortality rate (p less than 0.05) in all years. The percentage of asymptomatic patients at 5 years was 66%, 65%, 69%, 67% and 74% for the five patient cohorts. Lower risk and a higher 5-year survival rate are attributable to greater technical experience, changing technology and improved management rather than to selection of lower-risk cases. These 5- and 10-year survival rates compare favorably with the reported results of medical therapy.