Early and late results of coronary artery bypass after failed angioplasty. Actuarial analysis of late cardiac events and comparison with initially successful angioplasty

We reviewed the results of early (<24 hours) coronary artery bypass after unsuccessful percutaneous coronary artery angioplasty in 146 patients treated between October 1979 and July 1986. Overall operative mortality was 2.7%, and risk was significantly increased among patients with hemodynamic instability and new occlusion or further narrowing of the dilated vessel (3.8 versus 0%, p < 0.05). Actuarial analysis was used to compute the rates of cardiac events during the follow-up interval, and event rates were also estimated in a comparison group of 776 patients who had successful first-time PTCA during the same time period. At a follow-up interval of 5 years, the cumulative risks of recurrence of angina and need for an additional procedure (bypass or angioplasty) were significantly (p < 0.05) lower for patients who had undergone bypass than for those who had successful angioplasty (angina 21% versuys 56%, PTCA 2% versus 21%, CAB 6% versus 16%). Cumulative risks of myocardial infarction and death were 4% versus 9% and 6% versus 9% in the two groups. The differences between late outcomes in the bypass and angioplasty groups persisted when patients were stratified into cohorts with single-vessel and multivessel disease, and the highest late event rate occurred in patients in the angioplasty group who had incomplete revascularization. The difference in late events after bypass or angioplasty was greatest during the first year. These late data should be considered when the mode of revascularization (bypass or angioplasty) is selected for symptomatic patients, especially those with multivessel disease.