Coronary angioplasty after coronary bypass surgery: Initial results and late outcome in 422 patients

From 1978 to 1988, coronary angioplasty was performed in 422 patients with prior coronary artery bypass surgery (264 patients with native coronary artery angioplasty and 158 patients with graft angioplasty). Angioplasty was successful in 84%, unsuccessful but uncomplicated in 11% and complicated by one or more major cardiac events in 5% (myocardial infarction 5%, emergency bypass surgery 2% and death 0.2%). Follow-up data were obtained in 99% of 356 patients with successful angioplasty. At a mean of 33 ± 26 months, 92% were alive, 73% had improvement in angina and 61% were free of angina. One or more of the following late events occurred in 67 patients (19%): myocardial infarction (6%), elective reoperation (13%) and cardiac death (6%). Repeat angioplasty was performed in 27%, with a success rate of 89% and no deaths.Initial success rates were equal in native vessel versus graft angioplasty, but late outcome was less favorable with the latter because of a higher rate of infarction (11% versus 4%, p < 0.05) and need for reoperation (19% versus 10%, p < 0.05). The initial success rate was higher in vein grafts <1 year old compared with grafts 1 to 4 years or >4 years after operation (92% versus 85% versus 83%, respectively) and adverse late events were less frequent after angioplasty in recent vein grafts (<1 year 13%, 1 to 4 years 35%, >4 years 29%; <1 versus >1 year, p < 0.05).The initial angioplasty success rate was higher with distal anastomotic vein graft sites (89%) than with midshaft (86%) or proximal (80%) anastomotic sites. There was a similar trend for late restenosis (distal 40%, midshaft 46%, proximal 60%). Other predictors of restenosis included smoking (p < 0.01) and male gender (p < 0.05).Although coronary angioplasty can be performed with high initial success, low morbidity and very low mortality rates in patients with prior coronary bypass surgery, repeat angioplasty for restenosis or disease progression was necessary in 27%. After successful angioplasty, life table analysis showed an actuarial 5 year survival rate of 89% and freedom from death, infarction or repeat bypass surgery in 71%. Predictors of late death or infarction included prior infarction (p < 0.05), unstable angina (p < 0.05), multivessel disease (p < 0.05) and left ventricular ejection fraction <25% (p < 0.01)