CLINICAL IMPLICATIONS OF LATE PROVEN PATENCY AFTER SUCCESSFUL CORONARY ANGIOPLASTY

Background. The introduction of percutaneous transluminal coronary angioplasty (PTCA) has changed the pattern of intervention in coronary artery disease. However, the long-term results in patients undergoing successful, elective, native-vessel PTCA are not yet fully characterized. Because the healing and subsequent proliferative response after angioplasty are time related, it was the purpose of the present study to determine the long-term outcome in patients whose dilated arteries have been demonstrated to be patent 4-12 months after successful, uncomplicated PTCA. Methods and Results. The patients were grouped on the basis of the 4-12-month catheterization into those whose vessels were angiographically "normal" or had luminal irregularities only at the PTCA sites (396 patients), those whose vessels also had luminal irregularities elsewhere with or without PTCA site luminal irregularities (680 patients), and those with significant obstructive disease (more than 50% diameter narrowing) at sites other than the PTCA sites (426 patients). Of 1,502 such patients, long-term follow-up was available in 1,491. At the time of the original angioplasty, the normal patients had a 1.8% incidence of multivessel disease; luminal irregularity patients, 9.4%; and obstructive disease patients, 58.7%. At angiographic restudy, 16.4% of the obstructive disease patients continued to have multivessel disease. The patients were followed for the events of death, myocardial infarction, coronary surgery, and repeat PTCA. The 6-year survival rate was 95%; cardiac survival, 96%; and freedom from all events, 65%. The strongest correlate of events during follow-up was the angiographic status of the undilated segments. At 6 years, freedom from cardiac events was noted in 77% of the normal group, 61% of the luminal irregularity group, and 55% of the obstructive disease group. Diabetes and hypertension were also independent correlates of events. Conclusions. Results from the present study show that associated disease in undilated segments is a strong predictor of late events in patients after successful, uncomplicated, restenosis-free PTCA. However, the need for further revascularization was frequent even in patients without obstructive disease. Completeness of revascularization is appropriate when possible, and limiting progression of coronary disease at sites remote from those dilated should improve on these late results.