Aggressive pattern of angina after successful coronary angioplasty: the role of clinical and angiographic factors

To assess possible clinical and angiographic factors associatedwith acute coronary events following PTCA, we performed quantitativeangiography in 168 consecutive patients who had undergone successfulangioplasty in a native vessel (94 for stable angina, 74 forunstable angina), and who were restudied (24±15 weeks;range 4 to 52) because of recurrent anginal symptoms. Of the168 patients, 38 (Group 1) were restudied because the patternof angina was aggressive (unstable angina in 31, myocardialinfarction in 7) and 130 because of effort-related angina (Group2). The two patient groups were well matched for extent of initialdisease but patients in Group 1 were younger (P=0•03).PTCA for unstable angina was originally performed more frequentlyin Group 1 than in Group 2 (27 of 38 patients (71%) vs 47 of130 patients (36%), P=0•0001). The overall restenosis rate(68% vs 62%) and the non-occlusive restenosis rate (45% vs 57%)were not significantly different between Groups 1 and 2. However,occlusive restenosis (total occlusion at the site of the angioplasty)occurred in 10 patients (26%) in Group 1 compared with eight(6%) in Group 2(P=0•0004). Disease progression in non-dilatedsegments occurred in nine patients (24%) in Group 1 and in 10(8%) in Group 2 (P=0•0006). Our conclusion is that patients who require re-investigationas a result of angina which has become aggressive followingPTCA are usually those who originally underwent PTCA for unstableangina. These patients have a higher incidence of occlusiverestenosis or disease progression.