Exercise electrocardiography and myocardial scintigraphy in the serial evaluation of the results of percutaneous transluminal coronary angioplasty.

Abstract

The diagnostic value of exercise ECG using 14 leads and 201Tl scintigraphy were evaluated in 54 of 70 patients who underwent percutaneous transluminal coronary angioplasty (PTCA), both in the iniital assessment and serial follow-up of patients after PTCA. Of the 45 patients who had successful PTCA, 36 had complete noninvasive studies performed before and 1 mo. after PTCA. Of these 36, 33 were asymptomatic 1 mo. after PTCA; the number of patients with an abnormal exercise ECG decreased from 20 to 7 (P < 0.01), and with an abnormal 201Tl scintigram, from 21 to 6 (P < 0.001); the number of patients who had at least 1 of the 2 tests positive decreased from 26 to 10. The average treadmill time increased from 448 .+-. 183 to 618 .+-. 119 s (P < 0.001) and the average rate-pressure product increased from 19.81 .+-. 6.4 to 31.35 .+-. 4.6 U .times. 103 (P < 0.001). Of the 10 patients with a positive test, 2 had a partial restenosis .gtoreq. 50% but < 70% on the 6-mo. control angiogram; 2 had a residual stenosis .gtoreq. 50% in a vessel that was not dilated and 3 had an abnormal scintigram before and 1 mo. after PTCA that subsequently became negative at 6 mo. Six months after PTCA, a control angiogram was performed in 20 asymptomatic patients; 18 had an excellent PTCA result and 2 had a partial restenosis .gtoreq. 50% but < 70%. The stress test results were normal in patients with a successful 6-mo. PTCA and abnormal in the 2 patients with a partial restenosis. Ten patients redeveloped angina within 3 mo. of PTCA; 9 developed a restenosis .gtoreq. 60% and 1 had a 90% left circumflex stenosis that could not be dilated or grafted. Six of the 10 patients had a normal exercise EEG and scintigram at 1 mo. that became abnormal when symptoms reappeared. The rate-pressure product before PTCA and when angina symptoms recurred was similar (18.00 .+-. 2.20 vs. 23.58 .+-. 6.7 U .times. 103) (NS [not significant]). The use of clinical symptoms in conjunction with the physiologic data, ECG and myocardial scintigram acquired during exercise provide important short-term data on the angiographic evolution of PTCA results. The noninvasive tests may be useful in determining guidelines for repeat angiography in patients who have had PTCA.