Comparison of myocardial ischaemia in post-infarction patients with and without angina: Assessment by dipyridamole²⁰¹T1 imaging

Ninety patients with old myocardial infarction were studied to evaluate the efficacy of intravenous dipyridamole²⁰¹Tl imaging for the detection of myocardial ischaemia in post-infarction patients, and to compare the prevalence of ischaemia in 63 patients with post-infarction angina (group I) and 27 patients without angina (group II). Thirty-four of the patients in group I and 15 of the patients in group II received coronary arteriography (CAG) for comparison; these were labelled groups IA and IIA, respectively. On²⁰¹T1 imaging, the incidence of scar with ischaemia in the infarct zone and scar with ischaemia at a distance were 72% and 42% in all patients, 89% and 52% in group I vs 33% and 19% in group II (P<0.001 and P<0.01, respectively). On CAG testing, the rates of infarct-related recanalization vessel and multi-vessel disease were 76% and 68% in group IA vs 40% and 40% in group IIA (P<0.05 and P>0.05, respectively). Thus, dipyridamole 201T1 imaging is a useful modality and postinfarction angina a proper indicator in the detection of myocardial ischaemia in post-infarction patients.