Prognostic value of 201Tl myocardial scintigraphy after coronary artery bypass grafting

Background Tl-201 myocardial scintigraphy (Tl-201 SPECT) is of strong prognostic value in various populations with suspected or known coronary artery disease. However, its value in patients with coronary artery bypass grafting (CABG) is not fully assessed. Methods We examined 115 consecutive patients to determine the relation between clinical data/stress Tl-201 SPECT performed 5+/-3 years after CABG, and subsequent cardiac events. Results Thirteen patients (11%) had stress-induced angina, 22 (19%) had electrical positivity, and 97 (84%) had abnormal scintigraphy, including 62 (54%) with reversible defects. During follow-up (35+/-22 months), there were nine cardiac deaths, seven myocardial infarctions, and 20 revascularization procedures. Multivariate Cox analysis identified the delay between CABG and scintigraphy (P<0.01, relative risk (RR) = 1.01), the extent of stress Tl-201 defects (P = 0.04, RR = 1.18), and increased stress Tl-201 lung uptake (P = 0.03, RR = 3.56) as significant predictors of cardiac deaths/infarctions. Delay between CABG and scintigraphy (P < 0.001, RR = 1.01), the extent of stress Tl-201 defects (P = 0.03, RR = 1.15), and that of reversible defects (P = 0.05, RR = 1.13) were the only significant predictors of total events. Conclusions Besides the delay between CABG and scintigraphy, the scintigraphic parameters were the only significant and additive predictors of cardiac events in 115 patients with CABG. ((C) 2001 Lippincott Williams & Wilkins).