PERSISTENT TL-201 DEFECT - CAN CLINICAL, ELECTROCARDIOGRAPHIC AND EXERCISE HEMODYNAMIC VARIABLES PREDICT DEFECT NORMALIZATION WITH REINJECTION

This study was designed to assess the contribution of clinical, electr ocardiographic and exercise hemodynamic variables to the prediction of normalization on resting reinjection scintigraphy of persistent thall ium-201 (Tl-201) myocardial perfusion defects seen with exercise and 2 - to 4-hour delayed (redistribution) imaging. To evaluate this contrib ution, we studied 159 consecutive patients with persistent Tl-201 myoc ardial perfusion defects on routine exercise and 2- to 4-hour-delayed scintigrams at the University of Rochester Medical Center who were cla ssified as having moderate or greater ischemic normalization (group 1, n = 76) or minimal to no ischemic normalization (group 2, n = 83) by reinjection scintigraphy. Multiple logistic regression analysis with b ackward elimination was used to model the effects of clinical, electro cardiographic and exercise hemodynamic data on the odds ratio of a nor malized defect. No difference was observed in the two groups with rega rd to gender, angina on exertion, rate-pressure product, exercise dura tion, resting or exertional ischemic ST changes on electrocardiogram, presence of Q waves or left ventricular hypertrophy on baseline electr ocardiogram, or total number of stress thallium defects (2.8 +/- 1.5 s egments). No single variable or combination of variables discriminated between groups 1 and 2 by logistic regression analysis. We conclude t hat defect normalization seen on resting Tl-201 myocardial perfusion s cintigraphy is prevalent in patients with persistent defects on routin e exercise and delayed myocardial perfusion scintigraphy, and was not predictable from available clinical, electrocardiographic and exercise hemodynamic variables.