Reverse redistribution on dynamic exercise and dipyridamole stress technetium-99m-MIBI myocardial SPECT

Reverse redistribution on 201TI-chloride stress-redistribution myocardial scintigraphy has been associated with coronary artery stenosis. We report a patient whose two separate 99mTc-MIBI myocardial SPECT stress studies (dynamic exercise and dipyridamole) showed septal reverse redistribution and fixed inferior defect. Echocardiograms showed left ventricular (LV) hypertrophy and diffuse hypokinesis, especially in the inferior wall, and EKG showed LV hypertrophy and strain and inferior infarct. Coronary angiogram confirmed two-vessel disease involving 80%-90% stenosis of the proximal second diagonal branch of the left anterior descending artery and 75%-90% stenosis of the right coronary artery as well as global left ventricular dysfunction. Reverse redistribution on 99mTc-MIBI myocardial SPECT occurring on dynamic or dipyridamole stress may indicate damaged but viable myocardium.