Extracardiac accumulation of labeled red cells was noted on a gated equilibrium blood pool study. The appearance and location of radiotracer mimicked a left ventricular pseudoaneurysm. Echocardiography failed to reveal a “neck” or an extraventricular sac, and there was excellent posterolateral left ventricular wall motion. Previously obtained plain radiographs and CT images of the chest were reviewed. An elevated left hemidiaphragm associated with superior displacement of the spleen accounted for the extracardiac radiolabeled red cells.