Indium-111-Fab antimyosin antibody accumulation was studied in an 81-yr-old patient who was treated twice for
unstable angina on ECG, signs of apicoseptal
infarction, anterolateral and inferior
ischemia without clinical evidence of an acute coronary event. During the last hospitalization, 9 and 3 mo after the previous ones, additional
ischemia in the inferoposterior wall was demonstrated. Antimyosin was administered to detect acute
infarction but pump failure developed and the patient died. Autopsy confirmed all stages of
infarction on the anterior and lateral walls, predominant
fibrosis in the apicoseptal region and predominant acute
necrosis in the inferior wall. Macroscopic and scintigraphic examinations of transverse slices gave concordant results. A mixture of
infarctions and normal tissue was confirmed by histologic findings. Antimyosin antibody accumulation was seen in areas of acute
necrosis or bordering areas of reduced uptake in myocardium with remote damage, probably caused by prolonged episodes of
unstable angina without evident acute coronary event.