Predictive value of indium-111 antimyosin uptake for improvement of left ventricular wall motion after thrombolysis in acute myocardial infarction☆

Abstract In 21 patients treated with thrombolysis for acute myocardial infarction (AMI), the degree of myocardial uptake of indium-111 monoclonal antimyosin antibodies injected within 24 hours after onset of AMI was compared with the degree and extent of regional asynergy on admission and discharge, as assessed by 2-dimensional echocardiography. On the first day of AMI, 80 MBq of indium-111 antimyosin was injected and planar images were made 24 hours later. Indium-111 antimyosin uptake was evaluated for count density index (count density of infarct zone/left lung count density) in the left anterior oblique projection, in which the infarction zone was well displayed in all patients. Using 2-dimensional echocardiography, the left ventricle was divided into 13 segments and evaluated for regional asynergy, which was considered severe (akinesia or dyskinesia) or mild (hypokinesia). The extent of regional asynergy was measured by the number of asynergic segments. All 21 patients had severe regional asynergy on admission. Nine of 21 showed only mild regional asynergy on discharge and 12 of 21 had persistent severe regional asynergy in at least 1 segment. The count density index was significantly lower in patients with mild regional asynergy on discharge compared with patients with severe regional asynergy (1.63 ± 0.27 vs 2.50 ±0.42, p