Repeated exercise and redistribution thallium-201 scintigrams in patients with myocardial infarction treated with...

Repeat exercise thallium-201 scintigrams were performed 2 weeks, 3 months, and 6 months in 27 patients following their first myocardial infarction. All patients were treated with timolol or matching placebo, administered intravenously starting within 5 hours of onset of chest pain. The extent of transient perfusion defects in 15 timolol-treated patients increased significantly between 2 weeks and 3 months compared to a decrease in 12 placebo-treated patients (p less than 0.05). Between 3 and 6 months the extent of transient defects did not change in the two groups, and there was no difference between the groups. The extent of permanent defects was not significantly different between the timolol- and placebo-treated patients on any occasion. However, patients in the timolol group had a decrease in permanent defects with time in contrast to patients in the placebo group (p less than 0.05). Thus, early intervention with timolol in the acute phase of myocardial infarction may have consequences for the postinfarction phase, as reflected in repeat thallium-201 scintigrams.