Use of dual intracoronary scintigraphy with thallium-201 and technetium-99m pyrophosphate to predict improvement in left ventricular wall motion immediately after intracoronary thrombolysis in acute myocardial infarction

Thirty-one patients with acute myocardial infarction underwent intracoronary thrombolysis. Intracoronary thallium scintigrams were obtained before and 30 to 60 minutes after thrombolysis and thallium reinjection in all patients; intracoronary technetium-99m pyrophosphate scintigraphy was performed simultaneously after thrombolysis in 16 of the 31 patients. The scintigraphic results were compared with the changes in regional ejection fraction in the area of infarction.Two patients with inferior myocardial infarction had a normal left ventricular cineangiogram with no initial significant left ventricular thallium defect. In eight patients, regional ejection fraction normalized (from 18 to 63%, p < 0.001); all eight patients showed substantial new thallium uptake after thrombolysis. In five patients, regional ejection fraction improved (from 20 to 40%, p < 0.01); three of these patients had new thallium uptake but large residual defects after thrombolysis, and two had substantial new thallium uptake but technetium-99m pyrophosphate accumulation in the area of new thallium uptake. Of nine patients with no significant change in regional ejection fraction despite thrombolysis, the initial thallium defect remained unchanged in seven. Two patients showed significant new thallium uptake with technetium-99m pyrophosphate accumulation in the same area.No changes in thallium defect size or regional ejection fraction were observed in seven patients in whom thrombolysis failed. Intracoronary injection of technetium-99m pyrophosphate after thrombolysis revealed a localized accumulation in the area of the thallium defect with or without significant thallium/technetium-99m pyrophosphate overlap, whereas in the cases of permanent coronary occlusion, no technetium-99m pyrophosphate accumulation was seen. It is concluded that combined intracoronary thallium/technetium-99m pyrophosphate scintigraphy is helpful to predict myocardial salvage and areas of irreversible damage immediately after intracoronary thrombolysis