Follow-up technetium-99m stannous pyrophosphate myocardial scintigrams after acute myocardial infarction.

Technetium-99m stannous pyrophosphate (99mTc-PYP) myocardial scintigrams were obtained in 68 patients during acute myocardial infarction (AMI) and at follow-up 15.9 +/- 8.8 weeks later. All patients with AMI had a positive scintigram (2+ or greater); only one of 46 control patients (2%) had a positive (2+) scintigram. At follow-up scintigraphy 6 to 37 weeks following AMI, 57% of patients had a persistently positive scintigram even though recurrent AMI was suspected in only one of these patients. Patients with persistently positive scintigrams tended to have more severe disease as evidenced by compensated congested heart failure (41%) persistent angina (77%), and ECG evidence of ventricular dyssynergy (51%), We conclude that 1) in patients with prior AMI, a 2+ abnormality on 99mTc-PYP scintigram may not represent new AMI; 2) a persistently positive 99mTc- PYP scintigram may have prognostic implications since it occurs predominantly in patients with severe symptomatic coronary disease.