MYOCARDIUM

Scintigraphy with Tc-99m pyrophosphate is commonly used to detect acute myocardial infarction. Similar findings are present with Tc-99m diphosphonates, when there is an excess of tissue calcium, following local tissue necrosis or damage. Focal uptake is seen with transmural myocardial infarction (ref) . Patchy uptake has been noted in unstable angina pectoris, and diffuse uptake has been observed with cardiomyopathies (ref) , pericardial tumors, and diffuse pericarditis. Persistent uptake following infarction correlates with a higher rate of complications and with left ventricular aneurysm. Other causes of myocardial uptake include myocardial contusion, electro-cardioversion, and amyloidosis (ref)

Ischemic cardiomyopathy.

This whole-body bone scintigram shows diffuse radionuclide uptake in the region of the heart of a patient with two previous myocardial infarctions and ischemic cardiomyopathy. The ejection fraction was 14%.

Amyloidosis

Anterior view of the whole-body bone scan show intense radiotracer uptake in the myocardium.