Mechanisms of Technetium-99m-Pyrophosphate Accumulation in Damaged Myocardium

The purpose of this chapter is to summarize the available information concerning the pathophysiological basis for the use of the “hot spot” myocardial imaging technique, 99mTc stannous pyrophosphate in the detection of irreversibly damaged myocardial tissue, including acute myocardial infarcts. 99mTc-pyrophosphate is classified as a “hot spot” imaging technique since it concentrates in acutely infarcted myocardium. Table 3-1 identifies other “hot spot” imaging techniques that also allow the recognition of acute myocardial necrosis. This chapter will concentrate on the use of 99mTc-pyrophosphate as an “infarct avid” or “hot spot” agent to detect acute myocardial infarcts.