Dipyridamole-echocardiography test: historical background and physiologic basis.

Dipyridamole was first introduced as an antianginal, coronary vasodilator agent. It was soon found that this drug could not prevent effort ischaemia; on the contrary, given intravenously, it could frequently induce ischaemia in the presence of coronary artery stenosis. This property was exploited for the diagnosis of coronary artery disease. The dipyridamole-induced ischaemia was detected by different techniques: ST-segment depression, thallium 201 scintigraphy and echocardiography. This review article describes the mechanisms underlying dipyridamole-induced ischaemia and discusses the value of this pharmacologic stress test for the detection of coronary artery disease.