Echocardiographic Signs of Ischemia

The response of left ventricular function to ischemia is monotonous and independent of the stress employed. The same echocardiographic signs can be found in transient ischemia and acute infarction. The difference is in the time sequence, and from an echocardiographic viewpoint myocardial ischemia is a “reversible” myocardial infarction. The cardinal sign of ischemia is the transient, regional wall motion abnormality – the cornerstone of diagnosis. There are other ancillary signs of severity which may occasionally help in disease severity stratification, such as left ventricular cavity dilation, acute severe mitral insufficiency, fall of stroke volume, or appearance of ultrasound lung comets on the chest. In leading-edge stress echo environments today, wall motion analysis can be coupled during vasodilator stress with assessment of coronary flow reserve, which further expands the diagnostic and prognostic information during stress echocardiography. A regional wall motion abnormality is associated with underlying significant epicardial coronary artery stenosis. Normal function with normal coronary flow reserve expresses an absence of anatomic and functionally significant stenosis of the epicardial artery as well as microcirculatory integrity. On the contrary, a normal wall motion with abnormal coronary flow reserve is associated with either a mild-to-moderate hemodynamically significant epicardial stenosis or significant microcirculatory disease. The two markers are also prognostically complementary, since wall motion abnormalities identify troublemakers in the short run (months), and coronary flow reserve reduction – in the absence of wall motion disturbances – troublemakers in the long run (years).