Ischemic cascade – sequence of changes in myocardial ischemia

Ischemic cascade – sequence of changes in myocardial ischemia

Ischemic cascade is the temporal sequence of changes due to myocardial ischemia. Ischemic episodes are initiated by a supply – demand mismatch in myocardial oxygen delivery. There is a sequential decrease in left ventricular compliance, decreased myocardial contractility, increased left ventricular end diastolic pressure, ST segment changes on the electrocardiogram and finally angina pectoris, if the ischemia reaches a clinical threshold.

Sometimes angina may be absent as in silent ischemic episodes. The electrocardiographic changes in repolarization are noted twenty to thirty seconds after a coronary occlusion. It is noteworthy that clinical anginal symptoms are the last in the temporal sequence of the ischemic cascade.