External counterpulsation


External counterpulsation therapy is a procedure that may be performed on individuals with angina, heart failure, or cardiomyopathy.

Medical uses

The FDA approved the CardiAssistTM ECP system for the treatment of angina, acute myocardial infarction and cardiogenic shock under a 510 submission in 1980 . Since then, additional ECP devices have been cleared by the FDA for use in treating stable or unstable angina pectoris, acute myocardial infarction, cardiogenic shock, and congestive heart failure.
Some reviews did not find sufficient evidence that it was useful for either angina or heart failure. Other reviews found tentative benefit in those with angina that does not improve with medications.
For stroke due to lack of blood flow a 2012 Cochrane review found insufficient evidence to make conclusions.

Method

While an individual is undergoing ECP, he/she has pneumatic cuffs on his or her legs and is connected to telemetry monitors that monitor heart rate and rhythm. The most common type in use involves three cuffs placed on each leg. The cuffs are timed to inflate and deflate based on the individual's electrocardiogram. The cuffs should ideally inflate at the beginning of diastole and deflate at the beginning of systole. During the inflation portion of the cycle, the calf cuffs inflate first, then the lower thigh cuffs and finally the upper thigh cuffs. Inflation is controlled by a pressure monitor, and the cuffs are inflated to about 200 mmHg.

Physiological considerations

One theory is that ECP exposes the coronary circulation to increased shear stress, and that this results in the production of a cascade of growth factors that result in new blood vessel formation in the heart..