Unlike CCU and OR, IABC is not a household acronym. But its increasing uses in the coronary care unit and in the operating room suggest that it is well on the way to attaining this distinction. Replacing the electrocardiogramtriggered electrical pump, the currently used intra-aortic balloon counterpulsation provides a simple method for withdrawing blood from the aorta during systole and returning it during diastole. A balloon, which is attached to a catheter introduced through the femoral artery into the descending thoracic aorta, is rapidly inflated with helium in early diastole and then deflated in early systole.
The principle of counterpulsation as a circulatory "assist" in cardiogenic shock was proposed by Kantrowitz and Kantrowitz1 in 1963. Its rationale is eminently logical. Reduction of blood volume in the ascending aorta during systole decreases impedance to the emptying of the left ventricle, thereby reducing its afterload. As a result, one can expect