Changing patterns of intra-aortic balloon pump assistance.

Intra-aortic balloon pump assistance (IABPA) for cardiogenic shock is well established. The response to balloon pumping and patient survival are better after low output from cardiotomy than after myocardial infarction. Elective use of IABPA preoperatively allows an extra margin of safety for patients with acute coronary insufficiency, significant left main coronary artery stenosis, or depressed left ventricular function. However, advances in monitoring techniques during the induction of anesthesia and weaning from cardiopulmonary bypass support, as well as improved methods for myocardial preservation, have reduced the requirements for elective IABPA. Current indications for preoperative IABPA include: patients with acute coronary insufficiency who are totally unresponsive to full medical management and who continue to have pain and electrocardiographic changes at rest, and patients with serious left main coronary artery stenosis who also have acute coronary insufficiency or depressed left ventricular function. The survival of patients with valvular heart disease and left ventricular dysfunction is not improved with preoperative IABPA, while most patients with depressed left ventricular function from coronary artery disease may now undergo revascularization uneventfully, although inevitably some will still require postoperative IABPA.