The intra-aortic balloon pump and other methods of mechanical circulatory support

Mechanical circulatory support plays an increasing role in the management of patients with cardiac failure. Of the several forms to be discussed, intra-aortic balloon pump (IABP) counterpulsation is the most widely utilized. This involves percutaneous insertion of a balloon catheter through the femoral artery that inflates during diastole and deflates prior to systole, improving ventricular performance by simultaneously increasing myocardial oxygen supply during diastole and reducing myocardial oxygen demand by reducing afterload. Other forms of more advanced mechanical circulatory support that will be discussed include extracorporeal membrane oxygenation, ventricular assist devices and the total artificial heart. These technologies can replace rather than simply support cardiac function, as in the case of the IABP, and as such patient selection is critical. The use of these technologies must be balanced against potential complications which can be significant.