Mechanische Herz-Kreislauf-Unterstützung in der Kardiologie

Abstract

One out of 13 patients with an acute myocardial infarction is endangered of cardiogenic shock. In addition, acute valvular leakage, shunt vitiae, and acute myocarditis can lead to acute myocardial failure. As a therapeutic option, mechanical assist devices offer cardiac support and hemodynamic stabilization under these circumstances. The following minimal-invasive devices are used in cardiology and intensive care medicine: intra-aortic balloon pulsation (IABP), intra-vascular axial screw pumps, extra-corporal centrifugal pumps with and without additional membrane oxygenator. The IABP improves left ventricular function by a systolic reduction of the after-load, and an increase of diastolic blood pressure dependent on myocardial function. In contrast, axial screw pumps and centrifugal pumps can provide circulatory support independently of myocardial function. Mechanical assist devices can prevent irreversible damage not only by offering a reduction of myocardial work load, but also by improving organ perfusion in cardiogenic shock situations. Another indication for mechanical circulatory support depicts high-risk coronary angioplasty if the left ventricular ejection fraction is severely reduced or the target vessel supplies more than 50 % of vital myocardium. In case of irreversible heart failure, turbine pumps or centrifugal pumps offer a stabilization for the patient's transfer to a cardiac surgery center. They can also be used for bridging to heart transplantation in acute situations. Technical improvements will enhance the use of mechanical assist devices in the near future. Especially the development of portable emergency devices will enrich therapeutic possibilities in cardiology and intensive care medicine.