Forum ekspertów
Use of left-ventricular assist devices in treatment of advanced heart failure

Left-ventricular assist devices (LVAD) are totally implantable pumps able to support circulation in patients with advanced heart failure by draining blood from the ventricular chamber into the aorta, thereby replacing function of the left-ventricle. Due to the totally implantable and compact LVAD design, device ability to sustain normal cardiac output for few years and patients’ ability to exercise, rehabilitate and be discharged home soon after surgery, LVAD therapy has become increasingly popular in 1990s, primarily used as a ”bridge” to heart transplantation in patients with profound circulatory failure. Currently, nearly two hundred centers worldwide perform routine LVAD implantations in the sickest heart failure patients, and in large volume centers 20 to 30% of all heart transplant candidates are supported with LVADs [1, 2]. Over the last three decades, the field of mechanical circulatory support has made a tremendous progress. The design and safety profile of various new LVADs evolved a great deal. There are currently several types of circulatory assist devices, including those which support one- and/or both ventricles [3, 4]. This article will focus on the experiences with the most widely used LVAD system in the United States, HeartMate Left-Ventricular Assist Systems, produced by the market leader Thoratec Incorporation, Pleasanton, California, which has accounted for more than 4,500 of the LVAD implantations worldwide.
Long-Term Implantable Left-Ventricular Assist Devices
The two most popular long-term left-ventricular assist devices are HeartMate XVE pump (Thoratec Laboratories Corp., Pleasanton, CA) and Novacor (WorldHeart, Ottawa, Canada). In the United States HeartMate XVE is the only approved device to be used as ”bridge” to transplant or ”destination therapy”. In Europe, the Novacor LVAD has unrestricted approval for use as an alternative to transplantation. Both LVAD models are a totally implantable pusher plate pumps that can fully sustain systemic circulation and adapt to increased cardiac output needs with exercise. They can generate stroke volume up to 80 mL, pulsatile flow up to 10L/min and pulse rate up to 120 beats per minute, Figure 1. One of the major advantages of the HeartMate pump over Novacor is its textured internal reservoir surface which encourages adherence of circulating endothelial cells and formation of a pseudointima, thus obviating the need for...


View full text...