Left ventricular assist devices are implanted only in patients who are eligible for cardiac transplantation. These devices are used as bridges to transplantation. There are three left ventricular assist devices presently available:
Thoratec, the HeartMate, and Novacor.
The Thoratec system is paracorporeal: the pneumatic pump resides externally on the surface of the abdomen and is connected by cannulas to the heart and the ascending aorta. Figure 2 is taken from the Rose et al. study which reviewed long-term use of left ventricular assist devices. In the second and third systems the device is placed entirely within the chest cavity and abdomen. The energy conduit and vent, a drive line, is brought through the skin to the external energy source. Major problems with these systems include: a high incidence of infection of the device that usually occurs between 3 and 6 months, a high rate of bleeding by 6 months, and a probability of device failure greater than 33% at 2 years.
B. Clinical Study: Rose et al.
Study question: Does long-term use of left ventricular assist devices enhance survival and the quality of life?
Methods: Patients (129) with end-stage heart failure and eligible for cardiac transplantation were randomized to receive a left ventricular assist device (68 patients) or optimal medical management (61). All patients had symptoms classified as of New York Heart Association class IV heart failure. Results: The device caused a significant reduction in risk of death as compared with the medical therapy group p ¼ 0.001). Figure 3 shows the rates of survival at one year: 52% for the device group and 25% in the medical group ( p ¼ 0.002). The primary end point was 48% lower in the device group. Importantly, at 2 years survival was not significantly different: 23 and 8%, respectively ( p ¼ 0.09).

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