PHILADELPHIA — The bridge-to-transplant approach for stabilizing patients prior to heart transplantation is working.
Of patients who received a mechanical circulatory support device as a bridge to heart transplant in 2002–2004, half (50%) of those over age 50 and three-quarters (74%) of those under 30 survived to receive a heart transplant during the first year after receiving the device, Marshall I. Hertz, M.D., said at the annual meeting of the International Society for Heart and Lung Transplantation.
“The findings show, in a nonanecdotal way, that you can get a lot of patients to [heart] transplant who otherwise wouldn't get transplanted, said Dr. Hertz, professor of medicine at the University of Minnesota in Minneapolis, and medical director of the International Heart and Lung Transplant Registry.
“The results of several studies have shown that patients who have a heart transplant after receiving a ventricular assist device can do better than patients who are transplanted with no device. It's paradoxical, because the sickest patients get devices, but then they are stabilized and they can get physical rehabilitation and improved nutrition, and they become better candidates for heart transplantation a few months later. The bridging idea started as a last ditch effort for patients, but now it's viewed as interim therapy,” Dr. Hertz said in an interview.
Starting in January 2002, the registry began a voluntary program for submitting case reports for patients who received a mechanical circulatory support device, and as of Dec. 31, 2004, 699 patients were registered. They had received a total of 831 devices at 60 centers worldwide. Follow-up data were available for 655 patients, including 513 who had received a device as a bridge to transplant and 78 patients who received a device as destination therapy. Also, 35 patients received a device as a bridge to recovery, and 29 patients had received a device with an unspecified purpose.
Among all patients who received a device, the actuarial survival rate was 83% after 1 month, 74% after 3 months, 67% after 6 months, and 50% after 1 year.
Survival was linked with age in patients who received a device as a bridge to transplant. Among 292 patients who were aged older than 50 years, mortality was 37% during the first year after they received the device. In contrast, among 52 patients aged younger than 30 years, first-year mortality was 13%, reported Dr. Hertz. A similar analysis was not reported for the remaining 169 patients who were aged 30–50 years.
“The survival to 12 months is not as good as we'd want; additional technical improvements are needed,” said Dr. Hertz.
During 12 months of follow-up of the entire group of 513 patients who received bridge-to-transplant devices, 501 patients had infection episodes, 302 had bleeding episodes, and 75 has thrombotic episodes. The high rate of infection was not surprising, said Dr. Hertz. Infections occur primarily as a consequence of the transcutaneous catheters that devices currently require.
Most of the 78 patients in the registry who received devices as destination therapy were ineligible for heart transplants either because of advanced age (49%) or comorbidity (36%). An additional 10% received a device without listing for a transplant because of fixed pulmonary hypertension.
The long-term prognosis for these patients was not good, especially among older patients. Of the 41 patients in the registry who received destination therapy and were at least 65 years old, 52% died within 6 months of receiving the device, and 74% died within 1 year. Among the 37 patients aged younger than 65 years, 13% died within 6 months and 39% were dead after 1 year.