In a national first, a donor heart held its beat for nearly three hours in its transport carrier before it was transplanted into a patient.
The organ was stored in an experimental device built to keep it pristine and functioning, a state that could reduce the risk of rejection and increase the chances for successful transplantation, said Dr. Kenneth McCurry, director of cardiopulmonary transplantation at the University of Pittsburgh Medical Center's Heart, Lung and Esophageal Surgery Institute.
Unlike the conventional storage method, in which the organ is kept on ice, the device allows blood and oxygen to perfuse the heart.
"The heart suffers less injury from being [without oxygen] and therefore hopefully will work better," Dr. McCurry explained. "Patients could do better, get out of the hospital quicker and, because of less injury around the time of the transplant, hopefully could have better intermediate and long-term outcomes, as well."
On April 8, the surgeon transplanted a heart donated by a 46-year-old male into Richard Jackson, 47, of Portage, Cambria County, whose own organ was damaged by congestive heart failure and pulmonary hypertension. Mr. Jackson was discharged from the hospital on April 30 and is well.
Since then, two more people have received hearts that were kept beating for around six hours in the device, called the Organ Care System. The second has been discharged home, and the third is still in the hospital.
"All patients are doing well with no device-related complications," Dr. McCurry said.
In a 20-patient trial sponsored by Andover, Mass.-based manufacturer TransMedics Inc., the system is being evaluated at UPMC, the Cleveland Clinic, UCLA, the University of Chicago and Brigham and Women's Hospital.
Results from a European study of the device look promising, Dr. McCurry said. If all goes well, a larger randomized study will be conducted to determine whether the device is better than conventional organ preservation techniques.
Transplant surgeons stop the heart for removal from the donor. Instead of putting the organ on ice, it is placed in the device along with about 1.5 quarts of the donor's blood and nutrient solutions. The blood circulates through the donor heart and the device, which contains an oxygenator and a heater.
For about five to seven minutes, the heart is still. Then, as the blood warms the tissue, it spontaneously resumes beating, which oxygenates the tissue, Dr. McCurry said.
"In all cases thus far, that's what's happened," he said. But, "if we needed to, we could pace the heart."
The organ is stopped again for about 40 minutes as it is readied to be transplanted into a recipient. So the ischemia time, meaning the time the tissue is deprived of oxygen, is usually about 45 minutes in total.
Surgeons try to transplant hearts that have been stored on ice within four hours to limit tissue damage from prolonged ischemia, Dr. McCurry said. The device could extend the amount of time the organ can be safely stored.
If that is possible, current practices that favor local distribution of donor hearts might change. And, he added, if transplanting healthier, better functioning hearts mean patients get out of the hospital sooner after transplant, need less time in intensive care and don't have to be readmitted as often for rejection or other complications, health care costs would be reduced as well.
Dr. McCurry said the storage device could also give doctors the opportunity to assess whether organs that might otherwise be deemed unsuitable do, in fact, function well enough for transplantation.
The manufacturer is planning to develop systems to extend preservation of other donor organs.
[18May07, http://www.post-gazette.com/pg/07138/787080-32.stm, Anita Srikameswaran, Pittsburgh Post-Gazette, can be reached at [email protected] or 412-263-3858. Organ Care System, see www.transmedics.com/wt/page/how_works; N Valko RN, 20May07]