Changing Heart Transplant Drugs Could Boost Kidney Function

THURSDAY, April 26 (HealthDay News) -- Changing a heart transplant patient's immunosuppression drug regimen may improve their kidney function and help prevent coronary artery disease, according to two Mayo Clinic studies.

Heart transplant patients must take immunosuppressive drugs to prevent their body from rejecting the new heart. Calcineurin inhibitors are the primary treatment, but they can cause kidney dysfunction and don't prevent transplant coronary artery disease, according to background information in a news release on the studies.

"Immunosuppression for heart transplant patients using calcineurin inhibitors has been essentially unchanged for 25 years, and the results have not been ideal," lead author and cardiologist Dr. Sudhir Kushwaha said in a prepared statement.

"Five to 10 years post-transplant, 10 percent of patients are on dialysis or need a kidney transplant. And 10 years post-transplant, 50 percent of patients are either waiting for another heart transplant because of coronary artery disease or have died as a result of it," Kushwaha noted.

In these studies, the Mayo team examined the use of the immunosuppressive drug sirolimus. Their research received funding from Wyeth Pharmaceuticals, which makes sirolimus (Rapamune).

One four-year study of 78 heart transplant patients found that gradually switching stable patients from calcineurin inhibitors to sirolimus resulted in improved kidney function. The study found no increase in heart rejection or difference in heart function.

The second study of 29 patients found that a gradual switch to sirolimus reduced development of changes related to transplant coronary artery disease.

"Based on our findings, patients should still receive calcineurin inhibitors as the primary immunosuppressant immediately after transplant, and the conversion to sirolimus must be gradual in order to prevent rejection," Kushwaha said.

The studies were expected to be presented April 26 at The International Society for Heart & Lung Transplantation's annual meeting, in San Francisco.

More information

The MedlinePlus Medical Encyclopedia has more about heart transplantation.

SOURCE: Mayo Clinic, news release, April 26, 2007