TUESDAY, Nov. 17 (HealthCare News) -- Patients who received bone marrow stem cell transplants during coronary bypass surgery (CABG) experienced "excellent long-term safety and survival," say German researchers, who also noted the first promising results for stem cell transplantation during mitral valve repair.

The study included 35 patients who received CD 133+ bone marrow stem cell transplantation during CABG, 20 patients who received only CABG surgery and 10 patients who received stem cell transplantation after mitral valve repair.

Long-term survival among patients in the stem cell transplant/CAGB group was up to five years. Three patients in the stem cell/mitral valve repair group died six months to a year after surgery, including two who developed progressive heart failure, the researchers noted.

The University of Rostock researchers found no sustained or adverse tissue changes in the patients who received stem cell transplants. The stem cell/CABG patients scored better on assessments of clinical effects than those who had only CABG surgery. Both CABG groups had preserved ventricular function, but left ventricular end diastolic volume decreased in the stem cell/CABG patients.

Decreased left ventricular end diastolic volume was also noted in the stem cell/mitral valve repair patients. Two years after the procedure, improved heart function was seen in these patients.

Blood flow scores increased significantly for CABG and mitral valve repair patients who received stem cell transplants, the study authors noted.

The study was to be presented Tuesday at the American Heart Association's annual meeting in Orlando, Fla.