Are familial Mediterranean fever (FMF) patients at increased risk for atherosclerosis? Impaired endothelial function and increased intima media thickness are found in FMF.

control (10%) arms. In the control group, 2 patients died. There was no significant change in functional class or left ventricular function in this group. In summary, 24 patients underwent intracoronary stem cell injection with coronary sinus blockage. Four patients died during the 6-month follow-up. Overall EF showed a small but significant improvement of 5.4%. There was a decrease in end-systolic volumes, but no change in end-diastolic volumes. Endomyocardial biopsy done at 3 months showed no significant change in the number of myocytes or capillaries, but the ratio of capillaries to myocytes showed an insignificant increase. There were soft data to suggest cell proliferation (binucleate cells and Ki 67 positivity). This is the first study of stem cell therapy in dilated nonischemic cardiomyopathy. Over a 6-month period, there was a small albeit significant improvement in ventricular function. Previous clinical studies have also shown a small degree of change in ventricular function of a similar magnitude (1,2). Laboratory experiments in nonischemic dilated cardiomyopathy (3) have previously suggested that benefit from stem cell therapy in this group comes mainly from a decrease in fibrosis and an increase in vascularity, but no evidence has been found supporting transdifferentiation of stem cells to myocytes. Our data also suggest that the benefit of stem cell therapy could be a paracrine effect with changes in vascularity, perhaps stimulation of cell proliferation, or by some still-unexplored mechanism. We did not find any evidence of transdifferentiation. In this study we wish to highlight a number of issues. It is the first study to show the benefit of stem cells in nonischemic dilated cardiomyopathy, and the first study that uses coronary sinus occlusion to increase cell contact time. It is also the first study in which we have endomyocardial biopsies performed after stem cell therapy. It provides a stimulus for exploring the benefits of stem cell therapy in nonischemic dilated cardiomyopathy. A double-blind study is being planned to further explore the benefit seen in this preliminary study. The small magnitude of benefit could perhaps be because all patients in this study were in very late stages of their cardiomyopathy, and we probably need to consider stem cell therapy at a much earlier stage. Endomyocardial biopsy, performed for the first time in stem cell therapy, shows no evidence of transdifferentiation of stem cells to myocytes but provides soft data pointing to a possible paracrine effect.