 Despite favorable survival and quality of life outcomes, MCSDs do have severe and sometimes life-threatening complications, including infection, thrombosis, and device failure. The development of new procedures and devices to reduce these complications will be expedited by the work of the registry involving the systematic, independent analysis of MCSD implantation procedures and outcomes. The National Heart, Lung, and Blood Institute NHLBI will collaborate with the Centers for Medicare and Medicaid Services CMS and the Food and Drug Administration FDA in monitoring the work of the registry to permit the development of standard reporting of patient characteristics, indications, implantation procedures, and adverse events. 