U.S. medical device reviewers said HeartWare International Inc’s blood pump seemed to help people with severe heart failure but raised concerns about device-associated clotting rates and stroke. However, analysts said the review by Food and Drug Administration staff raised few new issues and bet the device would be approved, sending HeartWare shares up 4.3 percent to $70.01 in morning trading on Nasdaq. FDA staff also said clinical trial results for the mechanical heart-assist device, or the HeartWare ventricular assist device (HVAD), may have missing data and are difficult to compare with a registry of patients.
