Seventy two clots occurred in 66 patients at three institutions where 895 devices were inserted from 2004-2013.
However, doctors aren't necessarily going to stop using HeartMate II. "I don't think anybody that's in this field is ready to say 'Gee, we have to stop using these,'" says cardiologist Randall Starling. "The alternative isn't good. But we have to better understand their limitations and how to manage them."