NEJM study ties Thoratec's HeartMate pump to blood clots

Thoratec's ($THOR) robust HeartMate pump-sales face a new challenge: research that ties the device to life-threatening blood clots.

Bloomberg reported on a study published recently in the New England Journal of Medicine that concluded the rate of blood clots relating to HeartMate II at three major hospitals involved in the study has "been increasing ... and is associated with substantial morbidity and mortality."

Researchers pooled data from 895 HeartMate II procedures at Ohio's Cleveland Clinic, Duke University Medical Center and Missouri-based Washington University Barnes-Jewish Hospital from 2004 through 2013. Out of that patient pool, they found reports of 72 blood clots in 66 patients, Bloomberg noted. HeartMate II is a left ventricular assist device designed to aid an ailing heart as a bridge to transplant.

The researchers aren't recommending that surgeons stop using the devices. It's also important to note that their research simply notes the increased blood clots, acknowledging that the precise cause isn't yet known. Instead, the study authors have said that HeartMate's risk profile needs a new update with the blood clot issue factored in. Lead author and Cleveland Clinic cardiologist Randall Star also told Bloomberg that the data shows researchers need to better understand HeartMate's limitations and how to manage them.

FierceMedicalDevices could not reach Thoratec for comment before deadline.

HeartMate faced an FDA Class I recall in 2012 in the wake of a faulty component, and the company issued new instructions to prevent improper implants around the same time. Otherwise, HeartMate has generally soared without problems in the U.S., and the company has made headway expanding overseas, notably gaining Japanese approval for HeartMate II as a bridge-to-transplant therapy for patients with advanced heart failure.

But negative research news could still have a sobering impact on HeartMate pump sales down the line. California-based Thoratec booked $126.4 million in revenue during its 2013 third quarter, 7% higher than the same period in 2012. HeartMate generated nearly $113 million of the total. So bad news for HeartMate could mean a hit to Thoratec's bottom line.

- read the Bloomberg story
- here's the NEJM study