The Thoratec HeartMate II heart pump has been linked to a 4-fold increase in blood clots in patients who were implanted after March 2011. Complications of a blood clot include heart attack and stroke, and patients may need emergency surgery to remove the HeartMate II and/or have a heart transplant. The sharp increase in HeartMate II blood clots has raised concern about a possible unannounced design change.
UPDATE: HeartMate II Linked to 4 Deaths, 5 Injuries
March 5, 2014 — Thoratec Corporation has issued a Safety Advisory after receiving reports of four deaths and five injuries associated with the HeartMate II LVAS Pocket System Controller. Patients are at risk of problems when exchanging an older controller for the Pocket Controller. Click here to read more.
What is the HeartMate II?
The Thoratec HeartMate II is a heart pump that continually pushes blood through the heart of people with end-stage heart failure. It belongs to a class of devices known as left ventricular assist device (LVAD) or system (LVAS). They are implanted in people who need a heart transplant or people who are too weak to undergo heart surgery. Approximately 4,000 LVADs are implanted every year, and the HeartMate II is used in 75% of people.
What is the problem with HeartMate II?
Like all cardiac implants, there is a risk that blood clots will form on the surface of the HeartMater II and cause a heart attack or stroke. Unfortunately, recent studies show that the risk of blood clots from HeartMate II has significantly increased since March 2011. Patients who develop this complication will need surgery to replace HeartMate II or a heart transplant. The sharp increase in HeartMate II blood clots after March 2011 has raised concern that Thoratec may have made unannounced design changes.
HeartMate II Blood Clots
November 2013 — The HeartMate II has been linked to an alarming, four-fold increase in blood clots in people who were implanted with the device after March 2011, according to a study published in the New England Journal of Medicine.
Researchers from the Cleveland Clinic and four other hospitals found that blood clots occurred within three months in 8.4% of patients who were implanted with the HeartMate II after March 2011, compared to just 2.2% of patients in earlier years.
Results were confirmed when researchers looked at data from INTERMACS, a federally-funded registry. However, that study showed a smaller increase in blood-clots — just 2% before March 2011, but 5% afterward.
The studies also showed that blood clots occurred more quickly in patients who were implanted with the HeartMate II. In patients who were implanted after March 2011, the median time until clot formation was just 2.7 months. In previous years, the median time was 18.6 months.
Side Effects & Complications of a HeartMate II Blood Clot
- Thrombosis (blood clots)
- Irregular heart rhythm
- Respiratory failure
- HeartMate II malfunction
- Heart attack
- Emergency heart transplant
- Surgery to remove and replace HeartMate II
HeartMate II Recalled
April 4, 2012 — Thoratec and the FDA have announced a HeartMate II recall. According to the Class 1 recall announcement, the problem was defective components that may inhibit blood-flow, erode into a patient’s body, or cut into the outflow graft. Complications may include severe injury or death.