Left Ventricular Assist Devices (LVADs) Linked to Risk of Cognitive Problems: Study

New research suggests that Left Ventricular Assist Devices (LVADs), such as the popular Thoratec HeartMate II and other similar implants, may keep the heart functioning properly at the cost of some impact on the patients ability to think clearly and remember certain things. 

In the latest issue of the medical journal Circulation: Cardiovascular Quality and Outcomes, researchers from Saint Luke’s Mid-America Heart Institute looked at the potential cognitive side effects of LVADs. Elderly patients were found to be at a particularly increased risk of memory loss and decline in cognitive function after receiving a HeartMate II or similar devices.

LVADs are implanted in patients who have suffered advanced heart failure (HF). Recipients’ hearts are often considered too weak to efficiently pump blood. They have been widely used in individuals who are waiting for a heart transplant or who are too weak to undergo such a procedure.

Researchers in the latest study said found while those implanted with the devices generally see a marked improvement in both quality of life and odds of survival, the devices have also been associated with an increased risk of stroke and a loss of cognitive functioning.

The study was presented by lead researcher Dr. Timothy J. Fendler at the Quality of Care and Outcomes Research 2015 Scientific Sessions in Baltimore, Maryland. He and his fellow researchers looked at data on more than 4,400 patients who underwent LVAD implantation between May 2012 and December 2013. They assessed cognitive function on 1,173 of those patients, looking for signs of cognitive impairment as well as signs they may have suffered subclinical strokes.

According to their findings, patients had nearly a 30% chance of suffering cognitive decline in the year after implantation. Patients 70 and older were at more risk than younger patients, the researchers determined. They also found an increased risk among patients undergoing destination therapy, meaning the implant was permanent and they were not candidates for a heart transplant.

However, researchers note that more patients saw an increase in cognitive function than who lost functioning.

“Patients with advanced HF who receive LVADs are likely to experience improved survival. However, this device also exposes patients to new risks, such as cognitive decline,” Fendler concludes. “We think that the high incidence of cognitive decline reported herein is a particularly important finding given the assumption that long-term neuro-cognitive function should improve when cerebral perfusion is restored because of LVAD therapy, just as function of other end organs has been shown to do.”

Thoratec HeartMate II Health Concerns

The study’s findings come about a year after concerns over the Thoratec HeartMate II LVAD, also known as a left ventricular assist system (LVAS), led to a recall due to problems with certain pocket controllers. Patients with older versions of the controller had a hard time understanding how to program new ones, resulting in at least four deaths and five serious injuries.

The FDA ultimately determined that an Urgent Medical Device Correction Letter the company sent out constituted a Class I Thoratec HeartMate II recall.

The recall came among increasing concerns over the potential risk of blood clots linked to the device.

A study published in November 2013 highlighted recent increases in the number of blood clot-related problems with the Thoratec HeartMate II that have been seen since March 2011. After examining data from three different hospitals, researchers from Cleveland Clinic were able to identify that over the past few years there has been an increase in the rate of clot formation during the months after the HeartMate II was implanted, confirming what doctors at the hospital suspected based on their own experiences.

The manufacturer has denied that any changes were made to the device and indicate that the small study does not accurately portray the device’s performance. In January 2014, a Thoratec HeartMate II class action lawsuit was filed by investors who say the company withheld important information about the safety and efficacy of the device, which has caused the stock price to decline.