Design Flaws in Heart Device Cause Air Leaks and Patient Deaths

The devices are often a last resort for very ill patients, but that the risks may outweigh the benefits. 

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A medical device meant to save lives is now under scrutiny for potentially deadly design flaws.

The HeartMate 3— billed as a last resort for end-stage heart failure patients ineligible for transplants—has been linked to at least two deaths involving fatal air embolisms.

The mechanically assisted pumps catastrophically malfunctioned in both cases, sending bubbles into the bloodstream, triggering strokes, and eventually causing irreparable organ damage.

The Only Heart Pump of Its Kind

Air embolisms are rare but almost always life-threatening events. They occur when air bubbles enter the arteries and veins, interrupting blood flow. This causes an inadequate blood supply to reach vital organs, including the brain, spinal cord, kidneys, spleen, gastrointestinal tract, and heart.

The HeartMate 3 is a left ventricular assist device—a type of mechanical heart pump first introduced over 60 years ago. However, the specific HeartMate 3 model was approved in 2017 for patients awaiting a heart transplant, and it remains the only device of its kind approved by the U.S. Food and Drug Administration.

In 2018, the HeartMate 3 received expanded approval for long-term therapy.

A Fatal Case From 2019

One of the two cases involved 67-year-old Arvid Hermann, diagnosed with systolic heart failure which occurs when the left ventricle is too weak to pump properly. Deemed too ill for a transplant, Hermann opted for a HeartMate 3 implant, as reported by CBS News.

Surgeons noticed air filling Hermann’s aorta after inserting the device, according to the Journal of Heart and Lung Transplantation.  They tried unsuccessfully four times to halt air flow before removing and replacing the pump. Though the second HeartMate 3 initially seemed effective, Hermann later suffered seizures and symptoms of a fatal air embolism, including multiple organ failure, after being moved to the critical care unit.

Per the journal researchers, the embolism resulted from an internal loose connection allowing air to flow along the left ventricle. If implanted loosely, poor pump fixation can occur “This case serves as a reminder of the importance at the time of implant to add two checks on the list before implantation of the pump,” the authors wrote.

Another Fatal Case, From 2021

Another patient experienced a similar complication—air entering the bloodstream after the HeartMate 3 pump failed to lock properly into place. Per the FDA report, the initial device placed was likely damaged, enabling a large amount of air into the left ventricle.

“A decision was made while in the operating room and not able to get off by-pass to exchange the pump,” the FDA report reads.

The report also states the second pump was attached without further air entry. However, the right ventricle began failing soon thereafter. Though taken back to the ICU, the patient ultimately did not survive, suffering intractable seizures leading up to their death.

An analysis by device maker Thoratec, a subsidiary of Abbott Laboratories, found bent locking arms in pumps from both fatalities. Still, the company deflected responsibility, noting that heart failure and stroke are known implantation risks, as is mortality.

“Right ventricular dysfunction, especially when combined with elevated pulmonary resistance may limit the effectiveness of the left ventricular assist system due to reduce filling of the pump,” the company wrote.

HeartMate Line Plagued by Safety Issues

This is not the first controversy linked to Thoratec’s HeartMate pumps. Per an FDA database analysis, over 4,500 death reports have been associated specifically with the HeartMate 3. Moreover, in 2017, nearly 29,000 HeartMate II devices were recalled after 26 patients died attempting home controller changes without supervision.

Prior to that, in 2014, Thoratec issued a recall of the HeartMate II due to four deaths and five injuries related to patients switching controllers.

Federal law requires device makers to submit adverse event reports within 30 days. The data helps regulators and policymakers identify issues meriting further investigation. Reports may be filed voluntarily by medical personnel or other involved parties.