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Patient's Ventricles Removed as Bridge to Heart Transplant

— Rare therapy a variation of BIVAD support

MedpageToday
A computer rendering of the human heart cut in half with a scalpel between the two halves

Brian Pedigo was originally referred to Baptist Memorial Hospital in Memphis, Tennessee, for a left ventricular assist device (LVAD), but the 41-year-old's condition deteriorated rapidly.

He was experiencing intractable ventricular tachycardia and ventricular fibrillation and going into cardiogenic shock. With both ventricles in bad shape, his team of cardiologists couldn't just put in an LVAD. On top of that, Pedigo's thin frame and the use of extracorporeal membrane oxygenation (ECMO) to support him in the ICU meant he likely wasn't a candidate for an .

The heart team was concerned the arrhythmias would not resolve even with both ventricles supported, leaving Pedigo at greater risk for blood clots, among other complications.

So they decided to remove both ventricles, leaving the atria in place. Two ventricular assist devices were configured to serve as a total artificial heart, and a silicone breast implant was used to maintain the space in the chest cavity so that a heart transplant remains an option in the future.

"It's not really a ventricular assist device; he doesn't have a ventricle to assist. It's more of a total artificial heart," said Rachel Harrison, MD, the thoracic surgeon at Baptist who performed Pedigo's surgery. "The goal is for the pumps to improve his blood flow, so he can recover, get stronger, and qualify for heart transplant."

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Pedigo with grandchildren Dallas and newborn Penelope who came into the world as Pedigo was going into surgery. Photo by Michaela Morris

LVADs were initially used exclusively as bridge to heart transplant, but have become increasingly common as destination therapy, supporting patients for years, according to Martin Strueber, MD, chief of cardiac surgery and thoracic transplantation at Baptist Memorial, who worked on Pedigo's case.

If the right ventricle is also failing, heart teams have a range of options to create a bridge to heart transplant, including using two VADs without removing the ventricles, or implanting a total artificial heart. In some cases, a temporary pump is placed on the right side, said Mary Walsh, MD, of St. Vincent Heart Center of Indiana and immediate past president of the American College of Cardiology, who wasn't involved in Pedigo's case.

Removing both ventricles and replacing them with VADs, as was done for Pedigo, is not a frequently used technique, but "other large VAD centers have used this strategy," Walsh said. St. Vincent has used it twice in the past year.

To be a candidate for such a procedure, patients must be very sick, but they also have to have the potential to be strong enough for heart transplant surgery, said Jason Katz, MD, director of cardiovascular clinical care at Duke University, which is one of the U.S. centers that pioneered the dual-VAD technique.

"These are all outside-the-box decisions," said Katz, who also wasn't involved in Pedigo's care. "It's a niche salvage therapy."

The perioperative period is considerably more challenging and complex with dual-VAD therapy, Katz said. Patients must manage two sets of controllers and batteries, and robust coordination of outpatient care is required.

The risk of stroke, bleeding, infection, device failure, and damaged blood cells seen with LVADs remains with dual VADs, though it is difficult to compare risks as the patient population for dual VAD is generally sicker with more profound organ dysfunction, researchers said.

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Two battery packs keep Pedigo's blood circulating. Because the pumps move his blood continuously, he has no pulse. Photo by Michaela Morris

Strueber expects to see the use of dual pumps continue to expand as the technology improves, particularly with modifications to the batteries that allow more freedom of movement. He said he sees Pedigo's procedure as bringing surgeons one step closer to an artificial heart that would offer a long-term alternative to transplants.

"It's not at that point yet," Strueber said. "But I think we're getting very close."

Harrison declined to provide a prognosis for Pedigo, but said the team is pleased with his progress toward regaining his strength and ultimately qualifying for heart transplant.

Pedigo has struggled with coronary artery disease for nearly a decade. Once much heavier and a tobacco user, he had his first heart attack at 32 and a massive heart attack in 2017. He had open heart surgery in the spring, but his condition worsened through the summer.

"I couldn't eat, I couldn't sleep," said Pedigo, who lost 60 pounds. "I was dying."

He had his ventricles removed and the VADs placed in early September and was released from the hospital about a month later. Pedigo said his strength is steadily improving and he recently felt well enough to work on his 1989 Ford Mustang, a project he hasn't been able to touch in months. Most importantly, he has been able to to spend time with most of his family, including his sixth grandchild, Penelope, who arrived as he was going into surgery.

"The [pumps] are keeping me alive," he said, "but they're not going to last forever."

Editor's note: Strueber previously worked at Newark Beth Israel Medical Center in New Jersey, where the heart transplant program following reports that it kept vegetative patients on life support in order to meet federal benchmarks.