Stanford Brings Total Artificial Heart to Transplant Program

Stanford Hospital & Clinics will become the first hospital in northern California to offer patients with right or bi-ventricular heart failure a new option – the Syncardia Total Artificial Heart (TAH) – as a bridge to heart transplant. Currently there's a very strong option for patients with left ventricular failure, the Left Ventricular Assist Device or LVAD. Stanford's Mechanical Circulatory Support (MCS) team, led by surgical director Richard Ha, MD, and medical director Dipanjan Banerjee, MD, has been using LVADs successfully for years as both a bridge to transplant and as a destination therapy for patients who are unable to have a heart transplant.

But when the heart's right ventricle fails as well, there aren’t as many good treatment options, says Ha, clinical instructor of cardiovascular surgery. "We have a certain number of patients who come to us with right ventricular failure," he says, "and we have had to send them to other centers in Washington or Los Angeles to receive this device."

But with the addition of the total artificial heart, Stanford can address every type of end stage heart failure, says Banerjee. "As a tertiary care center at the forefront of mechanical circulatory support, we needed a device that would address both ventricles for that subset of patients whose problems were not being adequately addressed by LVAD."

But Stanford was not willing to use previous models of artificial hearts, which had poor outcomes and were not durable for long periods of time. "Stanford is at the forefront of using emerging technologies that are safe for their patients," says Ha. "We wanted to make sure that what we are doing is established and offers good outcomes for our patients."

The Syncardia heart has been used successfully in patients for more than one year. Plus it comes with a portable battery, the Freedom Driver, which allows patients to be out of the hospital while awaiting transplant. In the past, patients with artificial hearts had to remain hospitalized because the pumps needed to operate them required so much power.

"The Freedom Driver made us strongly consider this therapy because we are very interested in quality of life for our patients, not just getting them to transplant," says Banerjee, clinical assistant professor of cardiovascular medicine. "We want our patients walking into transplant, not crawling in.”

Early intervention aids success

"Implanting the total artificial heart is a very different procedure from implanting an LVAD," says Ha. With an LVAD implant, the patient's heart remains nearly intact, and the surgeon attaches the LVAD to act as a pump in conjunction with the heart. But with the Syncardia device, surgeons remove almost the entire heart and replace it with the bio-prosthetic heart.

The patients who will get these devices tend to be sicker than your average assist device patients, he adds. Thus, the operative time and recovery time are longer. But for all patients who require an assist device as a bridge to transplant, both physicians say it is best to place the device in patients before they become too ill to recover well from surgery. "The longer we wait on these patients," says Banerjee, "the longer their recovery period and the worse candidate they are when they get to transplant."

The Stanford mechanical support team has begun educating referring providers about referring patients to the program earlier. Patients who are on an optimal medical regimen, but continue to fail despite these best efforts, should be referred to the MCS team for evaluation. Worsening kidney function, more than one hospitalization for heart failure and intolerance to medications are all red flags, signs that a patient may need additional support for their heart, says Banerjee.

"I see heart failure as cancer of the heart," says Ha. "Once you have that diagnosis, you really need to move on it and treat it aggressively."

Beyond the bridge

With the advent of medical therapies for heart disease such as beta blockers and ACE inhibitors, the number of patients living with heart failure continues to increase, and many of these patients will require advanced heart failure treatment. Yet there remains a limited number of hearts available each year for transplant, typically about 3,500. That leaves a growing mismatch between the number of people who can get a transplant and the number of people who need it. Mechanical circulatory support is filling that gap.

At this point in time, a transplant is still the best long-term solution for someone with end stage heart failure, says Banerjee. But the gap is closing. At Stanford, about 25 percent or more of end stage heart failure patients are getting LVADs as a bridge to transplant. In 2011, Stanford surgeons implanted more LVADs than hearts for the very first time in the program's history, and that trend is likely to continue.  

"There hasn't been a big change in transplant survival over the past two decades," says Banerjee. "But the technology and survival rate with mechanical circulatory support is improving exponentially.”

By Grace Hammerstrom