HeartMate XVE left ventricular assist device

Sep 28 2005

Nine years ago this week, a team of University of Michigan doctors gave a dying heart patient a second chance at life by implanting a high-tech pump in his chest. The high-risk procedure was the first in Michigan performed using a new blood-pumping device called a HeartMate XVE left ventricular assist device, which helped the patient live until he received a heart transplant five weeks later.

Today, an improved version of that same life-saving technology, and similar devices, have helped more than 175 U-M patients and thousands of Americans with failing hearts. The U-M team has implanted more HeartMate devices than almost any other hospital in the country. And many more patients will be helped as continuing progress is made with the technology, and as doctors and patients become more familiar with its life-saving benefits.

The size of the current HeartMate XVE may not fit inside the bodies of some heart failure patients, particularly women. That’s why the U-M team is among the first in the United States to test the next generation of the technology. Already, seven patients have received the new, smaller and quieter implant, called HeartMate II left ventricular assist system, at U-M as part of a national research study. Other devices are also in testing at U-M.

“The technology has significantly improved, so that over the past five years we’ve been able to apply it to more patients with end-stage heart failure,” says Francis Pagani, M.D., Ph.D., an associate professor of cardiac surgery at the U-M who is co-director, along with cardiologist Keith Aaronson, M.D., of the Heart Transplant Program and the Center for Circulatory Support at the U-M Cardiovascular Center.

“Heart transplants, although a very effective therapy, are available only to a very small number of end-stage heart failure patients because of a shortage of donor organs,” Pagani says. “HeartMate gives us the ability to treat many others.”

In fact, he says, while his first HeartMate patient received the implant as a last-chance way to stay alive until a donor heart could be found, many of today’s patients get the device as a long-term or “destination” therapy, because they don’t qualify for a heart transplant and have just a few months to live.

The first destination-therapy HeartMate patient at U-M, Thomas Mator, is alive and well today - more than five years after he received his first implant. Mator, age 71 and an active grandfather and golfer, agreed to be the first patient at U-M in the study that tested HeartMate’s ability to keep patients alive over the long term.

Mator had suffered a heart attack on a golf course - but ignored the symptoms until he had finished playing the next nine holes and his son insisted he go to the emergency room. The damage his heart suffered put him into heart failure. Many medications, and lots of hospital stays, kept him going for a while. But finally, his doctor was out of options, and recommended U-M.

“We made an appointment and I went over there and they showed me this enormous, big pump,” Mator recalls. “It looked like a water pump out of a Ford pickup truck and they said they were going to put it in my belly and I said, ‘uh-uh.’ Not me.” But realizing that he wasn’t eligible for a heart transplant, that his medicines weren’t working and he could die within months, Mator learned more about the HeartMate study, and agreed to take part.

His surgery went well, and he soon returned to golfing, traveling to Florida and fixing things around the house and under the hood of his car. He’s had his HeartMate repaired or replaced several times, and follows careful instructions for keeping its batteries charged, staying active and eating healthy. Whenever he travels, he makes sure to note where the nearest HeartMate hospital is.

And in the five years since his operation, Mator has become an ambassador for U-M’s HeartMate program, meeting with new patients in the hospital and helping raise awareness of the technology. “I’m glad that this device came along when it did,” he says. “I feel extremely fortunate that I came around at the right time. It was almost the only option for me at the time.”

Pagani notes that there are perhaps 10,000 to 30,000 patients like Mator around the U.S. - men and women whose hearts can’t pump enough blood because their heart muscle was severely damaged by a heart attack, infection, years of high blood pressure, irregular heart rhythm, or another cause.

In the early stages of heart failure, patients can take medicines that help keep their heart pumping reasonably well, although many patients have to limit their physical activity and get tired and short of breath easily. They often must stop working outside the home and get help with everyday tasks.

But over time, the remaining healthy heart muscle can’t keep up with the tough job of squeezing hard enough to get blood to the entire body. It gets overworked, and stretches out, which in fact makes pumping harder. Less blood gets to the kidneys and other organs, damaging them and harming their ability to serve their function.

Eventually, despite taking dozens of pills every day, patients often wind up in the hospital with fluid buildup and other problems. These patients are in what is called end-stage heart failure, and are often very disabled. More than 52,000 of them die each year. To save their lives, heart transplants or HeartMates as a short-term or long-term solution, are the only option.

“The HeartMate device is designed to replace some of the pumping action of the heart, mainly the chamber called the left ventricle, which is the main pumping chamber of the heart,” he explains. “It pumps a normal amount of blood to the body, restoring the normal flow, helping the kidneys improve their function, and overall improving the patient’s well-being.” In general, devices like HeartMate are called LVADs, for left-ventricle assist devices.

For patients who are eligible for a heart transplant, Pagani and others have shown that the HeartMate helps improve their overall condition and in fact increases the chances that they’ll withstand the transplant operation and do well after it.

Although not every end-stage heart failure patient is a candidate for a HeartMate, and the device and operation cost tens of thousands of dollars, Pagani says that Medicare and other insurance plans increasingly will approve patients for the device. In fact, there’s growing evidence that having a HeartMate implanted may be more cost-effective over the long run for some patients than staying on medications and suffering crises that require a hospital stay. And quality of life is certainly better.

New Medicare insurance payment guidelines for LVAD follow-up care that take effect October 1 will help more hospitals afford the cost of offering HeartMate as an option for heart failure patients.

But U-M’s extensive experience in implanting the devices and caring for patients who have them puts Pagani and his colleagues at the forefront of helping patients have a successful outcome. That level of experience ties in nicely with the 21-year history of heart transplants at the U-M.

Meanwhile, the U-M is offering selected patients the opportunity to try the new HeartMate II, which is experimental but has many advantages over the FDA-approved HeartMate XVE device. Because HeartMate II has only one moving part and no reservoir for blood, and pumps blood continuously instead of in pulses, it is much smaller than the device that Mator compared to a Ford pickup water pump. That means it can fit inside the abdomen of many more patients. It’s also quieter; the original battery-operated HeartMate makes a whooshing and clicking sound every time it pumps.

The clinical trial of HeartMate II is still seeking patients, who can be candidates for a heart transplants who need temporary help, or seeking HeartMate as a “destination” therapy for long-term use. Patients in the destination therapy part of the trial must agree to be implanted with either a regular HeartMate or an experimental HeartMate II, depending on a random assignment, unless their bodies are too small for a the HeartMate XVE.

Other patients who are waiting for a transplant may qualify for the clinical trial of another small and experimental LVAD implant, the DeBakey VAD. It is available for both adults and children.

And more advances are on the way, says Pagani. “The devices today are much smaller and a marked improvement over the first generation. But there’s a third generation of LVAD devices now in experimental animal testing that will be coming to clinical trials within a year in the U.S. They may be potentially very durable, lasting 10 to 15 years. So the technology advancements continue.