Study: Heart-assist device yields excellent survival

November 19, 2002

CHICAGO - An implanted pumping device that helps a failing heart may improve survival for desperately ill patients and allow them to go home from the hospital, a new study finds -- whether they're waiting for a heart transplant or aren't eligible for one.

And, as hospitals gain experience in determining who can be helped by the device, survival is rising while problems and hospital stays related to the device are dropping.

Those are the conclusions from a new six-year prospective study of 100 heart failure patients who received the implanted device, called a HeartMate, at the University of Michigan Health System. The study results will be presented Nov. 19 at the 75th Annual Scientific Sessions of the American Heart Association by Francis Pagani, M.D., the cardiac surgeon who leads the U-M HeartMate team.

UMHS has performed more HeartMate operations than all but two hospitals in the United States. This gives its team valuable experience in the selection, care and follow-up of those who receive the device -- improving the outlook for patients.

Now that HeartMate has been approved by the Food and Drug Administration for both patients awaiting a new heart, and those who can't tolerate a heart transplant, the UMHS team hopes to put that experience to work in even more patients. On Nov. 6, the FDA approved the device as a permanent option for patients who are too old or ill, or have too many other health conditions, to qualify for a heart transplant.

"We find that the use of this therapy results in excellent one-year survival that approaches that of heart transplantation," says Pagani, an associate professor of surgery who also leads the Heart Transplant Program at the U-M Cardiovascular Center. "And we saw good survival for those who used the device for more than a year, either while waiting for a new heart or as their destination therapy."

The HeartMate device is part of a class of technology known as LVADs, or left ventricular assist devices. LVADs don't replace the heart, but rather help do the job of the heart's main pumping chamber. Early HeartMates ran on a pneumatic air pump, but recent versions use an electric motor powered by a wearable battery pack.

In all, the 100 patients who got a HeartMate device at U-M between October 1996 and May 2002 lived a total of 9,241 days on the device -- more than 57 percent of them at home. As the team's experience grew, results improved: the 50 most recent patients lived 6,600 days with the device, 75 percent of the days at home. Eighty-two percent of the last 50 patients, and 58 percent of all patients, were able to go home.

Seventeen patients who received the HeartMate at UMHS died, nearly all within three weeks of receiving the device -- and nearly all because of circulatory system failure. This rate may have been related to the critically ill state of many patients just before they received their HeartMate implant; 45 percent had been on life support, a ventilator or temporary cardiac assist devices.

The median hospital stay immediately following the operation to implant a HeartMate was three weeks, and just under half of patients were readmitted at least once. But patients treated more recently had shorter hospital stays, and fewer days in the intensive care unit.

Problems with the device did occur, especially in earlier versions of the technology. But more than four-fifths of patients went six months without a major device failure. About half of patients who had the device for a full year, whether because no suitable heart had been found or because they were ineligible for a transplant, experienced a significant device failure, such as a pump stoppage or failure of the valve that lets blood into the device's pumping chamber.

In all, the prospects for HeartMate recipients have improved significantly as doctors at UMHS and other major centers gain experience in the overall management of these patients.

"Improvements in patient selection and follow-up care, along with trend toward implanting the device earlier in a patient's illness, have helped cut the death rate and length of post-implant hospital stays significantly," says Pagani.

According to the American Heart Association, 4.79 million Americans have congestive heart failure, a potentially lethal condition marked by progressive failure of the muscle that makes up the heart's pumping chambers. Heart failure can be brought on by the oxygen-depriving effects of a heart attack or by cardiomyopathy (heart muscle disease) caused by unknown factors; 41 percent of the 100 HeartMate patients at Michigan had this kind of "idiopathic" heart failure.

Heart transplants can save the lives of many heart failure patients, but the shortage of donated hearts means many patients die or grow too ill for a transplant before a suitable heart is found.

According to the Scientific Registry of Transplant Recipients, 4,106 people were on the waiting list for a heart transplant at the start of 2001, and 3,402 more were added during the year. A total of 2,202 heart transplants were performed during 2001, but 623 patients on the waiting list died and 139 patients deteriorated to the point that they became ineligible for transplant during the same time. By the end of 2001, 4,097 people were still waiting for a new heart.

LVADs offer a promising solution for many patients, Pagani says, though the technology can still be improved to reduce problems and to allow more patients to receive the device. Eighty percent of the patients in the UMHS study were men, mainly because the device's canteen-like size and shape means that it cannot be implanted in many women.

Pagani and his colleagues look forward to implanting HeartMate devices in many more patients as a "bridge" to transplant or as a permanent therapy. Because of their experience with LVAD therapy since the early days of HeartMate clinical trials, they also look forward to participating in clinical trials for the next-generation devices now in development.

In addition to Pagani, the study's authors are research coordinator Susan Wright, R.N., BSN, and cardiologists David Dyke, M.D., and Keith Aaronson, M.D., M.S., medical director of the U-M heart transplant program. Many of the patients were participants in clinical trials sponsored by HeartMate manufacturer Thoratec Corporation.

Note to editors: Several patients who received HeartMates at UMHS are available for interviews. Call UMHS Public Relations, 734-764-2220.

Heart failure patients: For information on Heartmate therapy at UMHS, call 734-615-3323.
-end-


University of Michigan Health System

Related Heart Failure Articles from Brightsurf:

Top Science Tip Sheet on heart failure, heart muscle cells, heart attack and atrial fibrillation results
Newly discovered pathway may have potential for treating heart failure - New research model helps predict heart muscle cells' impact on heart function after injury - New mass spectrometry approach generates libraries of glycans in human heart tissue - Understanding heart damage after heart attack and treatment may provide clues for prevention - Understanding atrial fibrillation's effects on heart cells may help find treatments - New research may lead to therapy for heart failure caused by ICI cancer medication

Machining the heart: New predictor for helping to beat chronic heart failure
Researchers from Kanazawa University have used machine learning to predict which classes of chronic heart failure patients are most likely to experience heart failure death, and which are most likely to develop an arrhythmic death or sudden cardiac death.

Heart attacks, heart failure, stroke: COVID-19's dangerous cardiovascular complications
A new guide from emergency medicine doctors details the potentially deadly cardiovascular complications COVID-19 can cause.

Autoimmunity-associated heart dilation tied to heart-failure risk in type 1 diabetes
In people with type 1 diabetes without known cardiovascular disease, the presence of autoantibodies against heart muscle proteins was associated with cardiac magnetic resonance (CMR) imaging evidence of increased volume of the left ventricle (the heart's main pumping chamber), increased muscle mass, and reduced pumping function (ejection fraction), features that are associated with higher risk of failure in the general population

Transcendental Meditation prevents abnormal enlargement of the heart, reduces chronic heart failure
A randomized controlled study recently published in the Hypertension issue of Ethnicity & Disease found the Transcendental Meditation (TM) technique helps prevent abnormal enlargement of the heart compared to health education (HE) controls.

Beta blocker use identified as hospitalization risk factor in 'stiff heart' heart failure
A new study links the use of beta-blockers to heart failure hospitalizations among those with the common 'stiff heart' heart failure subtype.

Type 2 diabetes may affect heart structure and increase complications and death among heart failure patients of Asian ethnicity
The combination of heart failure and Type 2 diabetes can lead to structural changes in the heart, poorer quality of life and increased risk of death, according to a multi-country study in Asia.

Preventive drug therapy may increase right-sided heart failure risk in patients who receive heart devices
Patients treated preemptively with drugs to reduce the risk of right-sided heart failure after heart device implantation may experience the opposite effect and develop heart failure and post-operative bleeding more often than patients not receiving the drugs.

How the enzyme lipoxygenase drives heart failure after heart attacks
Heart failure after a heart attack is a global epidemic leading to heart failure pathology.

Novel heart pump shows superior outcomes in advanced heart failure
Severely ill patients with advanced heart failure who received a novel heart pump -- the HeartMate 3 left ventricular assist device (LVAD) -- suffered significantly fewer strokes, pump-related blood clots and bleeding episodes after two years, compared with similar patients who received an older, more established pump, according to research presented at the American College of Cardiology's 68th Annual Scientific Session.

Read More: Heart Failure News and Heart Failure Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.