November 30, 2009

The Heart of the Matter

Just before the annual deluge of holiday visitors began inundating the Magic Kingdom, over 20,000 people gathered in Orlando, Florida to attend the American Heart Association annual meeting. At one late-breaking scientific session, Dr. Joseph Rogers, a Duke University cardiologist, presented the results of a study of a nifty new cardiac device, the HeartMate II (to distinguish it from its predecessor, HeartMate I, also known as HeartMate XVE). This remarkable 390-gram contraption is the next best thing to a heart transplant for patients with severe heart failure. It is a “ventricular assist device,” (VAD) implanted in the abdomen, hooked up to the heart to propel blood through a failing ventricle, and powered by an external generator. The study, published the very same day in the online version of the New England Journal of Medicine, showed that patients with the new device lived longer and better, with fewer complications, than those who got the earlier variety.

Just six years ago, the Centers for Medicare and Medicaid Services (CMS) approved use of the HeartMate I in Medicare patients as “destination” or definitive treatment of severe heart failure. Based on the results of a 2001 study, the REMATCH (Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure) trial, CMS concluded that the device was “reasonable and necessary” for the treatment of advanced heart failure and therefore, as required by its 1965 Congressional mandate, agreed to pay for implantation of the device.

Physicians, however, were not convinced the device was reasonable or necessary. In fact, the number of patients receiving a ventricular assist device has fallen every year since CMS approved its use. Between March, 2006 and June, 2009, a total of only 1664 HeartMate I’s were implanted (just under 500 per year) and 90% of them were used as “bridge to transplant,” that is to tide patients over until a heart became available for transplant, rather than as “destination therapy,” or permanent treatment. Physicians evidently were not impressed by the data that patients who had a ventricular assist device lived longer than those receiving “maximal medical therapy.” Even with the device, one-year mortality remained high at 48% and two-year mortality at 77%. Moreover, HeartMate I recipients were at risk of stroke, infection, and device malfunction.

Will physicians be more enthusiastic about the new HeartMate II? It is smaller—small enough to fit into a woman, unlike the earlier version. It uses a continuous rotary system rather than a pulsatile mechanism, which means it’s quieter and more durable. And the new device is clearly superior to the old one—the randomized study reported in Orlando found that 46% of those with the new device were alive after 2 years without having sustained a debilitating stroke or required replacement of the device, compared to 11% of those who got the original model. Quality of life was also improved, with recipients of the new HeartMate able to walk further and do more for themselves.

Are these results good enough? They will almost surely be good enough for the Food and Drug Administration to approve use of the device as destination therapy and for Medicare to follow suit by approving reimbursement in Medicare patients—currently Medicare pays an average of $177,000 for a hospitalization in which a ventricular assist device is inserted. Whether physicians will regard the new pump as ready for prime time remains to be seen.

The deeper question is whether we should be putting more and more resources into shoring up failing hearts in patients near the end of life or whether, instead, we should concentrate on palliative care for patients dying of heart failure and on prevention to avoid the development of heart failure in the first place.

Palliative care is an effective, well-regarded approach to end stage heart failure. It focuses on comfort and on supporting patients and their families as the end draws near and may involve enrollment in hospice. Individuals whose heart cannot pump properly repeatedly suffer from fluid backing up into their lungs, swelling their legs, and filling their abdomen, causing shortness of breath, difficulty walking, and fatigue. Instead of hospitalizing these patients, often transferring them to the Intensive Care Unit where they may be attached to a ventilator that forces oxygen into their lungs and put on an intravenous drip to try to stimulate the heart to contract more forcefully, palliative care strives to keep them home. At home they use oxygen and medication such as morphine to help them breathe. Interestingly, the studies of the left ventricular assist device compare patients receiving one particular device to those getting another type (the new study) or patients receiving a device to patients receiving “maximal medical therapy” (the earlier study), but never compare patients receiving a device to those getting palliative care.

Prevention makes a lot of sense in the case of heart failure. Heart failure is the leading cause of hospitalization in individuals over age 65. Americans have a 20% life time risk of developing the condition and treatment costs the US upwards of $30 billion per year. But we know what causes the heart to fail: it is high blood pressure, diabetes, or coronary artery disease (which in turn is caused by some combination of high blood pressure, diabetes, high cholesterol and smoking). And every one of these predisposing conditions is treatable or preventable. While there are few good studies of what it would cost to institute a comprehensive set of measures to prevent heart failure, we do know that 82% of the cardiac events in one observational study, the Nurses Health Study, were attributable to diet and lifestyle issues. An Australian analysis suggests that the best way to prevent heart failure is by a combination of medical preventive strategies (proceeding patient by patient to assess risk factors and intervene to treat high blood pressure, diabetes, and high cholesterol) and public health strategies (using legislative and environmental approaches to promote a healthy lifestyle).

America has its heart set on the technological fix—the HeartMate II is the latest in a series of ingenious approaches to treating the chronic diseases afflicting older people. But its time to get to the heart of the matter, trying to prevent the major scourges that we have the knowhow to avoid, and palliating those who, despite our best efforts, are dying.