New Heart Implant May Help Prevent Stroke

By: Diana Barnes-Brown for Body1

A new heart implant device may help prevent stroke by preventing atrial fibrillation, a common type of irregular heartbeat that can increase the likelihood of blood clots forming in the heart.

Take Action

A-fib and Stroke Atrial fibrillation, or “a-fib” causes an estimated 120,000 strokes annually in the United States. Learning to recognize a-fib before it causes problems can save lives, and learning to recognize the symptoms of stroke can save valuable minutes and hours when it comes to treating these dangerous medical events effectively. Symptoms of a-fib: Heart palpitations Chest pain (angina) Fatigue and poor exercise tolerance Shortness of breath Lightheadedness and fainting Symptoms of stroke: Sudden weakness or numbness in face, arm, or body, especially one-sided weakness Sudden confusion or trouble speaking Sudden loss of coordination or balance Sudden severe headache with no known cause

Atrial fibrillation, known to doctors as “a-fib” is responsible for an estimated 120,000 strokes annually in the United States, due to its ability to cause blood clots in the heart and route them straight to the brain. Until now, the most successful way to prevent these clots was with the drug warfarin – but this drug is incompatible with many elements of a normal diet, as well as with a host of other medications.

Fortunately, thanks to an experimental new device called the Watchman, doctors and patients alike are hopeful about preventing blood clots related to a-fib while also cutting down on the need for warfarin regimens.

Dr. Steven Almany, the vice chief of cardiology at William Beaumont Hospital in Michigan, has implanted the Watchman device in many of his patients’ hearts. When interviewed by ABC News in late November 2006, he stated that he believes the device has the potential to “revolutionize” treatment for a-fib, which affects nearly three million people in the United States.

A-fib is the most common type of irregular heartbeat, and occurs more frequently among elderly patients. U.S. Census data indicates that through the 20th century, the population of persons age 65 or over had increased at nearly four times the rate of the overall population. As the general population aged, a-fib became a much more common complaint and a much more common cause of stroke. The strokes caused by a-fib also tend to be among the most severe: about one third of afflicted patients die, while another third suffer permanent disability.

A-fib is caused by a lack of synchronization between the pumping of the heart’s top and bottom chambers. The atria can speed up and quiver, causing blood to pool and clot inside of a pocket of the heart sometimes called the “heart’s bellybutton” because it is a vestigial structure left behind from the time of fetal development.

Traditionally the best way to prevent these clots was chemically with warfarin, but warfarin requires those who take it to stop use of – among other things – antidepressants, lipid-lowering medications, acetaminophen (the active ingredient in Tylenol), antifungal medications and NSAIDs, as well as avocado, cranberry juice, garlic, onion, mango, and soy products. Even if dietary and medication interaction precautions are observed, warfarin itself can cause side effects including hair loss, diarrhea, severe bleeding and gangrene. With medical and dietary limitations such as these, it’s no wonder that some patients balk at the prospect of depending on warfarin. Others find that they simply can’t remember how to take it safely.

The Watchman device, on the other hand, acts mechanically, by actually closing off the problematic pocket so that blood cannot pool and clot there. It is threaded into the body by way of the large vein that runs the length of the upper leg, and then up to the heart, where it is wedged into place to seal off the flap. Small hooks hold the device in place until heart tissue seals it into place, closing off the troublesome pocket. About six weeks after implantation, patients undergo heart scans to confirm that the pocket has closed completely, and if it has, they are taken off warfarin.

Currently, 250 patients are enrolled in Almany’s study designed to test the effects of the Watchman, and 97 percent have been able to stop their warfarin regimen. They still must be followed for two years, but so far the success rate looks promising. At the same time, the Watchman is not without risk. The very thin tissue of the flap the device blocks is susceptible to tearing as the device is hooked in place – and bleeding caused by such a tear could be life-threatening. Furthermore, despite warfarin’s many disadvantages, its success as a stroke fighter is proven.

While further research is clearly called for, if the results are positive, patients may soon be able to benefit from a far more palatable way of preventing life-threatening strokes.

Last updated: 23-Jul-07