Emory Healthcare currently is recruiting participants for a study to evaluate the safety and effectiveness of the Watchman Left Atrial Appendage System, designed to prevent life-threatening blood clots in patients suffering from atrial fibrillation.
Atrial fibrillation is a heart condition in which the upper chambers of the heart beat much more rapidly than normal. This often causes blood to stagnate and form clots in an area of the heart called the left atrial appendage -- which is a small, sac-like pouch located near the top of the organ. As a result of this condition, patients are usually prescribed a powerful blood thinner, such as Coumadin.
While blood-thinning medications are effective in preventing strokes, they require frequent monitoring to ensure proper levels. Too much blood thinner can be dangerous, and too little is ineffective. Patients taking blood thinners also may find that they bruise easily, and they may be at risk for bleeding.
According to Peter Block, M.D., professor of internal medicine in Emory University School of Medicine and the study's principal investigator, the trial involves a minimally invasive procedure to implant an umbrella-shaped mesh device in the opening of the left atrial appendage. The body soon begins to form tissue over the implant, permanently closing off the appendage and eliminating the risk of forming blood clots there.
"Through the Watchman study, we are hoping to find a way for individuals who suffer from atrial fibrillation to enjoy a much better quality of life, free from the risks and concerns that come with use of powerful blood thinning medications," says Block. "More than 5 million people in the United States suffer from atrial fibrillation, and there are more than 600,000 strokes each year. This device may be a way to improve lives and minimize or eliminate the risk of stroke as a result of atrial fibrillation."
As part of the study, participants will either receive blood thinner only, or will have the Watchman device implanted. The implantation procedure takes approximately 90 minutes. During the process, a physician makes a needle puncture in the groin and inserts a cardiac catheter. The collapsed Watchman device is attached to the end of a delivery catheter. Once the device is in place it is opened, forming a covering over the opening of the appendage. The delivery catheter is detached and removed. Patients usually go home the following day.
Candidates will be completely evaluated for the study based on a number of physical criteria, but general participation guidelines include:
- Evidence of persistent atrial fibrillation
- Ability either to stay on or get off Coumadin
- No history of heart failure
Those candidates who receive the device will remain on Coumadin for 45 days after the procedure. A follow-up exam tranesophogeal echo will be performed to gauge the effectiveness of the device and whether the appendage has fully closed. If there is no blood flowing around the device, Coumadin will be stopped and patients will be started on Plavix for five months. If there is still blood flowing around the device, however, patients will remain on Coumadin for an additional three months. All patients are expected to be removed completely from Coumadin within six months.
The Watchman clinical trial is being conducted at both Emory University Hospital and Emory Crawford Long Hospital. For more information, please call 404-712-7667.