Alternative to Warfarin
The current most common treatment for stroke prevention in people with AF is a prescription for warfarin (Coumadin), an oral anticoagulant. However, there are several major drawbacks to warfarin therapy. An increased risk of serious bleeding means that warfarin may be contraindicated for some people, including older adults who are at high risk for falls. In other cases, warfarin may still be prescribed, but the risk of dangerous bleeding means that people may be advised to curtail activities they once enjoyed, such as skiing and other sports in which falls are common.
Another key disadvantage of warfarin is its narrow therapeutic window coupled with wide variability in how individual patients respond to the drug. It takes careful calibration to find the safe and effective dose for a particular patient, and monthly blood draws to monitor blood levels of the drug are required indefinitely. Warfarin also interacts with a number of prescription and over-the-counter medicines, such as antibiotics, salicylates, nonsteroidal anti-inflammatory drugs, beta-adrenergic blockers, diuretics, antidepressants, diabetes agents, and gastric acidity and peptic ulcer agents. Drug-drug interactions can be problematic for older adults, who are often taking multiple medications. In addition, certain foods interfere with how warfarin works, which necessitates some dietary restrictions, such as limiting green leafy vegetables, Brussels sprouts, and broccoli.
Warfarin therapy is contraindicated for a sizable minority of patients with AF. Even when there is no clear contraindication to its use, the drug often is not prescribed. And when it is prescribed, many patients take more or less than the optimal dose. Clearly, there is a pressing need for more options.
The Watchman device, designed to be a nonpharmacological alternative to warfarin, is a new option that researchers are now exploring. If the LAA is blocked off successfully, as it is in the large majority of cases, warfarin can be discontinued. Thus, one potential benefit of the Watchman is removing the side effects and lifestyle restrictions that go along with taking warfarin.
Minimally Invasive Procedure
The Watchman device is implanted with a catheter-based delivery system via a trans-septal approach; that is, by passing a catheter from the right into the left side of the heart. An access sheath and dilator are first advanced into the left atrium over a guide wire, and the access sheath is then further advanced into the LAA over a pigtail catheter. Finally, the Watchman is inserted into the access sheath and carefully guided into position, using TEE and fluoroscopy to verify positioning and stability. Once deployed, the device opens up like a parachute, creating a plug for the LAA.
The LAA closure procedure is performed under general anesthesia. It takes approximately an hour to perform—and the closure time is decreasing as surgical expertise increases. Patients typically stay in the hospital for one night. Walking is generally permitted the same night as the procedure, but heavy lifting is avoided for a week. After a week, most patients can resume their regular activities.
Studies have yet to be performed comparing the cost-effectiveness of the Watchman device with warfarin. Implantation of the Watchman is a one-time investment, while warfarin therapy is a continuous expense. However, any economic analysis would also need to factor in the cost of both treatment options, including medical follow-up and any complications.
In summary, the procedure to insert Watchman device is minimally invasive. In the first phase of the PROTECT AF trial, the device was as effective as warfarin for preventing stroke in AF patients. Our practice has one of the largest experience in Watchman implant procedure in the US. Watchman offers a new option for people with AF who are seeking an alternative to the risks of warfarin.