Watchman Ups Quality of Life vs Chronic Warfarin in Nonvalvular AF: PROTECT AF

February 28, 2013

WASHINGTON, DC — Quality-of-life scores were "modestly" but significantly better at one year in patients with atrial fibrillation (AF) if they received the Watchman (AtriTech/Boston Scientific) device instead of chronic warfarin, in a follow-up analysis from one of the device's major clinical trials [1]. The Watchman is a percutaneously delivered left atrial appendage (LAA) closure implant designed to reduce or eliminate the need for oral anticoagulation in nonvalvular AF.

"The improvements were mainly in the area of physical functioning and were seen in both warfarin naive and not–warfarin-naive patients treated with LAA closure," write the authors of the PROTECT AF trial analysis, led by Dr Oluseun Alli (University of Alabama, Birmingham).

Patients randomized to warfarin showed declines in health-related quality of life, which "reflects subjective impairment in general well-being caused by individual aspects of pain and psychological, emotional, and physical disturbances," in this case related to any "burdens or side effects" of warfarin management. The group published their findings online February 26, 2013 in the Journal of the American College of Cardiology.

Watchman Also Looks for Closure

In the >700-patient PROTECT-AF trial, Watchman LAA closure was noninferior to chronic warfarin with respect to the primary efficacy end point of stroke, CV death, or systemic embolism at >1000 patient-years of follow-up. But it also showed a significantly greater risk of the primary safety end point, which included major bleeding, pericardial effusion, and device embolization.

Based primarily on PROTECT-AF, an FDA advisory panel in 2009 voted 7 to 5 to recommend approval of the Watchman, but the decision came with strings attached, designed to boost its safety and efficacy in practice. Almost a year later, the agency announced its refusal to make a decision on the device pending further safety and effectiveness data--all as reported by heartwire .

In response, the randomized PREVAIL trial, pitting the Watchman against warfarin management in paroxysmal, persistent, or permanent nonvalvular AF and with a target enrollment of 475 patients, was launched in November, 2010. Entry criteria include a CHADS2 score of at least 2 or a score of 1 in the presence of additional stroke risk factors including advanced age plus CAD, heart failure (up to NYHA class 3), or diabetes. Primary results are scheduled for presentation next month at the American College of Cardiology 2013 Scientific Sessions.

Modest Boost in Quality of Life

In the current analysis of baseline and 12-month responses to the SF-12 (version 2) survey, which included 361 Watchman patients and 186 who received warfarin (randomization had been 2:1), device patients showed a 34% better improvement in physical scores (p=0.01) and 50% better improvement in mental-health scores (p=0.06). They showed significantly better results also for physical functioning (p=0.0005) and physical role limitation (p=0.002).

The Watchman advantage was especially pronounced among patients who had never been on warfarin before (p=0.0004), but the authors caution against making too much of a subgroup analysis.

Reassured and Empowered

Alli et al propose potential explanations for the improved quality-of-life scores in patients who received the Watchman, who had been informed about their new device, their disorder, and the associated risks.

They "are reassured during follow-up that the device is working" and feel "empowered in a sense to be more active and behave in that way. The patients on warfarin, on the other hand, continue to have the blood tests and the dietary issues that we talk to them about and the bleeding hazard, and so they may restrict their activities more," they speculate.

"More important in the warfarin-naive patients, avoiding the aforementioned issues with anticoagulation with warfarin may lead to improved quality of life in these patients."

Alli had no disclosures; disclosures for the coauthors are listed in the paper.