close up of WATCHMAN FLX device with decorative teal overlay

Clinical trials

  

Active trials

CHAMPION‑AF

With over 400,000 patients implanted with the WATCHMAN platform, CHAMPION-AF extends Boston Scientific’s LAAC leadership by evaluating WATCHMAN FLX™ Left Atrial Appendage Closure Device as a safe and effective first-line option versus NOAC to reduce stroke risk.*

OPTION clinical trial

The OPTION clinical trial is a randomized controlled trial comparing the safety and effectiveness of left atrial appendage closure (LAAC) to oral anticoagulation (OAC) therapy for stroke protection in post-ablation patients with atrial fibrillation.

This study involves an investigational device called the WATCHMAN FLX™**.

Clinical trial results

PINNACLE FLX clinical study

The PINNACLE FLX US IDE Trial1 was designed to establish the Procedural Safety and LAA Closure Efficacy with the WATCHMAN FLX LAAC Device.

First three-year data from NCDR-LAAO Registry

The NCDR-LAAO Registry analysis is a review of the first three years and over 38,000 WATCHMAN implants.  This analysis, The NCDR Left Atrial Appendage Occlusion (LAAO) RegistryTM: Review of the First 3 Years, presented by Dr. James Freeman on March 29, 2020 at the ACC 2.0/WCC Virtual Experience. This analysis demonstrates that major in-hospital adverse event rates were in-line with those reported in the pivotal WATCHMAN device trials.

Learn more:

Freeman et al, The NCDR Left Atrial Appendage Occlusion (LAAO) Registry™: Review of the First 3 Years, JACC, March 2020

Long-term patient-level meta-analysis

Five year results from a patient-level meta-analysis of the totality of data available on the WATCHMAN Device, by Reddy, et al, has been published in the Journal of American College of Cardiology (JACC). This publication includes 5-year outcomes of PREVAIL, combined with the 5-year outcomes of PROTECT-AF, and demonstrated that LAAC with Watchman provided stroke reduction in non-valvular atrial fibrillation comparable to warfarin with additional reductions in major bleeding and mortality. 

Learn more:

Reddy VY, et al. JACC 2017; 70(24): 2964-2975.

Initial commercial experience data

Post-FDA Approval, Initial US Clinical Experience with WATCHMAN Left Atrial Appendage Closure for Stroke Prevention in Atrial Fibrillation

Initial US Clinical Experience evaluates the acute procedural performance and complication rates for all WATCHMAN cases performed in the US since FDA approval.

The authors conclude that despite a large fraction of previously-inexperienced operators, in the real-world post-FDA approval experience of WATCHMAN LAAC, procedural success was high and complication rates low.

Learn more:

Reddy VY, et al. JACC 2017; 69(3): 253-261.

CAP 2 Registry

The Continued Access to PREVAIL (CAP2) Registry is a multi-center prospective non-randomized study allowing continued access to the WATCHMAN Device, following the PREVAIL trial, during regulatory review of the pre-market application for the WATCHMAN Device. The primary objective of the CAP2 registry was to collect additional safety and effectiveness data on the WATCHMAN Device in patients with non-valvular atrial fibrillation who are deemed by their physicians to be suitable for warfarin therapy.

PREVAIL clinical trial

The goal of the PREVAIL trial was to assess the safety and efficacy of LAA closure for stroke risk reduction in patients with NVAF compared with long-term warfarin therapy.

The authors concluded that in this trial, LAA occlusion was non-inferior to warfarin for ischemic stroke risk reduction or SE >7 days’ post-procedure. Although non-inferiority was not achieved for overall efficacy, event rates were low and numerically comparable in both arms. Procedural safety was significantly improved. This trial provided additional data that LAA occlusion is a reasonable alternative to warfarin therapy for stroke risk reduction in patients with NVAF who do not have an absolute contraindication to short-term warfarin therapy.

Learn more:

Holmes DR Jr, Kar S, Price MJ, et al. Prospective randomized evaluation of the WATCHMAN Left Atrial Appendage Closure device in patients with atrial fibrillation versus long-term warfarin therapy: the PREVAIL Trial. J Am Coll Cardiol. 2014;64(1):1-12.

CAP registry

The Continued Access to PROTECT AF (CAP) registry was a multi-center prospective non-randomized study allowing continued access to the WATCHMAN Device, following the PROTECT AF trial, during regulatory review of the pre-market application for the WATCHMAN Device. 

The primary objective of the CAP registry was to collect additional safety and effectiveness data on the WATCHMAN Device in subjects with non-valvular atrial fibrillation who are deemed by their physicians to be suitable for warfarin therapy.

PROTECT AF clinical trial

The multicenter PROTECT AF study (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) was conducted to determine whether percutaneous left atrial appendage closure with a filter device (WATCHMAN) was non-inferior to warfarin for stroke risk reduction in atrial fibrillation.

In the Journal of the American Medical Association article (4-year results), the authors concluded that after 3.8 years of follow-up among patients with non-valvular AF at elevated risk for stroke, percutaneous LAA closure met criteria for both non-inferiority and superiority, compared with warfarin, for preventing the combined outcome of stroke, systemic embolism, and cardiovascular death, as well as superiority for cardiovascular and all-cause mortality.

Learn more:

Reddy VY, Sievert H, Halperin J, et al; for the PROTECT AF Steering Committee and Investigators. Percutaneous left atrial appendage closure vs warfarin for atrial fibrillation: a randomized clinical trial. JAMA. 2014;312(19):1988-1998. 

Pilot study

Meta-analyses confirmed that in cases of left atrial thrombus in non-rheumatic AF patients approximately 90% of them are in the left atrial appendage (LAA).  This study assessed the feasibility of implanting a device in the LAA in patients with atrial fibrillation (AF) to prevent thromboembolic stroke.

The authors concluded that preliminary data suggest LAA occlusion with the WATCHMAN System to be safe and feasible. 

Learn more:

Sick PB, Schuler G, Hauptmann KE, et al. Initial worldwide experience with the WATCHMAN Left Atrial Appendage System for stroke prevention in atrial fibrillation. J Am Col Cardiol. 2007;49(13):1490-1495.

WATCHMAN device

*WATCHMAN FLX is an FDA approved device being studied for an expanded indication as a first line therapy vs NOAC for NVAF patients. The use of WATCHMAN or WATCHMAN FLX as a first-line therapy for stroke risk reduction in NVAF patients is considered investigational.

**WATCHMAN FLX is an FDA approved device being studied for an expanded indication as a first line therapy vs NOAC for NVAF patients post-ablation. The use of WATCHMAN or WATCHMAN FLX as a first-line therapy for stroke risk reduction in NVAF patients post-ablation is considered investigational.

1.  Kar, S., et al, Primary Outcome Evaluation of the Next Generation LAAC Device: Results from the PINNACLE FLX Trial, Circulation, 2021.