Evaluation of the WATCHMAN Left Atrial Appendage (LAA) Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy

Boston Scientific Corporation407 enrolled

Overview

This was a prospective, randomized, multicenter study to provide additional information on the safety and efficacy of the WATCHMAN LAA Closure Technology. The purpose of the PREVAIL study was to confirm the efficacy endpoint as demonstrated in the PROTECT AF pivotal study and to further demonstrate that the WATCHMAN LAA Closure Technology is safe and effective in subjects with non-valvular atrial fibrillation who require anticoagulation therapy for potential thrombus formation.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

407

Conditions

Atrial Fibrillation Stroke

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Key Inclusion Criteria: * Paroxysmal, persistent or permanent non-valvular AF * Eligible for long-term warfarin therapy * Eligible to come off warfarin therapy * Calculated CHADS2 score of 2 or greater. Also patients with a CHADS2 score of 1 may be included if any of the following apply: * Female age 75 or older * Baseline LVEF ≥ 30 and \< 35% * Aged 65-74 and has diabetes or coronary artery disease * Aged 65 or greater and has congestive heart failure Key Exclusion Criteria: * Contraindicated/allergic to aspirin * Indicated for clopidogrel therapy or has taken clopidogrel within 7 days prior to enrollment * History of atrial septal repair or has an ASD/PFO device * Implanted mechanical valve prosthesis * NYHA Class IV CHF * Resting heart rate \> 110 bpm * Participated previously in the PROTECT AF or CAP Registry studies Key Echo Exclusion Criteria: * LVEF \< 30% * Existing pericardial effusion \> 2mm * High risk PFO * Significant mitral valve stenosis * Complex atheroma with mobile plaque of the descending aorta and/or aortic arch * Cardiac tumor

Locations (41)

Mercy Gilbert Medical Center

Gilbert, Arizona, United States

Arizona Heart Rhythm Research Center

Scottsdale, Arizona, United States

Foundation for Cardiovascular Medicine

La Jolla, California, United States

Scripps Green

La Jolla, California, United States

Cedars-Sinai Medical Center

Los Angeles, California, United States

Outcomes

Primary Outcomes

Primary Safety Endpoint (Device Group Only)

7-Day procedure rate of death, ischemic stroke, systemic embolism and complications requiring major cardiovascular or endovascular intervention.

Time frame: 7-Day

Composite of Stroke, Systemic Embolism, and Death (Cardiovascular and Unknown)

The endpoint was analyzed using a Bayesian piecewise exponential model with the historical priors based on data from the previous pivotal study PROTECT AF. This was a non-inferiority design with comparison of rate ratio of 18-month event rates of the Device and Control groups. The 18-month rate represents the probability of an event occurring within 18 months, and the 18-month rate ratio is a mean of the rate ratios. The primary endpoint was based on a calculation of the probability of events at 18 months but the statistical piecewise hazards model does not require the observation of any subjects out to 18-months.

Time frame: 18 month rate

Composite of Ischemic Stroke or Systemic Embolism

Composite of ischemic stroke or systemic embolism excluding events that occurred in the first 7 days following randomization

Time frame: Day 8 to 18-months