High implant success rate forWATCHMAN LAAC device derived from EWOLUTION registry evaluation.- Boston Scientific

Data confirmed that the WATCHMAN device had a high implant success rate and was effective in stroke reduction for patients with non-valvular atrial fibrillation (AF), including those patients deemed unsuitable for oral anticoagulation.

The prospective, single-arm, multicenter EWOLUTION registry evaluated 1,025 patients with non-valvular AF who have a high risk for stroke and systemic embolism. At one year post implantation of the device, the results demonstrated an 84 percent reduction in the annual stroke rate (1.1 vs 7.2/100 pt-years) as compared to predicted rates of untreated patients with similar risk profile and a reduction of 48 percent in the annual rate of major bleeding (2.6 vs 5.0/100 pt-years) as compared to predicted rates for patients treated with warfarin. In the study, patients were enrolled at 47 centers throughout Europe, Russia and the Middle East. More than 70 percent of the patients were deemed unsuitable for short or long-term anticoagulation at the time of WATCHMAN implantation.

Transient ischemic attacks, ischemic stroke, vascular disease and a history of major bleeding were present in approximately half of the patients. Additional EWOLUTION data will be presented on May 18 at the annual EuroPCR Scientific Congress in Paris.

Comment:The WATCHMAN device was CE-marked in 2005 to prevent thrombus embolization from the left atrial appendage and reduce the risk of life-threatening bleeding events in patients with non-valvular AF who are eligible for anticoagulation therapy, and in 2012 the CE Mark indication was expanded to include those who have a contraindication to anticoagulation therapy. In 2015, the device received FDA approval for patients with non-valvular AF who are at high stroke risk, suitable for warfarin and are seeking an alternative to long-term warfarin therapy. The Centers for Medicare and Medicaid Services (CMS) began covering percutaneous LAAC therapy for Medicare beneficiaries in February 2016 when patients meet the specific criteria outlined in the agency's final National Coverage Determination (NCD)..