CHICAGO -- May 16, 2017 -- Left atrial appendage closure (LAAC) with an implantable device was successful in reducing the risk of stroke in patients with non-valvular atrial fibrillation (AF), with or without contraindication to oral anticoagulation, according to a study presented here at the 38th Annual Scientific Sessions of the Heart Rhythm Society (HRS).
“The device is a permanent implant designed to close the left atrial appendage in the heart in an effort to reduce the risk of stroke,” explained Lucas V. A. Boersma, MD, St. Antonius Ziekenhuis Hospital, Nieuwegein, the Netherlands.
The researchers examined data from 1,025 patients with non-valvular AF (mean age, 73 years) who had the WATCHMAN device implanted.
There was implant success in 98.5% of patients and 91% of active patients had been followed for at least 11 months.
The majority of patients (~73%) were not taking anticoagulants because of a history of major bleeding.
Co-morbidities were common in the study population and included diabetes, hypertension, congestive heart failure, and a history of haemorrhagic and ischaemic stroke.
“The expected stroke rate in this population is 7.2% and the actual stroke rate was 1.2%, giving us a relative risk reduction of 84%,” said Dr. Boersma.
Similarly, the implant reduced the risk of bleeding in patients. Thrombus of the device developed in 27 patients, and it occurred regardless of use of anticoagulants.
“One of the concerns may be the development of device thrombus,” said Dr. Boersma. “We did not find a correlation between patients having thrombus and the lack of use of anticoagulant medications.”
The 1-year mortality was 9.8%, but Dr. Boersma said the mortality was not attributable to the implantation of the device but rather the health status of the patients.
Funding for this study was provided by Boston Scientific Corporation.
[Presentation title: EWOLUTION Trial: 1-Year Efficacy and Safety of Left Atrial Appendage Closure With WATCHMAN in Patients With or Without Contraindication to Oral Anticoagulation. Abstract C-LBCT02-03]