AtriCure, a developer of solutions to treat atrial fibrillation (Afib), has announced the US Food and Drug Administration’s (FDA) approval to begin enrollment in a clinical study of its AtriClip left atrial appendage exclusion system.

The study will evaluate the use of the AtriClip device to prevent stroke in patients with Afib.

The feasibility study will enroll Afib patients at seven medical centers across the country.

The study will focus on patients with risk factors that place them at significant risk of stroke as well as substantial bleeding risks that contraindicate them for anticoagulation therapy. Research suggests that up to 40% of patients are unable to take oral anticoagulants due to excessive risk of bleeding.

Patients with Afib have a 500% increased risk of stroke over the general public. Afib related strokes are associated with higher morbidity and mortality than non-Afib related strokes.

Since the left atrial appendage (LAA), a muscular pouch attached to the heart, has been found to be the source of approximately 90% of thrombi in Afib patients evaluated after a confirmed stroke, this study will focus on complete and permanent mechanical closure of the LAA.

During the feasibility study, patients will undergo a minimally invasive surgical procedure. Utilizing small incisions in the chest wall surgeons will place the AtriClip device directly onto the base of the LAA while the heart is still beating.

Complete exclusion of the LAA is confirmed during the procedure using echo graphic imaging. Three months following the procedure, a computerized tomography (CT) scan will be performed to re-confirm complete and permanent LAA exclusion on all patients.

The AtriClip LAA exclusion system is indicated for the occlusion of the left atrial appendage, under direct visualization, in conjunction with other open cardiac surgical procedures.

AtriCure received FDA 510(k) clearance for the AtriClip device in June 2010 based upon the successful results of the EXCLUDE trial.

In this study, complete and permanent exclusion of the LAA was confirmed in 98.4% of patients by a three month post procedure CT scan with zero complications or adverse events.

AtriCure president and CEO Michael Carrel noted the stroke feasibility IDE study is significant because it is the first of its kind to focus entirely on a group of untreated and undertreated Afib patients that may benefit the most from total and permanent exclusion of their left atrial appendage.

"This study is one of three FDA trials that AtriCure is currently running as part of our strategy to be the leader in developing proven and effective solutions for the worldwide Afib epidemic," Carrel added.

Since launch, more than 25,000 AtriClips have been implanted worldwide.