The trial consists of two US investigational device exemption (IDE) studies evaluating the safety and effectiveness of the Medtronic Cardioblate Surgical Ablation System as a concomitant treatment for permanent and persistent atrial fibrillation (AF).

The Cardioblate System (BP2, LP, Pen, XL Pen, Generator) is currently cleared by the FDA under a 510(K) for the ablation of cardiac tissue. It is not approved by the FDA for the treatment of AF, and was not yet determined for treatment of AF is safe or effective.

According to Medtronic, CURE-AF will enroll a total of 150 patients at 15 US medical centers. Enrollment in the study of 75 patients with permanent AF is completed, and enrollment in the study of 75 patients with persistent AF is expected to be completed in the next several months.

CURE-AF investigates surgical tissue ablation with the Cardioblate system as a treatment for AF when conducted in conjunction with another open-heart operation, such as surgical valve repair or coronary artery bypass grafting (CABG). During the ablation procedure, surgeons use irrigated radiofrequency energy from the Cardioblate system to create a pattern of lesions on the heart muscle. The lesions are created to block the irregular electrical signals of the heart that cause AF.

Following analysis of six months of follow-up data in the permanent AF study and nine-month data in the persistent AF study, Medtronic anticipates submitting applications to the FDA in 2011 for approval of the Cardioblate system for two separate indications: permanent AF and persistent AF.

The primary endpoint for CURE-AF is clinically significant freedom from AF over a 24-hour period in patients off anti-arrhythmic drugs assessed at six months for the study of permanent AF and at nine months for the study of persistent AF. The safety endpoint for both studies is a composite of acute major adverse event (MAE) rate that is equal to or better than published results using other similar procedures.

Thoralf Sundt, a primary investigator of CURE-AF trial and a cardiothoracic surgeon at the Mayo Clinic in Rochester said: “Despite the frequency with which atrial fibrillation is confronted by cardiologists and cardiac surgeons, and the frequency of procedures performed to treat the condition, there is little evidence based on rigorous clinical studies to support one approach or another.”