The first patient has been treated in the Boston Scientific Corporation clinical trial to evaluate the safety and effectiveness of the Blazer(R) Open-Irrigated Temperature Ablation Catheter in patients with symptomatic, drug refractory paroxysmal atrial fibrillation. This international, multi-center study will include up to 33 sites in the United States, Europe and Asia-Pacific, and as many as 472 patients. The results of the ZERO AF trial are expected to be used to support a U.S. Food and Drug Administration regulatory submission for a paroxysmal atrial fibrillation indication.

Atrial fibrillation is a disorder that disrupts the ability of the heart to beat regularly and pump blood efficiently. It affects approximately 15 million people worldwide and can lead to complications such as stroke or heart failure. Paroxysmal atrial fibrillation is a type of atrial fibrillation in which the irregular heartbeat starts up very quickly, stops spontaneously and abruptly returns to the normal rhythm resulting in patients feeling symptomatic.

Catheter ablation, a procedure in which localized electrical energy is delivered into the heart tissue aimed at restoring the continuous normal rhythm, is a common treatment for many heart rhythm disorders including paroxysmal atrial fibrillation. The Blazer Open-Irrigated Catheter is the latest addition to the extended families of Boston Scientific Blazer catheters. It is the company's first entry into the open-irrigated catheter segment and is approved for use in CE Mark countries and Canada.

The Blazer Open-Irrigated Catheter offers the Total Tip Cooling(TM) design, engineered to consistently cool the entire tip of the electrode during radiofrequency energy delivery.