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Study of atrial fibrillation needs participants

- By Tracie White

Paul Wang

Paul Wang

Researchers at the Stanford University School of Medicine are seeking participants for a study examining the effectiveness of a device that uses laser light technology to burn tissue in the heart as a treatment for a condition known as atrial fibrillation.

Atrial fibrillation, or a-fib, is a type of heart arrhythmia that affects 2.2 million Americans. It occurs when the upper chambers of the heart, called the atria, beat irregularly, leading to poor blood flow to the rest of the body. Patients with a-fib may be at an increased risk for strokes. A-fib may result in symptoms of palpitations, racing heart, shortness of breath and fatigue.

The first line of treatment for patients that are symptomatic with a-fib is usually medications to either restore normal rhythm or to control the heart rate. If these treatments fail, patients may require other treatments, such as catheter ablation. During catheter ablation, energy is sent into the heart through a catheter (a thin, flexible tube) to destroy small areas of heart tissue where abnormal heartbeats may arise.

Stanford will be one of up to 25 U.S. sites participating in the phase-3 trial, which is a safety and efficacy study looking at the performance of a laser-ablation catheter method compared with the standard radiofrequency-ablation catheter. The CardioFocus Endoscopic Ablation System with Adaptive Contact, or HeartLight system, differs from the prevalent method in that it delivers an arc of light energy instead of the more commonly used radiofrequency energy to heat the heart tissue during an ablation. Another feature of the system is the presence of an endoscope on the catheter, allowing electrophysiologists to see the tissue they wish to ablate. CardioFocus Inc., a company based in Marlborough, Mass., is the lead sponsor of the trial.

The device has been approved for use in Europe and is now being tested in the United States. The trial will compare the HeartLight system against the NaviStar system-guided Thermocool catheter in a randomized trial of an estimated 350 patients nationwide. The latter device is produced by Biosense Webster, a Johnson & Johnson company.

Paul Wang, MD, professor of cardiovascular medicine, is the principal investigator at the Stanford site. Stanford is recruiting about 20 participants for the study. For more information or to participate in the trial, call Linda Norton at (650) 725-5597.

Stanford Medicine integrates research, medical education and health care at its three institutions - Stanford School of Medicine, Stanford Health Care, and Stanford Children's Health. For more information, please visit the Office of Communications website at

2022 ISSUE 1

Understanding the world within us

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