CardioFocus, Inc., the manufacturer and developer of the HeartLight Endoscopic Ablation System (EAS) for the treatment of atrial fibrillation (AF), announced that its Premarket Approval (PMA) application was filed and has been accepted for review by the US Food and Drug Administration (FDA).

The accepted PMA application includes safety and effectiveness data from the company's multi-center HeartLight Pivotal Clinical Trial, a randomized, controlled study in which a total of 353 patients were treated at 19 leading arrhythmia centres across the United States. HeartLight Endoscopic Ablation System is a unique catheter ablation technology designed for the treatment of atrial fibrillation, the most common heart arrhythmia; it incorporates an endoscope to provide physicians with the capacity to see within the heart, and for the first time, visually direct the application of laser energy to achieve durable pulmonary vein isolation.

In addition, new original research from the HeartLight Pivotal Trial was published online ahead of print in the September 22 issue of the Journal of the American College of Cardiology (JACC). The article entitled, "Pulmonary Vein Isolation using the Visually-Guided Laser Balloon: a Prospective, Multicenter, and Randomized Comparison to Standard Radiofrequency Ablation" is authored by Srinivas Dukkipati, MD, et.al., from the Icahn School of Medicine at Mount Sinai, New York. The authors concluded, "In this multicenter randomized controlled study, HeartLight ablation was non-inferior to standard irrigated RF ablation in terms of the primary efficacy and safety endpoints."

The authors wrote, "Evaluation of operator learning-curve effects demonstrated that with increased operator experience, there was a significant improvement in fluoroscopy time and non-significant trends to improvement in procedure time, efficacy, and safety. The findings of this study are encouraging, given the relative lack of operator experience with HeartLight and a study protocol that tended to favour RF ablation due to the ability to perform ancillary ablation in the index procedure and redo procedures during the blanking period, which were not permitted in the HeartLight arm." Because the results of the HeartLight study have not yet been reviewed by the FDA they are to be considered preliminary.

The topline data from the HeartLight US Pivotal Trial were first announced at the Heart Rhythm Society (HRS) 2015 Annual Meeting on May 15, 2015, as presented by Vivek Y. Reddy, MD during a late-breaking clinical trial session.

Dr. Vivek Y. Reddy, senior author, co-principal investigator of the HeartLight US pivotal trial and professor of medicine and director of Cardiac Arrhythmia Services at the Mount Sinai School of Medicine, commented, "These results further demonstrate that a group of physicians largely new to the HeartLight technique can equal their outcomes with the control arm device by using the HeartLight System. Importantly, these results were obtained early in the HeartLight learning curve from veteran radiofrequency (RF) catheter ablation practitioners with extensive experience with the control arm device. Given that this was the first time these physicians were performing treatments using endoscopic guidance, without the guidance of local electrograms, this is really exciting; as a cardiologist, this is in fact the first time since surgical training that we can actually see what we are ablating inside the heart."

In an editorial accompanying the JACC article, entitled "Catheter Ablation of Atrial Fibrillation: Advent of Second-Generation Technologies," independent authors Eric Buch, MD, clinical instructor of medicine and Kalyanam Shivkumar, MD, PhD, director, UCLA Cardiac Arrhythmia Center & EP Programmes, both at the David Geffen School of Medicine at University of California, Los Angeles (UCLA), and not affiliated with the HeartLight trial, observed, "In theory, this technology has distinct advantages over both point-by-point ablation and the cryoballoon catheter. It offers stable catheter position and contiguous lesions like other balloon-based technologies, along with ability to selectively titrate energy to each part of the circumferential lesion set like point-by-point RF ablation. In addition, the laser balloon diameter can be changed dynamically to suit each PV antrum, and this is the first ablation technology to allow the operator to directly visualise tissue changes during ablation. However, theoretical advantages notwithstanding, the value of any ablation technology derives from its clinical results The early experience is promising, and HeartLight provides another piece of evidence that the days of point-by-point ablation for pulmonary vein isolation are numbered."

The US clinical trial results add to the large body of clinical evidence, which includes nearly two dozen independent studies, supporting the CardioFocus HeartLight Endoscopic Ablation System. Several EU single-center studies have been published reporting high rates of freedom from AF recurrence measured one year after the performance of a single ablation procedure using the CardioFocus endoscopically guided laser catheter. To date, more than 3,000 patients worldwide have been treated using the CardioFocus HeartLight System.

Stephen Sagon, president of CardioFocus, commented, "Publication of these data from our US pivotal trial of HeartLight in the JACC, one of the most prestigious and well-read cardiology peer-reviewed journals, not only provides us with comprehensive verification of the quality and thoroughness of our trial but also serves as tremendous validation by the medical community of the clinical outcomes showing HeartLight met both primary efficacy and safety endpoints and demonstrated a low learning curve for physicians. Equally, we are very excited to have our PMA application accepted for review by the FDA and look forward to providing an update on anticipated timing for FDA response regarding potential approval."