nContact Surgical (Morrisville, North Carolina) reported the initiation of a feasibility clinical trial designed to evaluate the safety and efficacy of a combined surgical and catheter procedure, the convergent procedure, for the treatment of symptomatic paroxysmal atrial fibrillation (AF). This prospective, feasibility study will enroll patients at study sites across the U.S.

"We call it the convergent procedure because it really combines the best of surgical techniques with the best of the [electrophysiology] EP techniques," John Funkhouser, president/CEO of nContact, told Medical Device Daily.

The hope is that the combination procedure will allow the physicians to ultimately treat all AF patients in a single procedure, Funkhouser said.

"We designed this study to include paroxysmal patients with enlarged hearts, who historically have been more difficult to treat with catheter ablation in a single procedure," Funkhouser said. "The uniqueness of the convergent procedure is that lesions can be created on all areas of the heart through a closed chest endoscopic approach, without lung deflation, and while the heart is beating."

Funkhouser said the feasibility trial would enroll about 25 patients and five sites. Patient follow-ups will most likely be done at three, six and 12 months, he said. He said the trial would hopefully be followed by an investigational device exemption study.

The convergent procedure "creates a truly total solution for all patient types," Funkhouser said.

The study uses the nContact Numeris- AF Guided Coagulation System with VisiTrax along with a commercially available ablation catheter, Biosense Webster's (Diamond Bar, California) NaviStar ThermoCool catheter. The combination of devices creates a standard, bi-atrial lesion pattern to block electrical signals that cause AF. In addition, electrophysiologists have the capability to diagnostically ensure the lesion pattern is complete with pulmonary vein isolation, the company said.

"We look forward to investigating this collaborative, interdisciplinary approach for the treatment of atrial fibrillation in patients with larger atria," said Rodney Horton, MD, principal investigator at St. David's Medical Center (Austin, Texas).

Earlier this year the NaviStar ThermoCool and the EZ Steer ThermoCool Nav, produced by Biosense Webster, became the first ablation catheters to be FDA cleared to treat AF (Medical Device Daily, Feb. 9, 2009). The agency cleared the NaviStar ThermoCool Catheter for the treatment of drug refractory recurrent symptomatic paroxysmal AF, when used with compatible three-dimensional electroanatomic mapping systems. Biosense Webster is a division of Johnson & Johnson (New Brunswick, New Jersey).

The ThermoCool is a saline irrigated radio frequency ablation catheter that can be used to create small, strategically placed scars in heart tissue to block irregular electrical waves that cause AF. The FDA had previously approved other ablation catheters to treat arrhythmias such as atrial flutter and ventricular tachyarrhythmia, but not AF.

According to a poster presented last month at the American Heart Association (Dallas) scientific sessions in Orlando, the convergent experience combining surgical and EP expertise appears to be a "promising strategy to achieve short term success" in patients with long standing persistent atrial fibrillation (LSPAF). The researchers concluded that additional data is needed to test the long-term efficacy of this approach. According to the poster, 29 patients with LSPAF with left atrium greater than 5 centimeters have been enrolled in that study.

nContact was founded in 2005 to develop devices for the endoscopic treatment of arrhythmias, including AF. According to the company, the Numeris system with VisiTrax is based on the unique integration of suction, perfusion, and RF energy to ensure the creation of visible, non-conductive, bi-atrial epicardial lesions on a beating heart.

To date, the system is indicated for the coagulation of cardiac tissue in the U.S. nContact said it has initiated clinical studies for the treatment of AF in both open and closed chest procedures. The Numeris system with VisiTrax has CE mark approval in Europe for the specific indication for the coagulation of cardiac tissue for the treatment of AF and atrial flutter.

Since the FDA cleared the NaviStar for AF, the segment is expected to emerge as a hot area for investment and product development (MDD, July 9, 2009). Within the last year, St. Jude Medical (St. Paul, Minnesota) has acquired EP MedSystems (West Berlin, New Jersey), which has a growing franchise in EP workstations and intracardiac echo, for $92 million and MediGuide (Haifa, Israel), which has developed a tracking technology for a wide variety of interventional procedures, for more than $300 million.

Also, Medtronic (Minneapolis) bought CryoCath (Montreal) late last year (MDD, Dec. 22, 2008), which has developed a balloon catheter for AF ablation, for about $400 million and in February it announced the acquisition of AF catheter developer Ablation Frontiers (Carlsbad, California) (MDD, Feb. 9, 2009). The latter deal was for $225 million in cash plus an estimated $175 million in additional milestone payments based on achieving various regulatory approvals.

Amanda Pedersen, 229-471-4212;

amanda.pedersen@ahcmedia.com