Clinical Trial at Mission Health Studies New Way to Treat Persistent Atrial Fibrillation


August 18, 2014

August 18, 2014 — A clinical trial being conducted at Mission Health using Medtronic's Phased Radiofrequency (RF) ablation system, may one day help people with persistent atrial fibrillation that does not respond to medication.

The trial, known as VICTORY-AF (which stands for Evaluation of Multielectrode Phased RF Technology in Persistent AF), is what is known as a prospective, non-randomized study. In essence, patients who present to their doctor with a certain set of criteria outlined by a clinical trial protocol are eligible to receive treatment with this device. In this study, patients with persistent or long-standing persistent atrial fibrillation (AF) undergo an ablation procedure with a the phased RF system.

In the United States, ablation catheters currently are available only for treating the mildest form of AF in which the heart's upper chambers beat rapidly and irregularly during episodes lasting from a few minutes to a few days. AF can progress into a persistent or long-standing persistent state, where patients do not respond to the drugs typically used to control this condition. Patients with persistent and long-standing persistent AF can have debilitating symptoms and are increased risk for stroke and hospitalizations, and can experience a reduced quality of life.

Persistent AF is defined as sustained AF lasting more than seven days but less than one year, or lasting fewer than seven days but requiring cardioversion through medication or electrical current. Long-standing persistent AF is defined as continuous AF lasting more than one year but fewer than four years.

Joseph Souza, M.D., director of the cardiac electrophysiology laboratory at Mission Hospital, leads the clinical trial in western North Carolina. Mission Health is one of only two centers in North Carolina participating in this trial, and the only one to date that has used the device. In total, 40 centers throughout the United States, Canada and Europe participate in the VICTORY-AF clinical trial. About 300 patients will be treated in the trial — 200 of those will come from the U.S. Mission Health has the second highest number of enrollments in the VICTORY-AF trial in the country.

What is special about this catheter, said Souza, is that previous trials on this device have refined the number of individual catheters needed, and found that those that had gold tips work better than previous versions that were tipped with platinum.

“With these trials,” said Souza, “we can get our hands on something that is an improvement over traditional catheters used in this procedure. Trials can get us closer to solving common problems for which we have limited solutions.”

“Trials can advance the practice of medicine by not only introducing new devices into wide use, but can provide better outcomes for patients — not only in relation to the devices themselves, but by improving safety, cutting down on repeat procedures and sometimes the amount of time the patient needs to be under anesthesia. They often offer cost savings in other ways,” Souza adds.

To date, Souza has used the device in three patients. Several other good candidates have also been identified.

The Medtronic Phased RF System is currently approved for use in areas of Europe, Asia, Africa, Australia and Canada. More than 20,000 patients in 26 countries have been treated with this system since January 2009.

Souza has participated in or directed clinical trials at Mission since 1998.

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