Country's first 'simplified maze' using new ultrasound technology is done at Northwestern Memorial


Dr. Patrick McCarthy performs surgical first that opens the door to surgical cure for a wider segment of the 2.4 million Americans with atrial fibrillation

CHICAGO The country's first ever Maze procedure done using high intensity focused ultrasound technology the only energy source that allows surgeons to surgically cure atrial fibrillation (AF) while a patient's heart is beating rather than having to use a heart-lung bypass machine was performed last Friday at the Northwestern Cardiovascular Institute at Northwestern Memorial Hospital in Chicago.

Atrial fibrillation is a widespread cardiac rhythm disorder in which the upper chambers of the heart do not beat effectively because of abnormal electrical activity. AF results in reduced cardiac output, exacerbates heart failure and can lead to stroke or other neurological problems. AF affects more than six million people worldwide.

"Ultrasound technology dramatically simplifies the Maze procedure, eliminates the need to stop the heart from beating and soon will allow us to perform the Maze procedure minimally invasively and routinely as a stand-alone surgery," says Patrick McCarthy, M.D., co-director of the Northwestern Cardiovascular Institute and chief of cardiothoracic surgery at Northwestern Memorial Hospital, who performed the country's surgical first and is one of the few surgeons trained to use the High Intensity Focused Ultrasound (HIFU) surgical ablation technology manufactured by St. Jude Medical, Inc.

"Northwestern Memorial Hospital is an outstanding partner to debut our HIFU technology to the United States," said Jane J. Song, President of St. Jude Medical's Atrial Fibrillation business. "Dr. McCarthy's renowned international reputation and vast experience in the surgical treatment of atrial fibrillation, combined with Northwestern Memorial's commitment to building a premier heart program, make them the ideal team to introduce this new approach to surgical cardiac ablation." The Maze procedure is the most effective cure for AF, eliminating irregular heartbeats a primary reason for stroke, heart attacks and heart failure in 97 percent of patients. While considered the gold standard in surgical treatment of AF, the Maze procedure is only performed by a handful of surgeons across the country because it is so technically challenging. In addition, because it requires patients to go on a heart-lung machine for up to an hour, it has typically been reserved for patients requiring other cardiac surgical procedures, such as coronary artery bypass graft or valve repair.

"While the Maze procedure is routine and incredibly safe when done by those surgeons who are experienced with the technique, many physicians still think of it as a failure if a patient with AF does not respond to medical therapy and has to be referred for surgery," says Dr. McCarthy. "The perceived magnitude of this surgery and the possibility of some complications associated with the heart-lung machine are responsible for this trend. The ultrasound technology enables us to perform a 'simplified Maze' that is highly reproducible. This innovation is likely to lead to more surgeons who can do the procedure and more patient referrals as physicians begin to consider the Maze a much simpler and safer surgery that doesn't require heart-lung bypass. I think we'll also begin seeing earlier referrals rather than this being the treatment of last resort."

In the Maze procedure, maze-like patterns are strategically made in the left upper chamber of the heart to interrupt the electrical signals causing the irregular heartbeat. Scar tissue, which does not conduct electrical activity, forms and prevents erratic electrical signals from recurring. The HIFU technology allows surgeons to recreate these patterns by placing a device that delivers high-intensity focused ultrasound to the outside of the heart in a precise pattern. When combined with another cardiac procedure, the 'simplified Maze' using the HIFU system adds less than five minutes to the overall procedure time.

"I anticipate that soon I'll begin doing the 'simplified Maze' procedure with the HIFU technology minimally invasively with only about an 8 cm incision and sending patients home after a day or two instead of after five days as is currently typical in patients who've had a Maze procedure," says Dr. McCarthy.

The NCVI includes a core infrastructure of six centers: The Center for Heart Valve Disease, The Center for Heart Failure, The Center for Atrial Fibrillation, The Center for Coronary Disease, the Center for Vascular Disease and the Center for Women's Health. "Launching the HIFU technology in the U.S. is the beginning of what we expect to be many national firsts at Northwestern's recently established Center for Atrial Fibrillation. We are intensely focused on researching the genetics that predispose patients to develop AF and are now ready to launch piloting minimally invasive surgical technology for AF."

Source: Eurekalert & others

Last reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
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