Feature | March 24, 2015

Ablation During Mitral Valve Surgery Reduces Atrial Fibrillation

First randomized controlled trial shows benefits of ablation during mitral valve surgery

March 24, 2015 — Patients with atrial fibrillation (AF) who received ablation while they were already undergoing surgery to correct a leaky mitral valve had fewer episodes of AF a year later compared to patients who had the valve surgery alone. This was according to a study presented at the American College of Cardiology (ACC) 2015 meeting.


During the “Surgical Ablation Versus No Surgical Ablation for Patients With Atrial Fibrillation Undergoing Mitral Valve Surgery” study, patients who received ablation along with mitral valve surgery had no more deaths, adverse cardiac events or hospitalizations than patients who only received the valve surgery alone, but they were more likely to require a pacemaker.
The study, which included 260 patients within the Cardiothoracic Surgical Trials Network, a clinical research network involving 20 U.S. and Canadian hospitals, is the first appropriately powered randomized clinical trial to assess the use of ablation in patients already undergoing mitral valve surgery. Half of the patients were randomly assigned to receive mitral valve surgery alone, while the other half also received surgical ablation. All of the study participants had persistent or long-standing persistent atrial fibrillation and were undergoing surgery to repair or replace the heart’s mitral valve, which controls movement of blood from the left atrium to the left ventricle.
Of the patients who received ablation and mitral valve surgery, 63 percent were free from AF at six and 12 months after surgery, while 29 percent of patients who received mitral valve surgery alone were free from AF at those time points. Mitral valve surgery is typically performed to correct a leaking or narrowed valve. Although the procedure is unrelated to AF, many patients in need of valve repair also have atrial fibrillation, so surgeons have begun combining the two procedures in order to address both cardiac issues at the same time.
“Although surgeons are widely performing ablation at the time of mitral valve surgery, there is a great deal of variation with regard to when it is done, how it is done and which patients receive it,” said Marc Gillinov, M.D., the Judith Dion Pyle Chair in Heart Valve Research at Cleveland Clinic and the study’s lead author. “We sought to conduct a well-designed randomized controlled trial to answer fundamental questions about whether this procedure is successful and how it is best done.”
In the absence of strong clinical guidance regarding the use of ablation with mitral valve surgery, the decision is left largely up to physician preference, Gillinov said. About two-thirds of surgeons currently perform ablation during mitral valve surgery for patients with persistent atrial fibrillation, while one-third do not.
The National Institutes of Health and Canadian Institutes for Health Research supported the design and conduct of the trial.
While the patients receiving ablation were significantly more likely to be free of AF six and 12 months after surgery, the study showed no significant differences in rates of death, adverse cardiac events or hospitalization. Patients receiving the mitral valve surgery alone reported a slightly lower quality of life because more of these patients said they still experienced daily AF a year after the surgery.
“I think what this shows is that, in the mitral valve surgery patient who has persistent atrial fibrillation, you will achieve better rhythm control by performing ablation, without any increase in mortality or other adverse cardiac events,” Gillinov said.
However, the analysis also revealed one potential downside to including ablation with mitral valve surgery. Patients receiving the ablation along with the mitral valve surgery were 2.5 times more likely to require the implantation of a pacemaker in the year following their surgery. The reason for this difference is unknown and warrants further study, Gillinov said.
Because there are several tools and techniques physicians can choose when performing surgical ablation, researchers decided to randomly assign patients receiving the ablation to either pulmonary vein isolation, in which the surgeon uses heat or cryothermy energy to destroy a small area of tissue in the heart, or a biatrial Maze lesion, in which the surgeon makes a complex series of lesions to correct abnormal electrical impulses. The analysis showed no significant differences in the outcomes for patients undergoing the two procedure types, though a larger study would help to elucidate any differences, Gillinov said.
Because patients have only been tracked for one year, the results do not yet provide a clear picture of the full spectrum of potential differences in cardiovascular outcomes. The researchers will continue to track patients to assess any long-term differences in survival, hospitalization, stroke and other outcomes.
This study was simultaneously published online in the New England Journal of Medicine at the time of presentation.
For more information: acc.org

Related Content

FDA Issues Final Guidance on Live Case Presentations During IDE Clinical Trials
News | Cardiovascular Clinical Studies | July 10, 2019
The U.S. Food and Drug Administration (FDA) issued the final guidance “Live Case Presentations During Investigational...
Veradigm Partners With American College of Cardiology on Next-generation Research Registries
News | Cardiovascular Clinical Studies | July 03, 2019
The American College of Cardiology (ACC) has partnered with Veradigm, an Allscripts business unit, to power the next...
New FDA Proposed Rule Alters Informed Consent for Clinical Studies
News | Cardiovascular Clinical Studies | November 19, 2018
The U.S. Food and Drug Administration (FDA) is proposing to add an exception to informed consent requirements for...
A key slide from Elnabawi's presentation, showing cardiac CT plaque evaluations, showing the impact of psoriasis medication on coronary plaques at baseline and one year of treatment. It shows a reversal of vulnerable plaque development. #SCAI, #SCAI2018

A key slide from Elnabawi's presentation, showing cardiac CT plaque evaluations, showing the impact of psoriasis medication on coronary plaques at baseline and one year of treatment. It shows a reversal of vulnerable plaque development.  

Feature | Cardiovascular Clinical Studies | May 14, 2018
May 14, 2018 – New clinical evidance shows common therapy options for psoriasis (PSO), a chronic inflammatory skin di
Intravenous Drug Use is Causing Rise in Heart Valve Infections, Healthcare Costs. #SCAI, #SCAI2018
News | Cardiovascular Clinical Studies | May 14, 2018
May 14, 2018 — The opioid drug epidemic is impacting cardiology, with a new study finding the number of patients hosp
Patient Enrollment Completed in U.S. IDE Study of THERMOCOOL SMARTTOUCH SF Catheter
News | Cardiovascular Clinical Studies | March 15, 2018
March 15, 2018 –  Johnson & Johnson Medical Devices Companies announced today that Biosense Webster, Inc., who wo
Lexington Begins HeartSentry Clinical Trial
News | Cardiovascular Clinical Studies | February 20, 2018
February 20, 2018 – Lexington Biosciences, Inc., a development-stage medical device company, announced the commenceme
Endologix Completes Patient Enrollment in the ELEVATE IDE Clinical Study
News | Cardiovascular Clinical Studies | February 06, 2018
February 6, 2018 – Endologix, a developer and marketer of treatments for aortic disorders, announced the completion o
12-Month Results from Veryan Medical's MIMICS-2 IDE Study Presented at LINC
News | Cardiovascular Clinical Studies | February 01, 2018
February 1, 2018 – Thomas Zeller (Bad Krozingen, Germany) presented the 12-month results from Veryan Medical’s MIMICS
LimFlow Completes U.S. Feasibility Study Enrollment, Receives FDA Device Status
News | Cardiovascular Clinical Studies | February 01, 2018
February 1, 2018 –  LimFlow SA, developer of minimally-inv
Overlay Init