Pilot Study Shows Cryoablation Is Safe and Effective for Closing a Small Hole in the Heart in Patients with Atrial Fibrillation

New research shows that cryoablation is a safe and effective approach to close congenital patent foramen ovale (PFO, a small hole in the heart) in patients with atrial fibrillation (AF) undergoing pulmonary vein isolation (PVI) in a single procedure. A new study in Heart Rhythm, the official journal of the Heart Rhythm Society, the Cardiac Electrophysiology Society, and the Pediatric & Congenital Electrophysiology Society, published by Elsevier, details this alternative method to the conventional treatment of implementing a percutaneous metal device for PFO closure, which is associated with adverse events such as infection and arrhythmia.

In adults, the prevalence of PFO ranges between 20% and 34%. PFO is associated with a variety of disorders, including cryptogenic stroke, transient ischemic attack (TIA), migraine, and decompression sickness. Percutaneous device occlusion is currently the standard therapeutic option for PFO-related ischemic stroke. However, there are risks associated with implantation of this permanent device, including infection, pericardial effusion, device displacement, thrombus development, and arrhythmia. Furthermore, a metal occluder would obstruct future access to the left atrium in interventional treatments such as catheter ablation for AF, mitral valve clamping, and left atrial appendage occlusion.

This study presents the first use of cryoablation, a minimally invasive procedure that uses extreme cold, to induce PFO closure.

Co-lead investigator of the study Jiang Deng, MMed, Department of Cardiovascular Medicine, Yongchuan Hospital of Chongqing Medical University, Chongqing, China, notes, "The pursuit of an ideal PFO closure method without a residual device is a compelling endeavor. Our aim was to investigate the efficacy and safety of PFO closure using cryoablation without implantation in patients with atrial fibrillation who underwent PVI. We postulated that cryoablation can also fuse PFO by injuring the primary and secondary septum."

Co-lead investigator EnRun Wang, MMed, Department of Cardiovascular Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China, explains, "Although AF and PFO are both risk factors for stroke/TIA, it is difficult to determine whether PFO is involved in the development of stroke when the two disorders co-occur. The advantages of PVI in conjunction with PFO closure are unknown. Our aim was to investigate whether atrial septal (AS) cryoablation could lead to secondary PFO closure in individuals with AF who undergo PVI."

The study enrolled a group of 22 patients with symptomatic drug-refractory paroxysmal or short-time persistent AF and PFO who were admitted for PVI via cryoablation from the First Hospital of Chongqing Medical University. Eligible patients were divided into the standard PVI + AS cryoablation group and the standard PVI group. The research was designed to determine the PFO closure rate, procedure-related complications, the recurrence of AF, and stroke/TIA events. Patients who underwent AS cryoablation had a significantly higher rate of successful PFO closure than individuals who only had balloon inflation. There was no difference in procedure-related adverse events, AF recurrence, and ischemic stroke/TIA events in both groups.

Nir Flint, MD, Division of Cardiology, Tel Aviv Sourasky Medical Center and Tel Aviv University School of Medicine, Tel Aviv, Israel, coauthor of an accompanying editorial commentary, notes, "The notion of a ‘no footprint,’ device-free, percutaneous PFO closure presents potential benefits. This procedure theoretically mimics the physiologic healing and closure of the PFO by inducing inflammation and scarring, creating an anatomic closure of the interatrial septum. This approach minimizes the adverse events associated with artificial materials and allows future interventions if needed."

Eyal Ben-Assa, MD, Division of Cardiology, Assuta Ashdod University Hospital and Ben Gurion University, Ashdod, Israel, coauthor of the commentary, concludes, "This study presents an innovative approach to PFO closure by cryoballoon ablation, showcasing its potential as a device-free alternative. The authors wisely performed this procedure on patients undergoing ablation of AF with a closing-the-door-on-your-way-out approach. Whereas preliminary results are promising, further research is needed to enhance efficacy and to confirm safety. This technique could pave the way for new strategies in PFO management, particularly for patients undergoing ablation procedures."

Notes for editors

The article is “Feasibility and safety of cryoballoon ablation for atrial fibrillation and closing patent foramen ovale without implantation: a pilot study," by Jiang Deng, MMed, EnRun Wang, MMed, Gang Liu, MD, ChunChang Qin, MD, Qian Dong, MD, Wei Yang, MMed, YanFei Wang, MMed, Rana Abdul Qadir, MMed, and Fengpeng Jia, MD (https://doi.org/10.1016/j.hrthm.2024.06.006). It is openly available for 30 days at https://www.heartrhythmjournal.com/article/S1547-5271(24)02682-1/fulltext.

Journalists wishing to interview the authors should contact Fengpeng Jia, MD, at [email protected].

This work was supported by the Graduate Research and Innovation Project of Chongqing (project number CYS23329).

The editorial commentary is "Patent foramen ovale closure with cryoballoon ablation: ‘Please close the door on your way out.’" by Nir Flint, MD, and Eyal Ben-Assa, MD (https://doi.org/10.1016/j.hrthm.2024.07.120). It is openly available for 30 days at https://www.heartrhythmjournal.com/article/S1547-5271(24)03099-6/fulltext.

The articles appear in Heart Rhythm, volume 21, Issue 12 (December 2024), published by Elsevier.

Full text of the articles is also available to credentialed journalists upon request; contact Jane Grochowski at +1 406 542 8397 or [email protected].

About Heart Rhythm

Heart Rhythm, the official Journal of the Heart Rhythm Society, the Cardiac Electrophysiology Society, and the Pediatric & Congenital Electrophysiology Society, is a unique journal for fundamental discovery and clinical applicability. It integrates the entire cardiac electrophysiology (EP) community from basic and clinical academic researchers, private practitioners, engineers, allied professionals, industry, and trainees, all of whom are vital and interdependent members of our EP community. www.heartrhythmjournal.com

About the Heart Rhythm Society

The Heart Rhythm Society is the international leader in science, education, and advocacy for cardiac arrhythmia professionals and patients, and the primary information resource on heart rhythm disorders. Its mission is to improve the care of patients by promoting research, education, and optimal healthcare policies and standards. The Heart Rhythm Society is the preeminent professional group representing more than 8,000 specialists in cardiac pacing and electrophysiology from more than 94 countries. www.HRSonline.org

About Elsevier

Elsevier is a global leader in advanced information and decision support. For over a century, we have been helping advance science and healthcare to advance human progress. We support academic and corporate research communities, doctors, nurses, future healthcare professionals and educators across 170 countries in their vital work. We do this by delivering mission-critical insights and innovative solutions that combine trusted, evidence-based scientific and medical content with cutting-edge AI technologies to help impact makers achieve better outcomes. We champion inclusion and sustainability by embedding these values into our products and culture, working with the communities that we serve. The Elsevier Foundation supports research and health partnerships around the world.

Elsevier is part of RELX, a global provider of information-based analytics and decision tools for professional and business customers. For more information, visit www.elsevier.com and follow us on social media @ElsevierConnect.