Heart Rhythm 2026: Ventricular Tachycardia Benefits From Ultra-Low Temperature Ablation

New FULCRUM-VT trial results show that ultra-low temperature ablation (ULTA) may be a promising new treatment option for patients with ventricular tachycardia (VT) and structural heart disease. Researchers presented these findings during Heart Rhythm 2026.

VT occurs when the heart’s lower chambers beat dangerously fast, preventing the heart from pumping blood effectively. It is a leading cause of sudden cardiac death, which accounts for an estimated 15% to 20% of deaths worldwide.ⁱ In the United States alone, more than 356,000 out-of-hospital cardiac arrests occur annually, many because of ventricular arrhythmias such as VT.ⁱⁱ VT most commonly affects patients with structural heart disease, in which scar tissue disrupts normal cardiac electrical conduction and leads to potentially life-threatening rhythm disturbances.

Although ablation is commonly used to treat VT, conventional approaches may be less effective in reaching deeper or heavily scarred tissue. ULTA, however, offers a promising alternative. By using extreme cold—near-critical nitrogen with a boiling point of -196°C—this approach can more effectively target these challenging areas and may provide a new treatment option for patients with difficult-to-manage arrhythmias.

The pivotal multicenter FULCRUM-VT trial evaluated the safety and effectiveness of ULTA in 209 patients with structural heart disease undergoing VT ablation at 19 U.S. and Canadian sites. The study enrolled patients with both ischemic and non-ischemic cardiomyopathy, many of whom had implantable cardioverter-defibrillators (ICDs) and were already receiving antiarrhythmic medications, including amiodarone. This high-risk population had advanced disease, with a 35% mean left ventricular ejection fraction, and continued to experience arrhythmias despite prior therapy. During each procedure, doctors used the ULTA system to precisely target and ablate the areas of heart tissue responsible for initiating and supporting VT.

In the study, ULTA demonstrated high effectiveness and a favorable safety profile for treating scar-related VT in cardiomyopathy patients. Post-ablation testing confirmed the treating physicians could no longer induce 98% of targeted VTs, thus eliminating these abnormal heart rhythms. Investigators observed major adverse events in only 2.5% of patients, indicating the procedure was generally well tolerated.

“Ventricular tachycardia in cardiomyopathy patients can be challenging to treat, particularly when scar tissue interferes with the heart’s normal electrical pathways,” said Atul Verma, M.D., senior scientist at the Research Institute of the McGill University Health Centre at Montreal General Hospital. “This study points to using ultra-low-temperature ablation as a new approach to safely and effectively target difficult arrhythmia circuits, potentially improving treatment options for patients.”

Researchers will continue assessing the ways in which ULTA procedures affect VT recurrence over time and will share upcoming data on six-month and longer-term patient outcomes.

The Heart Rhythm Society is the international leader in science, education, and advocacy for cardiac arrhythmia professionals and patients and is the primary information resource on heart rhythm disorders. Its mission is to improve patient care by promoting research, education, and optimal healthcare policies and standards. Incorporated in 1979 and based in Washington, D.C., its membership consists of more than 9,000 heart rhythm professionals from 94 countries.

The Heart Rhythm Society’s annual Heart Rhythm meeting convenes 10,000 of the world’s clinicians, scientists, researchers, and innovators in cardiac pacing and electrophysiology. More than 2,000 international experts in the field serve as faculty for the 200-plus educational sessions, forums, symposia, and ceremonies, while over 110 exhibitors showcase their products and services.

References
i Priori SG, Blomström-Lundqvist C, Mazzanti A, et al. 2015 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. European Heart Journal. 2015;36(41):2793–2867.
ii American Heart Association. Cardiac arrest statistics. American Heart Association; 2023. Available at: https://cpr.heart.org/en/resources/cpr-facts-and-stats