Abbott has announced that it has received US Food and Drug Administration (FDA) approval and a CE mark for the UltiSynq defibrillation lead, which is designed for implantation in the left bundle branch area (LBBA) of the heart to deliver both conduction system pacing (CSP) and defibrillation therapy. These approvals covering the USA and EU provide an additional lead option for patients who are candidates for both CSP and defibrillation protection, as noted in an Abbott press release.
The release also states that the UltiSynq defibrillation lead is designed for long-term attachment to compatible implantable cardioverter-defibrillator (ICD) or cardiac resynchronisation therapy defibrillator (CRT-D) systems in patients who are at risk of sudden cardiac death due to life-threatening tachyarrhythmias.
The US FDA and CE-mark approvals of the UltiSynq defibrillation lead were supported by results from the ASCEND CSP investigational device exemption (IDE) trial—a prospective, multicentre, global study evaluating the safety and effectiveness of UltiSynq in patients indicated for therapy involving an ICD or CRT-D device.
Presented as late-breaking data at the 2026 Heart Rhythm Society (HRS) annual meeting (23–26 April, Chicago, USA), three-month results from the study demonstrated that the UltiSynq defibrillation lead exceeded all prespecified primary safety and effectiveness endpoints.
Key study findings were as follows:
- Among 205 implant attempts, lead implantation was successful in 98.5% of patients
- Leads required a mean of less than one repositioning attempt per patient to identify the pacing target
- Among successfully implanted patients, 86% achieved left bundle branch pacing (LBBP) or likely LBBP, meaning the lead stimulated or likely stimulated the heart’s natural conduction pathway—while the remaining 14% had left ventricular septal pacing
- The three-month major complication-free rate was 97.5%, exceeding the prespecified safety performance goal
- In the 120 patients who completed defibrillation testing, successful defibrillation was observed at a rate of 100%, and no lead repositioning was required to achieve defibrillation
Abbott states that UltiSynq is built on a proven, reliable ICD lead platform with distinct, true bipolar sensing, which uses two closely spaced electrodes within the lead to accurately detect the heart’s signals from the ventricles. It incorporates a short shock coil designed to support positioning precision. UltiSynq’s ease of implantation is designed to deliver CSP benefits, working with the heart’s natural electrical wiring system for a coordinated heartbeat, while its true bipolar sensing may help reduce susceptibility to P-wave oversensing, which occurs when a device mistakes the upper heart’s signal for a lower chamber beat and could trigger unnecessary therapy.
“UltiSynq demonstrates what is achievable when a lead is designed to support CSP,” said Pugazhendhi Vijayaraman (Geisinger Heart Institute, Danville, USA). “The observed implant success, LBBAP [left bundle branch area pacing] capture results, and defibrillation testing outcomes, give physicians compelling data on this lead option for patients who require defibrillation protection and are candidates for CSP.”
“UltiSynq represents an important advance as Abbott continues to build a comprehensive cardiac rhythm management portfolio,” added Randel Woodgrift, senior vice president of Abbott’s cardiac rhythm management business. “Physicians now have a compelling option for CSP in patients who also need ICD or CRT-D therapy. UltiSynq extends physiologic pacing to patients who require both rhythm management and defibrillation protection.”
