New Evidence for ICD Decision-Making in Cardiomyopathy Patients with LVEF 36-50% Presented at ESC Congress
- BIOTRONIK-Supported CMR-GUIDE Trial Evaluates Scar-Based Risk Stratification for ICD Therapy
- Primary Endpoint Neutral; Secondary Endpoint Shows Reduced Sudden Cardiac Death with ICD Therapy
Results from the CMR-GUIDE study were presented by Principal Investigator Prof Dr. Joseph Selvanayagam, Chair of Cardiovascular Medicine at Flinders University, Flinders Medical Centre, Adelaide, Australia, during a Hotline Session at the European Society of Cardiology (ESC) Congress 2026 in Munich, Germany. The findings were also published online in JAMA.
Current guidelines generally do not recommend primary-prevention ICD implantation for patients with left ventricular ejection fraction (LVEF) greater than 35%, despite many sudden cardiac deaths occurring in this population. CMR-GUIDE was designed to address this unmet clinical need. It examined whether cardiac magnetic resonance (CMR) imaging could help identify patients at elevated risk who may benefit from ICD therapy.
CMR-GUIDE evaluated a CMR-guided approach to ICD therapy in patients with LVEF 36-50% and evidence of myocardial scar. The study enrolled 353 patients with ischemic or non-ischemic cardiomyopathy, LVEF 36-50%, and CMR-confirmed myocardial scar across 18 sites in Australia, Germany, and the United Kingdom. Participants were randomized to receive either an ICD or long-term monitoring with an implantable loop recorder and were followed for a median of 6.3 years.
The study found that ICD implantation did not significantly reduce the primary composite endpoint of sudden cardiac death (SCD) or hemodynamically significant ventricular arrhythmia (HSVA) compared with implantable loop recorder monitoring. However, ICD therapy was associated with a significant reduction in SCD and demonstrated benefit in the pre-specified subgroup of patients younger than 70 years.
“These findings add important evidence for a patient population where ICD treatment decisions are often uncertain. While the primary endpoint was neutral, the reduction in sudden cardiac death and the benefit observed in younger patients provide important insights for individual treatment decisions,” said Dr. Selvanayagam.
CMR-GUIDE was funded by BIOTRONIK as part of its commitment to advancing independent clinical research in heart failure and arrhythmia management. Its CMR-based risk stratification approach offers physicians additional information to support individualized patient management.
“We are grateful to Dr. Selvanayagam and the investigator team for their work on this important trial. Independent research that helps clarify unanswered clinical questions is central to advancing patient care. These results provide another data point for physicians and patients when an ICD implant is considered,” said Dr. David Hayes, Chief Medical Officer at BIOTRONIK.
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For over 60 years, BIOTRONIK has stood at the forefront of medical technology, pioneering breakthrough innovations that are transforming the lives of millions affected by heart disease and chronic pain. Rooted in a deep purpose to seamlessly harmonize technology with the human body, we engineer trusted, life-changing therapies through our advanced active implants in Cardiac Rhythm Management, Monitoring, and Neuromodulation, while providing cutting-edge solutions in Electrophysiology. From creating Germany’s first pacemaker in 1963 to breaking new ground in digital technologies and Conduction System Pacing today, BIOTRONIK is continuously raising the bar for quality, performance, and innovation. Headquartered in Berlin, our global reach spans over 100 countries across the Americas, EMEA, and Asia—bringing bold, future-ready solutions that are shaping the next generation of medical technology.
