Contemporary Use of Implantable Cardioverter-Defibrillators in the Era of 4-Pillar Heart Failure Therapy---an International Survey

Background: Optimized 4-pillar guideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF) has significantly altered clinical practice, with a coinciding decrease in sudden cardiac death. The continued role for implantable cardioverter-defibrillators (ICDs) in primary prevention of sudden death has recently been debated in the context of residual arrhythmic risk. This survey explored contemporary attitudes toward primary prevention ICD use in ischemic and nonischemic cardiomyopathy. Methods: An international, REDCap-based survey targeting clinicians involved in HFrEF management assessed the impact of GDMT on ICD decision-making, clinical thresholds used for implantation, and willingness to participate in randomized controlled trials. Results: = 0.003). Clinical thresholds based on left ventricular ejection fraction and New York Heart Association class were common, whereas age, renal function, and late gadolinium enhancement cut-offs were used less frequently. Willingness to randomize patients into ICD vs no-ICD trials was moderate for ischemic cardiomyopathy (38.8% for all patients, 31.8% for select patients). In nonischemic cardiomyopathy, willingness was higher, with 51.2% willing to randomize all patients and only 9.3% declining. Free-text responses emphasized individualized decision-making and the growing role of imaging and genetics. Conclusions: In the era of optimized GDMT, practice patterns regarding primary prevention ICD implantation are increasingly heterogeneous. These findings underscore the need for nuanced shared decision-making and well-designed randomized controlled studies to guide future practice.