Piotr Gardziejczyk, Yuichiro Sagawa, Arian Afzalian, Alireza Oraii, Michael Stuckey, Rajat Deo, Sanjay Dixit, Andrew E Epstein, Gustavo S Guandalini, Balaram Krishna J Hanumanthu, Matthew C Hyman, Ramanan Kumareswaran, David Lin, Timothy M Markman, Maiwand Mirwais, Saman Nazarian, Michael P Riley, Robert D Schaller, Vincent See, Poojita Shivamurthy, Gregory E Supple, Cory M Tschabrunn, David J Callans, David S Frankel, Fermin C Garcia, Francis E Marchlinski, Andres Enriquez
PVS represents a useful tool for risk stratification of arrhythmic events in patients with NICM, myocardial scar and preserved or mildly reduced LVEF, identifying those who may benefit from primary prevention ICD implant.
BACKGROUND: A substantial proportion of sudden cardiac deaths occur in patients with nonischemic cardiomyopathy (NICM) and left ventricular ejection fraction (LVEF) ≥40% who do not meet current criteria for implantable cardioverter-defibrillator (ICD) implantation.
OBJECTIVES: This study sought to evaluate programmed ventricular stimulation (PVS) for arrhythmic risk stratification in patients with NICM, cardiac magnetic resonance-confirmed myocardial scar, and LVEF ≥40%.
METHODS: Consecutive patients with NICM, LVEF ≥40%, late gadolinium enhancement on cardiac magnetic resonance, and frequent premature ventricular complexes (PVCs; >5%) or nonsustained ventricular tachycardia who underwent PVS at a tertiary center (2014-2025) were included. The primary outcome was a major arrhythmic event (MAE): sustained ventricular tachycardia/fibrillation, appropriate ICD therapy, or sudden cardiac death.
RESULTS: Among 182 patients (median aged 62 years; 33% women), PVS was positive in 45 (25%). Over a median 3.5-year follow-up, MAE occurred in 13 of 45 PVS-positive (29%) vs 2 of 137 PVS-negative patients (1.5%; P < 0.001), yielding a negative predictive value of 98.5%. Additional MAE predictors included multifocal PVCs/nonsustained ventricular tachycardia (HR: 6.6; 95% CI: 1.8-24.4), family history of sudden cardiac death (HR: 16.7; 95% CI: 4.5-62.3), QRS ≥100 milliseconds (HR: 5.2; 95% CI: 1.4-19.2), and LVEF ≤50% (HR: 4.4; 95% CI: 1.4-13.4; all P < 0.05). A noninvasive risk score incorporating these 4 variables yielded an optimism-corrected C-statistic of 0.892 (95% CI: 0.805-0.957).
CONCLUSIONS: PVS represents a useful tool for risk stratification of arrhythmic events in patients with NICM, myocardial scar and preserved or mildly reduced LVEF, identifying those who may benefit from primary prevention ICD implant.