Implications of ventricular arrhythmia after cardiac resynchronization therapy.

Background: Conflicting data are available on whether ventricular arrhythmia (VA) or shock therapy increases mortality. Although cardiac resynchronization therapy (CRT) reduces the risk of VA, little is known about the prognostic value of VA among patients with CRT devices.
Objectives: The purpose of this study was to evaluate the implications of VA as a prognostic marker for CRT.
Methods: We investigated 330 CRT patients within 1 year after CRT device implantation. The primary endpoint was the composite endpoint of all-cause death or hospitalization for heart failure.
Results: Forty-three patients had VA events. These patients had a significantly higher risk of the primary endpoint, even among CRT responders (P = .009). Fast VA compared to slow VA was associated with an increased risk of the primary endpoint (hazard ratio [HR] 2.14; 95% confidence interval [CI] 1.06-4.34; P = .035). Shock therapy was not associated with a primary endpoint (shock therapy vs antitachycardia pacing: HR 1.49; 95% CI 0.73-3.03; P = .269). The patients with VA had a lower prevalence of response to CRT (23 [53%] vs 202 [70%]; P = .031) and longer left ventricular paced conduction time (174 ± 23 ms vs 143 ± 36 ms; P = .003) than the patients without VA.
Conclusion: VA occurrence within 1 year was related to paced electrical delay and poor response to CRT. VA could be associated with poor prognosis among CRT patients.
Competing Interests: Disclosures Dr Ueda received honoraria from Medtronic Japan Co., Ltd. for providing lectures. Dr Ishibashi received honoraria for teaching lectures from BIOTRONIK Japan and Medtronic Japan Co., Ltd. Dr Noda received honoraria for lectures from Medtronic Japan Co., Ltd. and BIOTRONIK Japan, Inc.; and belongs to a department endowed by BIOTRONIK Japan. Dr Dr Nagase is affiliated with a department endowed by Japan Medtronic Inc. Dr Kusano received honoraria from BIOTRONIK Japan and Medtronic Japan; and research grants from Medtronic Japan. However, none of these disclosures were directly associated with this study. All other authors have no conflicts to disclose.
(Copyright © 2023 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)