Deepthy Varghese, MSN, ACNP, FNP, Northside Hospital is joined by James O'Hara, PhD, PA, Virginia Heart, and Shunmuga Sundaram Ponnusamy, MBBS, MD, CEPS-A, Velammal Medical College Hospital, and Research Institute to discuss a study that evaluated the impact of QRS morphology on the risk of life-threatening ventricular arrhythmias in heart failure patients treated with cardiac resynchronization therapy with a defibrillator (CRT-D). The analysis included 2,862 patients from five major ICD trials, focusing on those with a QRS duration of ≥130 ms. Patients were categorized into those receiving ICD-only or CRT-D. Key findings: Among patients with left bundle branch block (LBBB), those with CRT-D showed a significant 44% reduction in the risk of fast ventricular tachycardia (VT)/ventricular fibrillation (VF) compared to ICD-only patients. They also had a lower fast VT/VF burden and fewer appropriate shocks. In patients with non-left bundle branch block (NLBBB), CRT-D did not reduce the risk of fast VT/VF and was associated with a significant increase in the burden of fast VT/VF events compared to ICD-only patients. The study concludes that CRT-D effectively reduces life-threatening ventricular arrhythmias in LBBB patients but may increase the risk in NLBBB patients. 

https://www.hrsonline.org/education/TheLead
https://www.jacc.org/doi/10.1016/j.jacep.2023.09.018?s=03

Host Disclosure(s):
D. Varghese: Nothing to disclose. 

Contributor Disclosure(s):
J. O'Hara: Honoraria, Speaking, and Consulting: Medtronic Inc., Boston Scientific 
S. Ponnusamy: Honoraria, Speaking, and Consulting: Medtronic Inc.