Longer right to left ventricular activation delay at cardiac resynchronization therapy implantation is associated with improved clinical outcome in left bundle branch block patients.

Abstract

AIMS:

Data on longer right to left ventricular activation delay (RV-LV AD) predicting clinical outcome after cardiac resynchronization therapy (CRT) by left bundle branch block (LBBB) are limited. We aimed to evaluate the impact of RV-LV AD on N-terminal pro-B-type natriuretic peptide (NT-proBNP), ejection fraction (EF), and clinical outcome in patients implanted with CRT, stratified by LBBB at baseline.

METHODS AND RESULTS:

Heart failure (HF) patients undergoing CRT implantation with EF ≤ 35% and QRS ≥ 120 ms were evaluated based on their RV-LV AD at implantation. Baseline and 6-month clinical parameters, EF, and NT-proBNP values were assessed. The primary endpoint was HF or death, the secondary endpoint was all-cause mortality. A total of 125 patients with CRT were studied, 62% had LBBB. During the median follow-up of 2.2 years, 44 (35%) patients had HF/death, 36 (29%) patients died. Patients with RV-LV AD ≥ 86 ms (lower quartile) had significantly lower risk of HF/death [hazard ratio (HR): 0.44; 95% confidence interval (95% CI): 0.23-0.82; P = 0.001] and all-cause mortality (HR: 0.48; 95% CI: 0.23-1.00; P = 0.05), compared with those with RV-LV AD < 86 ms. Patients with RV-LV AD ≥ 86 ms and LBBB showed the greatest improvement in EF (28-36%; P<0.001), NT-proBNP (2771-1216 ng/mL; P < 0.001), and they had better HF-free survival (HR: 0.23, 95% CI: 0.11-0.49, P < 0.001) and overall survival (HR: 0.35, 95% CI: 0.16-0.75; P = 0.007). There was no difference in outcome by RV-LV AD in non-LBBB patients.

CONCLUSION:

Left bundle branch block patients with longer RV-LV activation delay at CRT implantation had greater improvement in NT-proBNP, EF, and significantly better clinical outcome.

• Authors: Annamaria Kosztin, Valentina Kutyifa, Vivien Klaudia Nagy, Laszlo Geller, Endre Zima, Levente Molnar, Szabolcs Szilagyi, Emin Evren Ozcan, Gabor Szeplaki, Bela Merkely
• Journal: Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology (Europace) Vol. 18 Issue 4 Pg. 550-9 (Apr 2016) ISSN: 1532-2092 [Electronic] England
• PMID: 26116830 (Publication Type: Comparative Study, Journal Article, Observational Study, Research Support, Non-U.S. Gov't)
• Copyright: © The Author 2015. Published by Oxford University Press on behalf of the European Society of Cardiology.

Chemical References

• Biomarkers
• Peptide Fragments
• pro-brain natriuretic peptide (1-76)
• Natriuretic Peptide, Brain

Topics

• Action Potentials
• Aged
• Biomarkers (blood)
• Bundle-Branch Block (diagnosis, mortality, physiopathology, therapy)
• Cardiac Resynchronization Therapy (adverse effects, methods, mortality)
• Chronic Disease
• Disease-Free Survival
• Echocardiography
• Electrocardiography
• Female
• Heart Conduction System (physiopathology)
• Heart Failure (diagnosis, mortality, physiopathology, therapy)
• Heart Ventricles (physiopathology)
• Humans
• Kaplan-Meier Estimate
• Male
• Middle Aged
• Natriuretic Peptide, Brain (blood)
• Peptide Fragments (blood)
• Predictive Value of Tests
• Prospective Studies
• Recovery of Function
• Risk Factors
• Stroke Volume
• Time Factors
• Treatment Outcome
• Ventricular Function, Left
• Ventricular Function, Right