True left bundle branch block and long-term mortality in cardiac resynchronisation therapy patients

Area of Science:

• Cardiology
• Electrophysiology
• Medical Diagnostics

Background:

• Left bundle branch block (LBBB) is a key factor in qualifying and predicting outcomes for cardiac resynchronisation therapy (CRT).
• Evaluating LBBB definitions is crucial for optimizing CRT patient selection and treatment efficacy.

Purpose of the Study:

• To assess the long-term mortality and morbidity in CRT patients using the novel Perrin criteria for LBBB.
• To compare the predictive value of the Perrin criteria against existing definitions for LBBB in CRT.

Main Methods:

• A longitudinal cohort study of 552 consecutive CRT patients.
• Analysis of all-cause death and heart failure hospitalisation as primary and secondary endpoints.
• Electrocardiograms were classified using Perrin, CRT guidelines, and Strauss criteria.

Main Results:

• The Perrin criteria identified "true LBBB" in 38.9% of patients, compared to 62.3% by Strauss criteria.
• Over nine years, 232 deaths and 292 combined events occurred.
• The Perrin criteria showed lower predictive accuracy for survival (C-statistics) than Strauss criteria, though both definitions predicted mortality.

Conclusions:

• The Perrin "true LBBB" criteria may not be optimal for selecting CRT candidates.
• These criteria might exclude patients who benefit from CRT despite incomplete LBBB.
• Further research is needed to refine LBBB definitions for improved CRT patient selection.