Strain-based staging as a unifying concept in cardiac resynchronization therapy
Jürgen Duchenne1,2,3,4, Simon Calle5, Ivan Stankovic6
1Department of Cardiovascular Sciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium.
Insights
Left bundle branch block (LBBB) septal strain patterns predict cardiac resynchronization therapy (CRT) outcomes. Lower strain stages indicate reduced benefits, potentially due to myocardial scar, highlighting LBBB patterns for personalized CRT.
Area of Science:
- Cardiology
- Cardiac Electrophysiology
- Medical Imaging
Background:
- Left bundle branch block (LBBB) septal strain patterns are linked to left ventricular (LV) reverse remodeling post-cardiac resynchronization therapy (CRT).
- The prognostic value of LBBB strain patterns and their impact on CRT outcomes, including comparison with conservative treatment, requires further investigation.
- Understanding the interplay between LBBB strain patterns, myocardial scar, and CRT response is crucial for optimizing patient selection and treatment strategies.
Purpose of the Study:
- To validate the prognostic significance of LBBB septal strain patterns in patients undergoing CRT.
- To investigate the impact of LBBB strain patterns on clinical outcomes and volumetric response in CRT recipients.
- To explore the relationship between LBBB strain patterns, myocardial scar burden, and CRT efficacy in CRT-eligible patients receiving conservative treatment.
Main Methods:
- A multicentre study involving 267 CRT patients who underwent pre-implantation speckle-tracking strain analysis.
- Cardiac magnetic resonance imaging was performed in 155 CRT patients to assess myocardial scar.
- Comparison between CRT-treated patients and 116 CRT-eligible conservatively treated patients, categorizing LBBB septal strain curves into five stages (LBBB-0 to LBBB-4).
Main Results:
- A stepwise improvement in volumetric response and survival was observed across LBBB stages in CRT recipients (P < 0.001 and P = 0.002, respectively).
- Myocardial scar, present in 52% of CRT patients, showed an inverse correlation with LBBB stages (P = 0.003).
- LBBB stages independently predicted volumetric response (OR 2.30, P < 0.001) and survival (HR 0.64, P = 0.038), whereas scar burden did not. Survival benefits were significantly greater in CRT-treated versus conservatively treated patients, especially in higher LBBB stages.
Conclusions:
- LBBB septal strain stages serve as independent predictors of CRT outcomes.
- Lower LBBB strain stages are associated with attenuated CRT benefits, potentially mediated by higher myocardial scar burden.
- This LBBB strain classification offers a valuable framework for understanding LBBB pathophysiology and optimizing CRT response.
Aims:
Left bundle branch block (LBBB) septal strain patterns are associated with left ventricular (LV) reverse remodelling after cardiac resynchronization therapy (CRT). However, their prognostic value and impact in patients undergoing CRT, as well as in CRT-eligible patients receiving conservative treatment, remains underexplored. This study aimed to validate the prognostic significance of LBBB strain patterns and elucidate the mechanisms underlying CRT response by evaluating their interaction with myocardial scar and clinical outcomes.
Methods And Results:
In this multicentre study, 267 CRT patients underwent pre-implantation speckle-tracking strain analysis, with 155 also undergoing cardiac magnetic resonance imaging. CRT-treated patients were compared with 116 CRT-eligible conservatively treated patients. LBBB septal strain curves were categorized into five stages (LBBB-0 to LBBB-4). Endpoints included all-cause mortality, heart transplantation, and volumetric response in CRT recipients.CRT outcomes showed a stepwise improvement across LBBB stages in volumetric response (P < 0.001) and survival (log-rank P = 0.002). Myocardial scar, present in 52% of CRT patients, inversely correlated with LBBB stages (P = 0.003). After multivariable adjustment, LBBB stages independently predicted volumetric response (OR 2.30, P < 0.001) and survival (HR 0.64, P = 0.038), while scar burden did not. Survival benefits were greater in CRT-treated patients than in conservatively treated patients, ranging from HR 1.42 (P = 0.436) in LBBB-0 to HR 16.49 (P < 0.001) in LBBB-4.
Conclusion:
LBBB strain stages independently predict CRT outcomes, with lower stages associated with attenuated benefits, possibly due to higher scar burden. This classification provides a framework for understanding LBBB pathophysiology and CRT response.
More Related Videos
10:17Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
Published on: April 11, 2025
06:57Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction
Published on: January 31, 2019
Related Concept Videos
01:30Heart Failure IV: Classification and Diagnostic Evaluation
01:29Cardiomyopathy IV: Restrictive Cardiomyopathy