Left bundle branch block-induced dilated cardiomyopathy: Definitions, pathophysiology, and therapy
Catarina Amaral Marques1, Ana Laura Costa2, Elisabete Martins1
1Faculty of Medicine - University of Porto, Porto, Portugal; Department of Cardiology, Centro Hospitalar Universitário São João, Porto, Portugal.
Summary
Left bundle branch block (LBBB) can cause dilated cardiomyopathy (DCM). Early cardiac resynchronization therapy (CRT) may improve left ventricular function in LBBB-induced DCM (LBBB-iDCM) patients, but diagnostic criteria are lacking.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Research
Background:
- Left bundle branch block (LBBB) is common in heart failure (HF), especially with dilated cardiomyopathy (DCM).
- LBBB was historically viewed as a consequence of DCM.
- Recent observations suggest LBBB may induce DCM (LBBB-iDCM), a distinct entity.
Purpose of the Study:
- To review the pathophysiology of LBBB-induced dilated cardiomyopathy (LBBB-iDCM).
- To discuss current diagnostic criteria for LBBB-iDCM.
- To outline proposed therapeutic strategies for LBBB-iDCM.
Main Methods:
- Literature review of LBBB-iDCM pathophysiology.
- Analysis of proposed diagnostic criteria.
- Synthesis of current therapeutic approaches.
Main Results:
- Evidence supports LBBB-iDCM as a specific pathological entity.
- Patients with LBBB-iDCM may benefit from early cardiac resynchronization therapy (CRT).
- Definitive diagnostic criteria and therapeutic guidelines for LBBB-iDCM are currently absent.
Conclusions:
- LBBB-iDCM recognition has significant clinical implications for HF management.
- Early CRT may be a beneficial strategy for LBBB-iDCM.
- Further research is needed to establish universal diagnostic criteria and therapeutic protocols.
Keywords:
Bloqueio de ramo esquerdoCardiac resynchronization therapy (CRT)DessincronopatiaDessynchronopathyDilated cardiomyopathy (DCM)Left bundle branch block (LBBB)Left bundle branch block-induced dilated cardiomyopathy (LBBB-iDCM)Miocardiopatia dilatadaMiocardiopatia dilatada induzida por bloqueio de ramo esquerdoTerapia de ressincronização cardíaca
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