Related Experiment Video

Updated: Jun 4, 2025

Scanning Electron Microscopy of Macerated Tissue to Visualize the Extracellular Matrix
10:21

Scanning Electron Microscopy of Macerated Tissue to Visualize the Extracellular Matrix

Published on: June 14, 2016

10.0K

Relationship between myocardial fibrosis and left bundle branch block. Does it exist?

Elena Rimskaya1, Olga Aparina1, Olga Stukalova1

  • 1Chazov National Medical Research Center of Cardiology 121552, Academician Chazov str., 15a, Moscow, Russia.

Cardiovascular Pathology : the Official Journal of the Society for Cardiovascular Pathology
|January 2, 2025
PubMed

Insights

Left bundle branch block (LBBB) in dilated cardiomyopathy (DCM) patients is not caused by focal or interstitial fibrosis. Diffuse inflammation may worsen systolic dysfunction, while increased fibrosis in idiopathic LBBB suggests a developing DCM.

Area of Science:

  • Cardiology
  • Cardiac Imaging
  • Pathology

Background:

  • Left bundle branch block (LBBB) is a common finding in patients with dilated cardiomyopathy (DCM).
  • The underlying substrate and relationship between cardiac fibrosis and LBBB in DCM remain incompletely understood.
  • Differentiating LBBB causes is crucial for prognosis and management.

Purpose of the Study:

  • To investigate the association between focal and diffuse left ventricular (LV) fibrosis and LBBB in patients with DCM.
  • To compare fibrosis patterns in DCM patients with and without LBBB, and in those with idiopathic LBBB.

Main Methods:

  • Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) was used to assess focal fibrosis (core scar and gray zone) and diffuse fibrosis (diffuse intensity ratio - DIR).
  • Endomyocardial biopsy (EMB) quantified collagen volume fraction (CVF) in a subset of patients.
  • Study included DCM patients with LBBB (DCM-LBBB), DCM without LBBB (DCM-nonLBBB), idiopathic LBBB, and healthy volunteers (HV).

Main Results:

  • No significant difference in focal or diffuse fibrosis was found between DCM-LBBB and DCM-nonLBBB patients.
  • CVF correlated with DIR, supporting DIR as a measure of diffuse fibrosis.
  • Patients with idiopathic LBBB showed higher DIR values compared to HV, suggesting underlying diffuse myocardial changes.

Conclusions:

  • Focal and interstitial fibrosis are not associated with LBBB in DCM.
  • Diffuse inflammation in DCM-LBBB may contribute to systolic dysfunction but does not cause LBBB.
  • Increased interstitial fibrosis in idiopathic LBBB may indicate a latent process leading to DCM development.
Abstract

Keywords:
Cardiovascular magnetic resonanceDilated cardiomyopathyEndomyocardial biopsyLate gadolinium enhancementLeft bundle branch block

More Related Videos

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing12:45

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing

Published on: December 11, 2017

10.4K
Left Coronary Artery Ligation: A Surgical Murine Model of Myocardial Infarction05:48

Left Coronary Artery Ligation: A Surgical Murine Model of Myocardial Infarction

Published on: August 9, 2022

4.2K

Related Concept Videos

Imbalances in Cardiac Output01:26

Imbalances in Cardiac Output

The heart's primary function is to pump blood throughout the body, maintaining a balance between blood sent out (cardiac output) and blood returning (venous return). If this balance is disrupted, it can result in congestive heart failure (CHF), a severe condition where the heart becomes an inefficient pump, leading to inadequate blood circulation.
CHF can occur due to the failure of either side of the heart. Left-side failure leads to pulmonary congestion—the right side continues to send...
1.3K
Pathophysiology of Heart Failure01:17

Pathophysiology of Heart Failure

Heart failure (HF) is a progressive syndrome involving ventricles that leads to inadequate cardiac output. It can be classified based on location and output or ejection fraction. Ejection fraction (EF) is an essential measurement in the diagnosis and surveillance of HF. Reduced EF corresponds to systolic heart failure (HFrEF). However, HF with preserved ejection fraction (HFpEF) is becoming increasingly prevalent. Also known as diastolic HF, this form of HF is related to aging. The...
1.5K