Related Experiment Video

Updated: Aug 16, 2026

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
12:45

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

Area of left ventricular regional conduction delay and preserved myocardium predict responses to cardiac

Hung-Fat Tse1, Kathy Lf Lee, Siu-Hong Wan

  • 1Cardiology Division, Department of Medicine, the University of Hong Kong, Queen Mary Hospital, Hong Kong, China. hftse@hkucc.hku.hk

Journal of Cardiovascular Electrophysiology
|July 30, 2005
PubMed

Insights

Electromechanical mapping can predict response to cardiac resynchronization therapy (CRT). A larger area of late endocardial activation and preserved myocardium indicates better acute hemodynamic improvement during left ventricular pacing.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Devices

Background:

  • Many patients with dilated cardiomyopathy and left bundle branch block (LBBB) do not benefit from cardiac resynchronization therapy (CRT).
  • Predicting response to CRT is crucial for optimizing patient outcomes.

Purpose of the Study:

  • To determine if electromechanical properties of the myocardium predict acute hemodynamic improvement during left ventricular (LV) pacing in patients with LBBB.
  • To identify predictors of CRT response using advanced mapping techniques.

Main Methods:

  • 10 patients with dilated cardiomyopathy and LBBB underwent 3D electromechanical endocardial mapping.
  • Assessed endocardial activation time (Endo-AT), unipolar voltage, and local linear shortening during sinus rhythm.
  • Measured changes in LV+dP/dtmax during LV stimulation at various coronary sinus sites and atrioventricular delays.

Main Results:

  • No significant correlation was found between CRT response and LV ejection fraction, baseline LV+dP/dtmax, total LV Endo-AT, or QRS duration changes.
  • A significant positive correlation existed between hemodynamic improvement (%DeltadP/dtmax) and the percentage of LV area with late Endo-AT (r=0.97) and preserved myocardium (r=0.81).
  • Patients with >20% late Endo-AT and >30% preserved myocardium showed a fivefold better acute hemodynamic response.

Conclusions:

  • A larger area of late endocardial activation and preserved LV myocardium, identified by electromechanical mapping, predicts better acute systolic performance improvement during LV stimulation.
  • These findings suggest electromechanical mapping can help select patients who will benefit from CRT.
Abstract

More Related Videos

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System10:17

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System

Published on: April 11, 2025

Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction06:57

Ablation 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

Cardiomyopathy IV: Restrictive Cardiomyopathy01:29

Cardiomyopathy IV: Restrictive Cardiomyopathy

Restrictive cardiomyopathy (RCM) is a rare heart muscle disease characterized by impaired ventricular filling due to stiffened ventricular walls, leading to significant diastolic dysfunction.EtiologyRestrictive cardiomyopathy can arise from both inherited and acquired diseases, many of which are systemic. It is categorized into four main types: infiltrative, storage, non-infiltrative, and endomyocardial diseases.Infiltrative diseases, such as amyloidosis, lead to RCM by depositing amyloid...
Cardiomyopathy V: Interprofessional Care01:29

Cardiomyopathy V: Interprofessional Care

Managing cardiomyopathy involves addressing underlying or precipitating causes, treating heart failure with medications, and implementing dietary changes and a balanced exercise and rest regimen.Lifestyle ModificationsCardiomyopathy patients should adopt a low-sodium diet to reduce fluid retention and manage heart failure. A personalized exercise and rest plan helps maintain physical fitness without overstraining the heart. Avoiding alcohol and tobacco is essential to prevent further damage to...
Electrophysiology of Normal Cardiac Rhythm01:19

Electrophysiology of Normal Cardiac Rhythm

The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase of...