Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Conduction System of the Heart

Conduction System of the Heart

Autorhythmicity is a term that refers to the heart's inherent ability to generate electrical signals and instigate muscle contractions. This self-regulating conduction system within the heart consists of two key components: the pacemaker cells and specialized conducting cells.
The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...

Conduction System of the Heart

Conduction System of the Heart

The cardiac conduction system produces and transmits electrical impulses that prompt myocardial contraction, ensuring efficient heart function. This intricate system ensures that the heart beats in a coordinated and efficient manner, beginning with the atria and then the ventricles. The conduction system optimizes cardiac output by maintaining this precise sequence, which is crucial for adequate blood circulation.
This system relies on the unique properties of nodal and Purkinje cells:...

Specialized Characteristics of Cardiac Muscles

Specialized Characteristics of Cardiac Muscles

The primary role of cardiac muscles is to propel blood throughout the cardiovascular system. The cardiac muscle cells, or cardiomyocytes, exhibit specialized characteristics that allow them to perform this function.
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy reserves in...

Electrophysiology of Normal Cardiac Rhythm

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...

Dysrhythmias VI: Management of Dysrhythmias

Dysrhythmias VI: Management of Dysrhythmias

Dysrhythmia management involves a multifaceted approach, incorporating pharmacological treatments, medical procedures, surgical interventions, lifestyle modifications, and patient education.Pharmacological ManagementAntiarrhythmic Drugs:Class I (Sodium Channel Blockers): This class includes quinidine and procainamide, which reduce the speed of impulse conduction in the heart, stabilize the cardiac membrane, and control arrhythmias. Quinidine and procainamide are Class IA agents that prolong the...

Cardiomyopathy II: Dilated Cardiomyopathy

Cardiomyopathy II: Dilated Cardiomyopathy

Dilated cardiomyopathy, or DCM, is a progressive myocardial disorder characterized by ventricular chamber dilation and contractile dysfunction.EtiologyVarious factors can cause DCM, including hypertension and heavy alcohol intake, which contribute to the weakening and enlargement of the heart muscle. Viral infections, such as Coxsackievirus B, adenoviruses, and influenza, can lead to DCM by causing inflammation and damage to heart tissue. Certain chemotherapeutic agents, including daunorubicin,...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

The 'CIED Team' Approach to Device-Related Complications.

JACC. Case reports·2026

Same author

Spontaneous coronary artery dissection and sudden cardiac arrest: a reversible event or an indication for secondary prevention?

Journal of cardiovascular medicine (Hagerstown, Md.)·2026

Same author

Selective Use of Nonselective Beta-Blockers: A Tailored Antiarrhythmic Approach.

JACC. Clinical electrophysiology·2026

Same author

Catheter ablation vs. anti-arrhythmic drug therapy for ventricular tachycardia in ischaemic heart disease-Authors' reply.

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology·2026

Same author

Diversity, equity, and inclusion in arrhythmia care: a European Heart Rhythm Association survey.

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology·2026

Same author

Deep ensemble optimized models for probabilistic CTV breast segmentation.

Frontiers in artificial intelligence·2026

Search research articles

Related Experiment Video

Updated: May 15, 2026

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

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

Larger interventricular conduction time enhances mechanical response to resynchronization therapy.

Luigi Padeletti¹, Paolo Pieragnoli, Giuseppe Ricciardi

¹Institute of Internal Medicine and Cardiology, University of Florence, Florence, Italy. lpadeletti@interfree.it

Pacing and Clinical Electrophysiology : PACE

|January 12, 2013

Summary

Optimizing cardiac resynchronization therapy (CRT) involves finding the best left ventricular (LV) pacing site. Measuring right ventricular (RV)-to-LV conduction time helps identify optimal LV lead placement for improved systolic function.

More Related Videos

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

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

Published on: April 11, 2025

Programmed Electrical Stimulation in Mice

Programmed Electrical Stimulation in Mice

Published on: May 26, 2010

Related Experiment Videos

Last Updated: May 15, 2026

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

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

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

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

Published on: April 11, 2025

Programmed Electrical Stimulation in Mice

Programmed Electrical Stimulation in Mice

Published on: May 26, 2010

Area of Science:

Cardiology
Electrophysiology
Medical Devices

Background:

Left ventricular (LV) pacing site significantly impacts hemodynamic response in cardiac resynchronization therapy (CRT).
Current lead positioning in lateral or posterolateral cardiac veins may not be universally optimal.
Individualized LV lead placement is crucial for effective CRT.

Purpose of the Study:

To evaluate the relationship between right ventricular (RV)-to-LV conduction time and systolic function during CRT.
To assess if RV-to-LV conduction time can predict optimal LV pacing site.
To analyze changes in LV pressure-volume loops based on pacing site and AV delay.

Main Methods:

Utilized conductance catheter to measure LV pressure and volume in 10 patients during CRT implantation.
Systematically assessed four endocardial LV sites across four atrioventricular delays.
Measured RV-to-LV conduction time as the interval between spontaneous peak R waves from RV lead and LV catheter.

Main Results:

Optimal pacing site varied among patients.
Pacing at the site with maximum RV-to-LV conduction time yielded stroke volume improvement comparable to individually optimized sites (41 ± 17 mL vs 44 ± 18 mL, P = 0.266).
RV-to-LV conduction time positively correlated with increases in stroke volume (r = 0.537), stroke work (r = 0.642), and pressure-derivative maximum (r = 0.646).

Conclusions:

Optimal acute CRT response can be achieved by placing the LV lead at the site with maximum RV-to-LV conduction time.
A significant correlation exists between RV-to-LV conduction time and CRT-induced systolic function improvement.
RV-to-LV conduction time serves as a valuable predictor for LV lead positioning in CRT.