Related Experiment Video

Updated: Sep 9, 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

Approaches to experimental arrhythmias in heart failure

S M Cobbe1, M P Pye

  • 1Department of Medical Cardiology, Royal Infirmary, Glasgow, Scotland.

Therapie
|May 1, 1992
PubMed

Insights

Sudden cardiac death in heart failure is often caused by lethal ventricular arrhythmias. More research is needed to understand the complex mechanisms driving these arrhythmias, including myocardial alterations and neuroendocrine factors.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Heart Failure Research

Background:

  • Sudden cardiac death (SCD) constitutes a significant portion of mortality in heart failure patients, primarily due to lethal ventricular arrhythmias.
  • Despite clinical recognition, the underlying mechanisms of these arrhythmias in heart failure remain under-investigated experimentally.
  • Potential contributing factors include myocardial alterations, ventricular overload, and neuroendocrine activation.

Purpose of the Study:

  • To review and highlight the limited experimental studies on the mechanisms of lethal ventricular arrhythmias in heart failure.
  • To discuss potential arrhythmogenic mechanisms beyond primary myocardial damage, such as ventricular overload and neuroendocrine activation.
  • To identify gaps in knowledge and suggest future research directions for understanding arrhythmias in heart failure.

Main Methods:

  • Review of existing clinical and experimental literature on heart failure and ventricular arrhythmias.
  • Discussion of proposed arrhythmogenic mechanisms, including reentry and triggered activity in ventricular hypertrophy.
  • Analysis of findings from experimental models and limited in vivo human studies.

Main Results:

  • Experimental studies on heart failure models have yielded inconsistent results regarding electrophysiological modifications and their link to arrhythmias.
  • Some human in vivo studies suggest prolonged and dispersed repolarization in patients with idiopathic dilated cardiomyopathy undergoing transplantation.
  • The precise roles of ventricular overload and neuroendocrine activation in arrhythmia development require further elucidation.

Conclusions:

  • Lethal ventricular arrhythmias are a major cause of sudden cardiac death in heart failure.
  • Current understanding of the electrophysiological mechanisms driving these arrhythmias is incomplete.
  • Further experimental and clinical investigations are crucial to clarify the complex mechanisms underlying arrhythmias in heart failure.

More Related Videos

Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System06:40

Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System

Published on: May 22, 2018

A Model of Long-Term Ventricular Fibrillation in Isolated Rat Hearts07:56

A Model of Long-Term Ventricular Fibrillation in Isolated Rat Hearts

Published on: February 17, 2023

Related Concept Videos

Mechanism of Cardiac Arrhythmias01:28

Mechanism of Cardiac Arrhythmias

Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.
Disturbances in Heart Rhythm01:29

Disturbances in Heart Rhythm

Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
Dysrhythmias V: Evaluating Dysrhythmias01:30

Dysrhythmias V: Evaluating Dysrhythmias

Dysrhythmias, also known as arrhythmias, are disturbances in the heart's rhythm that range from benign to life-threatening. A thorough evaluation is crucial for appropriate management and involves a comprehensive medical history, physical examination, and various diagnostic tests.Medical HistorySymptoms: Collect detailed information on palpitations, dizziness, syncope, chest pain, and fatigue. Note their onset, frequency, and triggers.Previous Cardiac Issues: Document any history of heart...
Dysrhythmias VI: Management of Dysrhythmias01:25

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...
Heart Failure VI: Adjunct Therapies01:22

Heart Failure VI: Adjunct Therapies

Additional therapies for treating patients with heart failure (HF) may include procedural interventions, supplemental oxygen, the management of sleep disorders, and nutritional therapy.Procedural InterventionsImplantable Cardioverter-Defibrillator: For patients at risk of life-threatening arrhythmias due to severe left ventricular dysfunction, an Implantable Cardioverter-Defibrillator (ICD) can detect and terminate these arrhythmias, preventing sudden cardiac death and improving survival rates.
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias01:25

ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias

Arrhythmia is a condition characterized by an irregular heart rhythm, with ECG changes that differ based on its origin and nature. The types of arrhythmias discussed below include atrial, junctional, and ventricular arrhythmias.Atrial ArrhythmiasPremature Atrial Complexes (PACs): PACs are early atrial beats caused by stress, caffeine, alcohol, electrolyte imbalances, hypoxia, hyperthyroidism, or certain medications (e.g., bronchodilators and decongestants). The ECG shows early P waves with an...