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

Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers

Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers

Adrenergic stimulation generally impacts cardiac rate and rhythm. Specifically, stimulation of the β-adrenoceptors triggers an increase in intracellular calcium ion influx and pacemaker currents, which may cause arrhythmias. Catecholamines like adrenaline also demonstrate β2-adrenoceptor-mediated hypokalemia, impacting cardiac action potential and disrupting the normal cardiac rhythm. Class II antiarrhythmic drugs are β-adrenoceptor antagonists or β-blockers, which indirectly block calcium...

Mechanism of Cardiac Arrhythmias

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.

Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers

Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers

Class I antiarrhythmic drugs are used to treat various types of arrhythmias or irregular heart rhythms. These drugs block the sodium (Na+) channels in the cardiac cells, thereby affecting the movement of electrical impulses across the heart. Class I antiarrhythmic drugs are divided into three subgroups: Class IA, Class IB, and Class IC, each with distinct mechanisms of action and effects on the heart.
Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...

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...

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

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...

Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers

Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers

Class III antiarrhythmic drugs are a group of medications that can prolong action potentials in the heart. They achieve this by blocking potassium channels or enhancing inward currents from sodium channels. However, these drugs have a unique property of "reverse use-dependence," which is most pronounced at slower heart rates and can lead to torsades de pointes—a specific type of arrhythmia. However, it is essential to note that excessive QT interval prolongation—a measure of the heart's...

You might also read

Related Articles

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

Sort by

Same author

Surgical outcomes in gallbladder cancer: evidence from the UK nationwide CAPBIL study.

HPB : the official journal of the International Hepato Pancreato Biliary Association·2026

Same author

Association between hypertension phenotypes and aortic valve peak velocity: a potential tool for identifying white-coat hypertension.

Hypertension research : official journal of the Japanese Society of Hypertension·2026

Same author

Mitral Transcatheter Edge-to-Edge Repair in Non-Surgical Candidates with Hypertrophic Obstructive Cardiomyopathy: Clip It, or Ablate It?

Journal of cardiovascular development and disease·2026

Same author

Pulmonary Embolism Associated With Pneumomediastinum and Pneumoperitoneum After Laparoscopic Myomectomy: A Case Report and Literature Review.

Cureus·2026

Same author

Balloon-Assisted Translocation of the Mitral Anterior Leaflet to Prevent Outflow Tract Obstruction During TMVR: The BATMAN Registry.

JACC. Cardiovascular interventions·2026

Same author

Percutaneous Transhepatic Endobiliary Microwave Ablation Before Stenting for Malignant Obstructive Jaundice: Evidence Synthesis and Preliminary Technical Experience.

Medicina (Kaunas, Lithuania)·2026

Search research articles

Related Experiment Video

Updated: Jun 29, 2026

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

Published on: April 5, 2011

Ventricular arrhythmias and antioxidative medication: experimental study.

Aggeliki Karahaliou¹, Christos Katsouras, Vasileios Koulouras

¹Intensive Care Unit, University Hospital of Ioannina, Greece. dvardakas@hotmail.com

Hellenic Journal of Cardiology : HJC = Hellenike Kardiologike Epitheorese

|October 14, 2008

Summary

Combination therapy with vitamin C and deferoxamine significantly reduced ventricular arrhythmias in a sheep model. This antioxidant and iron-binding agent combination offers protection against ischemia-reperfusion and blood pressure elevation-induced arrhythmias.

More Related Videos

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

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

Published on: February 17, 2023

Transesophageal Atrial Burst Pacing for Atrial Fibrillation Induction in Rats

Transesophageal Atrial Burst Pacing for Atrial Fibrillation Induction in Rats

Published on: February 14, 2022

Related Experiment Videos

Last Updated: Jun 29, 2026

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

Published on: April 5, 2011

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

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

Published on: February 17, 2023

Transesophageal Atrial Burst Pacing for Atrial Fibrillation Induction in Rats

Transesophageal Atrial Burst Pacing for Atrial Fibrillation Induction in Rats

Published on: February 14, 2022

Area of Science:

Cardiology
Pharmacology
Biochemistry

Background:

Reperfusion arrhythmias are linked to free radicals.
Blood pressure elevation-induced arrhythmias stem from contraction-excitation feedback.
Investigating novel antiarrhythmic strategies is crucial for cardiovascular health.

Purpose of the Study:

To evaluate the antiarrhythmic efficacy of vitamin C (antioxidant) and deferoxamine (iron-binding agent).
To assess the combined effect of vitamin C and deferoxamine against induced arrhythmias.
To elucidate the mechanisms underlying reperfusion and blood pressure elevation-induced arrhythmias.

Main Methods:

A randomized controlled trial involving 30 anesthetized sheep.
Induction of ventricular arrhythmias via ischemia-reperfusion and blood pressure elevation.
Intravenous administration of saline, vitamin C, deferoxamine, or their combination.

Main Results:

Ventricular tachycardia/fibrillation (VT/VF) occurred in 100% of control and deferoxamine-only groups.
VT/VF incidence was 75% in the vitamin C group and 37.5% in the combination group.
The combination therapy demonstrated a statistically significant reduction in VT/VF compared to controls (p < 0.03).

Conclusions:

Intravenous vitamin C and deferoxamine combination therapy provides protection against VT/VF.
Deferoxamine alone showed no protective effect against arrhythmias.
The antiarrhythmic role of vitamin C alone requires further clarification.