Related Experiment Video

Updated: Sep 21, 2026

High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation
09:17

High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation

Published on: July 29, 2011

Concealed arrhythmogenic syndromes: the hidden substrate of idiopathic ventricular fibrillation?

S G Priori1, C Napolitano, M Grillo

  • 1Molecular Cardiology, Fondazione Salvatore Maugeri, Via Ferrata 8, 27100 Pavia, Italy. spriori@fsm.it

Cardiovascular Research
|May 4, 2001
PubMed

Insights

Idiopathic ventricular fibrillation, a cause of sudden cardiac arrest without identifiable heart disease, may stem from genetic defects. Research suggests these genetic factors might be incompletely penetrant, explaining unexplained cardiac events.

Area of Science:

  • Cardiology
  • Genetics
  • Forensic Pathology

Background:

  • Sudden cardiac arrest (SCA) and cardiac arrest survivors often lack identifiable cardiac abnormalities.
  • Approximately 6-10% of SCA cases and similar percentages of sudden death victims show no structural heart disease.
  • These cases are termed 'idiopathic ventricular fibrillation' (IVF), with unknown causes.

Purpose of the Study:

  • To investigate the hypothesis that genetic defects underlie unexplained cases of cardiac arrest.
  • To explore the role of incompletely penetrant genetic factors in idiopathic ventricular fibrillation.

Main Methods:

  • Review of clinical evaluations in cardiac arrest survivors.
  • Analysis of autopsy data from sudden death victims.
  • Presentation of data supporting a genetic hypothesis for unexplained arrhythmias.

Main Results:

  • A significant percentage of cardiac arrest survivors and victims show no identifiable cardiac abnormalities.
  • This suggests a potential underlying cause beyond structural heart disease.
  • Data support the role of genetic factors in these unexplained events.

Conclusions:

  • Incompletely penetrant genetic defects are proposed as a cause for a subset of idiopathic ventricular fibrillation.
  • This research opens new avenues for understanding and diagnosing unexplained cardiac arrest.
  • Genetic testing may become crucial in evaluating patients with unexplained arrhythmias.

More Related Videos

Electrophysiological Assessment of Murine Atria with High-Resolution Optical Mapping08:19

Electrophysiological Assessment of Murine Atria with High-Resolution Optical Mapping

Published on: February 22, 2018

Dual-Dye Optical Mapping of Hearts from RyR2R2474S Knock-In Mice of Catecholaminergic Polymorphic Ventricular Tachycardia09:36

Dual-Dye Optical Mapping of Hearts from RyR2R2474S Knock-In Mice of Catecholaminergic Polymorphic Ventricular Tachycardia

Published on: December 22, 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 I: Introduction01:15

Dysrhythmias I: Introduction

Dysrhythmias refers to abnormalities in the heart's rhythm. They result from disruptions in the heart's electrical conduction system, which includes the sinoatrial(SA)node, atrioventricular(AV) node, the bundle of His, bundle branches, and Purkinje fibers.Definition and PathophysiologyDysrhythmias result from disorders of impulse formation, impulse conduction, or both. The heart contains specialized cells in the sinoatrial node, atrioventricular node, and the bundle of His and Purkinje fibers...
Dysrhythmias II: Classification of Tachyarrhythmias01:28

Dysrhythmias II: Classification of Tachyarrhythmias

Tachyarrhythmias are a type of dysrhythmia where the heart rate exceeds 100 beats per minute. Here are some common types of tachyarrhythmias:Sinus TachycardiaSinus tachycardia originates from increased impulses from the sinus node, leading to an elevated heart rate. It is often triggered by stress, fever, or exercise.Patients may experience palpitations, a sensation of a racing heart, dizziness, and chest discomfort.Causes and Risk Factors: Common causes include physical exertion, emotional...
Dysrhythmias III: Characteristics of Dysrhythmias01:29

Dysrhythmias III: Characteristics of Dysrhythmias

Dysrhythmias, also known as arrhythmias, are irregular heart rhythms that result from abnormal electrical activity in the heart, affecting its ability to circulate blood efficiently. Tachyarrhythmias, a subset of dysrhythmias, are characterized by abnormally fast heart rates exceeding 100 beats per minute. Here are some types of tachyarrhythmias with their distinct ECG features:Sinus Tachycardia:Sinus tachycardia presents a regular heart rhythm with an increased rate of 101-180 beats per minute.
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...