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

Disturbances in Heart Rhythm

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...

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.

Dysrhythmias III: Characteristics of Dysrhythmias

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.

Pathophysiology of Heart Failure

Pathophysiology of Heart Failure

Heart failure (HF) is a progressive syndrome involving ventricles that leads to inadequate cardiac output. It can be classified based on location and output or ejection fraction. Ejection fraction (EF) is an essential measurement in the diagnosis and surveillance of HF. Reduced EF corresponds to systolic heart failure (HFrEF). However, HF with preserved ejection fraction (HFpEF) is becoming increasingly prevalent. Also known as diastolic HF, this form of HF is related to aging. The...

Dysrhythmias IV: Characteristics of Bradyarrhythmias

Dysrhythmias IV: Characteristics of Bradyarrhythmias

Bradyarrhythmias are cardiac rhythm disorders characterized by a slower-than-normal heart rate, typically defined as fewer than 60 beats per minute. Some of which are discussed here:Sinus BradycardiaSinus bradycardia presents a heart rate lower than 60 beats per minute, with a regular rhythm originating from the SA node. The ECG typically shows normal P waves preceding each QRS complex, a normal PR interval (0.12 to 0.20 seconds), and a normal QRS duration (0.06 to 0.10 seconds).First-Degree AV...

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...

You might also read

Related Articles

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

Sort by

Same author

Prospective Validation of the Movement Disorder Society Prodromal Multiple System Atrophy Criteria in Pure Autonomic Failure.

Movement disorders : official journal of the Movement Disorder Society·2026

Same author

Cardiac Sympathetic Neuroimaging in Autonomic Synucleinopathies: <sup>123</sup>I-Metaiodobenzylguanidine and <sup>18</sup>F-Dopamine.

Movement disorders clinical practice·2026

Same author

Putamen Dopamine Synthesis, Vesicular Storage, and Metabolism in Patients With Parkinson Disease.

Neurology·2026

Same author

Catecholamine metabolism revisited: From neurochemistry to integrative physiology and pathophysiology.

Physiological reviews·2026

Same author

Central noradrenergic deficiency in post-infectious chronic fatigue: neurobehavioral correlates.

Brain communications·2026

Same author

Distinct Sympathoneural and Cardiovagal Domains of Arterial Baroreflex Function in Autonomic Synucleinopathies.

Research square·2026

Search research articles

Related Experiment Video

Updated: Jun 17, 2026

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

Published on: February 17, 2018

Cardiac ectopy in chronic autonomic failure.

David S Goldstein¹

¹Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive MSC-1620, Building 10 Room 5N220, Bethesda, MD 20892-1620, USA. goldsteind@ninds.nih.gov

Clinical Autonomic Research : Official Journal of the Clinical Autonomic Research Society

|December 17, 2009

Summary

Patients with chronic autonomic failure (CAF) experience a higher prevalence of atrial ectopy. This cardiac condition may worsen orthostatic hypotension and increase the risk of falls and syncope.

More Related Videos

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

Related Experiment Videos

Last Updated: Jun 17, 2026

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

Published on: February 17, 2018

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

Area of Science:

Cardiology
Neurology
Autonomic Nervous System

Background:

Chronic autonomic failure (CAF) encompasses conditions like Parkinson disease (PD), multiple system atrophy (MSA), and pure autonomic failure (PAF).
CAF is characterized by baroreflex failure, neurogenic orthostatic hypotension (NOH), and supine hypertension.
This physiological state may predispose individuals to cardiac ectopy, potentially leading to syncope and falls.

Purpose of the Study:

To investigate the association between chronic autonomic failure (CAF) and an increased prevalence of cardiac ectopy.
To determine if patients with NOH exhibit a higher incidence of arrhythmias compared to controls.

Main Methods:

A retrospective review of electrocardiogram, heart rate, and blood pressure recordings from 97 CAF patients and 82 control subjects.
Patients included those with PD + NOH, MSA, and PAF; controls included PD without NOH, non-parkinsonian patients, and healthy volunteers.
Cardiac ectopy was defined as the presence of at least two premature beats or an arrhythmia.

Main Results:

Atrial ectopy was significantly more prevalent in CAF patients (PD + NOH: 74%, MSA: 68%, PAF: 63%) compared to controls (PD without NOH: 28%, other controls: 24%).
Atrial ectopy correlated with age, supine systolic pressure, orthostatic systolic pressure fall, baroreflex-cardiovagal gain, and plasma norepinephrine levels.
In some cases, atrial ectopy was linked to hypotension after the Valsalva maneuver and sudden loss of consciousness due to atrial flutter/fibrillation.

Conclusions:

Patients with CAF exhibit a notably high frequency of atrial ectopy.
This increased ectopy may interact with baroreflex failure, exacerbating morbidity associated with orthostatic hypotension.
Further research is warranted to explore the clinical implications of atrial ectopy in CAF.