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

Decreased pulse rate

Decreased pulse rate

Bradycardia is a medical condition in which the heart rate is slower than normal. It occurs when the heart's natural pacemaker, the sinus node, generates slower electrical impulses than the standard rhythm. In adults, bradycardia is diagnosed when the pulse rate falls below 60 beats per minute, indicating a deviation from the normal heart rate range.
There are specific risk factors that can elevate the likelihood of developing bradycardia. Advanced age is a significant factor, with bradycardia...

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...

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...

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias

Arrhythmias are disturbances in the heart's rhythm that lead to abnormal heartbeats. These irregularities can originate from different parts of the heart and are classified based on their origin and nature.
Types of Arrhythmias
Sinus Node Arrhythmias
Sinus Bradycardia: Originating from the sinoatrial (SA) node, sinus bradycardia involves slower impulses, resulting in a heart rate of less than 60 beats per minute (bpm). Causes include sleep, vagal stimulation, beta-blockers, hypothyroidism, and...

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.

You might also read

Related Articles

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

Sort by

Same author

A Novel Surgical Approach for Double-Outlet Right Ventricle With Noncommitted Ventricular Septal Defect.

Annals of thoracic surgery short reports·2026

Same author

Early detection and successful containment of Staphylococcus haemolyticus ST29 in a Swiss neonatal unit.

The Journal of hospital infection·2026

Same author

Correction: Family involvement along the care continuum for small and sick newborns - attitudes and skills of healthcare providers in Ghana.

Journal of health, population, and nutrition·2026

Same author

Parenteral treprostinil in paediatric pulmonary arterial hypertension: a systematic review and meta-analysis.

European respiratory review : an official journal of the European Respiratory Society·2026

Same author

Macitentan in Pediatric Pulmonary Arterial Hypertension (TOMORROW): A Randomized Clinical Trial.

The Journal of pediatrics·2026

Same author

The Pulmonary Hypertension Global Patient Survey: Physical and Psychosocial Impacts on Health-Related Quality of Life.

Pulmonary circulation·2026

Search research articles

Related Experiment Video

Updated: Jun 26, 2026

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance

Published on: March 21, 2013

Vagal bradycardia at term.

Cristina Delcò¹, Maurice Beghetti, Riccardo E Pfister

¹Department of the Child and Adolescent, University Hospital of Geneva and Geneva University, Switzerland.

Acta Paediatrica (Oslo, Norway : 1992)

|February 3, 2009

Summary

Vagal hyper-reflectivity (VHR) in newborns causes severe bradycardia. Atropine effectively treats VHR, resolving bradycardic events and enabling safe, early hospital discharge.

Area of Science:

Neonatal cardiology
Pediatric autonomic nervous system function

Background:

Severe bradycardic events and prolonged sinus pauses are concerning in term newborns.
Pathologic bradycardia is defined by specific heart rate and pause durations.

Observation:

A newborn presented with severe bradycardia and sinus pauses up to 5.4 seconds.
Specific causes were excluded, leading to a diagnosis of vagal hyper-reflectivity (VHR).
VHR is characterized by parasympathetic activity overriding sympathetic activity.

Findings:

Vagal hyper-reflectivity is a functional, transitional anomaly of autonomic tone in early infancy.
This condition can necessitate extended monitoring and delayed hospital discharge.
Atropine treatment led to immediate resolution of bradycardic events in this case.

More Related Videos

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

Quantitative Autonomic Testing

Quantitative Autonomic Testing

Published on: July 19, 2011

Related Experiment Videos

Last Updated: Jun 26, 2026

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance

Published on: March 21, 2013

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

Quantitative Autonomic Testing

Quantitative Autonomic Testing

Published on: July 19, 2011

Implications:

Atropine is an effective treatment for symptomatic bradycardia due to VHR.
Prompt treatment allows for early and safe discharge of affected newborns.
Understanding VHR is crucial for managing rare neonatal bradycardia.