Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Electrophysiology of Normal Cardiac Rhythm01:19

Electrophysiology of Normal Cardiac Rhythm

9.9K
The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase...
9.9K
Electrocardiogram Fundamentals01:28

Electrocardiogram Fundamentals

1.7K
Introduction
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin...
1.7K
Electrocardiogram01:29

Electrocardiogram

7.1K
An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
7.1K
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias01:25

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

716
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...
716
ECG Interpretation of Rhythms01:24

ECG Interpretation of Rhythms

15.9K
An electrocardiogram (ECG)graphically represents the heart's electrical activity on ECG paper or a monitor.
Components of the Electrocardiogram
The primary components of a normal ECG waveform in Normal sinus rhythm(NSR) include the P wave, PR interval, QRS complex, ST segment, T wave, and occasionally a U wave.
ECG waveforms are divided by vertical and horizontal lines at standard intervals.
The horizontal axis measures time and rate, and the vertical axis measures amplitude or voltage....
15.9K
Dysrhythmias V: Evaluating Dysrhythmias01:30

Dysrhythmias V: Evaluating Dysrhythmias

423
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...
423

You might also read

Related Articles

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

Sort by
Same author

Risk Factors and Prevention of Cancer and CVDs: A Chicken and Egg Situation.

Journal of clinical medicine·2025
Same author

A Look at Primary and Secondary Prevention in the Elderly: The Two Sides of the Same Coin.

Journal of clinical medicine·2024
Same author

Cardio-oncology rehabilitation: are we ready?

European heart journal supplements : journal of the European Society of Cardiology·2024
Same author

The Mediterranean Diet, Its Microbiome Connections, and Cardiovascular Health: A Narrative Review.

International journal of molecular sciences·2024
Same author

Relationship Between Mediterranean Diet, Cardiovascular Risk Factors, and Meningiomas: A Retrospective Study.

Anticancer research·2023
Same author

Experimental study on physical exercise in diabetes: pathophysiology and therapeutic effects.

European journal of translational myology·2023

Related Experiment Video

Updated: Mar 2, 2026

Measuring Cardiac Autonomic Nervous System ANS Activity in Children
09:45

Measuring Cardiac Autonomic Nervous System ANS Activity in Children

Published on: April 29, 2013

21.5K

Age- and sex-based reference ranges for non-invasive ventricular repolarisation parameters.

Annabella Braschi1, Maurizio G Abrignani2, Vincenzo C Francavilla1

  • 1Department of Internal and Specialistic Medicine, Palermo University Hospital, Palermo, Italy.

International Journal of Clinical Practice
|May 17, 2017
PubMed
Summary

Ventricular repolarisation markers like QT and Tpeak-Tend show significant age and sex variations. Understanding these normal reference intervals is crucial for accurate clinical diagnosis in all age groups.

More Related Videos

Noninvasive Electrocardiography in the Perinatal Mouse
04:36

Noninvasive Electrocardiography in the Perinatal Mouse

Published on: June 12, 2020

6.8K
In Vivo Surface Electrocardiography for Adult Zebrafish
09:13

In Vivo Surface Electrocardiography for Adult Zebrafish

Published on: August 1, 2019

14.9K

Related Experiment Videos

Last Updated: Mar 2, 2026

Measuring Cardiac Autonomic Nervous System ANS Activity in Children
09:45

Measuring Cardiac Autonomic Nervous System ANS Activity in Children

Published on: April 29, 2013

21.5K
Noninvasive Electrocardiography in the Perinatal Mouse
04:36

Noninvasive Electrocardiography in the Perinatal Mouse

Published on: June 12, 2020

6.8K
In Vivo Surface Electrocardiography for Adult Zebrafish
09:13

In Vivo Surface Electrocardiography for Adult Zebrafish

Published on: August 1, 2019

14.9K

Area of Science:

  • Cardiology
  • Physiology

Background:

  • Electrocardiographic parameters indirectly assess ventricular repolarisation homogeneity.
  • Accurate discrimination between normal and abnormal values is essential for clinical decision-making.
  • A lack of consensus on normal cut-off values necessitates establishing reference intervals.

Purpose of the Study:

  • To document reference intervals for ventricular repolarisation markers across all age groups in a healthy population.
  • To provide age- and sex-percentile tables for easy clinical application.
  • To aid in differentiating normal from pathological values in clinical practice.

Main Methods:

  • Evaluated repolarisation markers in 606 sex-matched participants (1 day-94 years).
  • Subjects underwent a 12-lead resting electrocardiogram.
  • Measured parameters included QT, corrected QT, QTpeak, Tpeak-Tend, Tpeak-Tend dispersion, Tpeak-Tend/QT, and QTpeak/QT ratios.

Main Results:

  • Age demonstrated a relationship with QTpeak, Tpeak-Tend, QT, and QTc intervals.
  • In children, QTpeak, Tpeak-Tend, and QT intervals increased linearly with age.
  • Significant sex differences in Tpeak-Tend intervals were observed in adolescents and adults.

Conclusions:

  • Repolarisation parameters exhibit age- and sex-based variations.
  • These variations are critical for distinguishing normal from pathological electrocardiographic findings.
  • Established reference intervals facilitate accurate clinical interpretation.