Related Experiment Video

Updated: Aug 23, 2026

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
08:28

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

Exercise-induced changes in QT interval duration and dispersion in patients with isolated myocardial bridging

Irfan Barutcu1, Alpay Turan Sezgin, Hakan Gullu

  • 1Kocatepe Heart Education and Research Hospital, Department of Cardiology, Afyon, Turkey. irfanbarutcu@yahoo.com

International Journal of Cardiology
|April 20, 2004
PubMed

Insights

Myocardial bridging (MB) patients show increased QT dispersion after exercise, suggesting potential exercise-induced ischemia. This finding highlights MB as a factor in cardiovascular events.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Diagnostic Imaging

Background:

  • Isolated myocardial bridging (MB) is often underestimated but linked to cardiovascular events.
  • Assessing exercise-induced electrocardiographic (ECG) changes and arrhythmia susceptibility in MB patients is crucial.

Purpose of the Study:

  • To evaluate exercise-induced ECG alterations in patients with myocardial bridging.
  • To determine if myocardial bridging increases susceptibility to arrhythmias during exercise.

Main Methods:

  • 21 patients with proven MB and 25 controls underwent a Bruce protocol exercise test.
  • QT interval duration and dispersion were measured before and after exercise.

Main Results:

  • Patients with MB showed a significant increase in QT dispersion (QTd) and corrected QT dispersion (QTcd) post-exercise.
  • QT maximum and minimum durations did not significantly change in MB patients after exercise.
  • Control group showed no significant changes in QT parameters after exercise.

Conclusions:

  • Treadmill exercise testing significantly increases QT dispersion in patients with myocardial bridging.
  • This observed increase in QT dispersion may stem from exercise-induced ischemia in the bridged artery territory.
  • Myocardial bridging warrants further investigation regarding its association with cardiovascular events.
Abstract

More Related Videos

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis18:11

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

Published on: December 28, 2012

Electrocardiogram Recordings in Anesthetized Mice using Lead II04:16

Electrocardiogram Recordings in Anesthetized Mice using Lead II

Published on: June 20, 2020

Related Concept Videos

Electrocardiogram01:29

Electrocardiogram

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 the T...
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...
Acute Coronary Syndrome III: Diagnostic Studies01:30

Acute Coronary Syndrome III: Diagnostic Studies

Diagnosing acute coronary syndrome or ACS begins with a thorough patient history. Notable symptoms include central, crushing chest pain radiating to the left arm, neck, jaw, or back, along with shortness of breath, sweating (diaphoresis), nausea, vomiting, dizziness, and palpitations.It is crucial to note any history of cardiac illnesses and assess risk factors, including age, gender, smoking, hypertension, diabetes, hyperlipidemia, and a sedentary lifestyle.During physical examination, vital...
Dysrhythmias IV: Characteristics of Bradyarrhythmias01:18

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 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...