Related Experiment Video
Updated: Jun 21, 2026
04:45
Real-Time Electrocardiogram Monitoring During Treadmill Training in Mice
Published on: May 5, 2022
T-wave variability detects abnormalities in ventricular repolarization: a prospective study comparing healthy persons
Lara Heinz1, Anik Sax, Francois Robert
1Department of Medicine-Cardiology, University of Bonn, Bonn, Germany.
Summary
A new heart rhythm measure, T-wave variability (TVar), detected significant differences in athletes compared to controls. This may indicate early changes in ventricular repolarization, potentially signaling risk for life-threatening arrhythmias.
Area of Science:
- Cardiology
- Sports Medicine
- Electrophysiology
Background:
- Sudden cardiac death (SCD) is more prevalent in athletes than the general population.
- Routine screenings aim to identify athletes at risk for SCD.
- Ventricular repolarization variation (TVar) is a novel Holter-based parameter for risk assessment.
Purpose of the Study:
- To evaluate differences in electrocardiogram (ECG), echocardiogram (Echo), and Holter (H) parameters between competitive athletes and healthy medical students (MS).
- To assess the utility of TVar in differentiating athletes from a control group.
Main Methods:
- 40 competitive athletes and 40 MS underwent resting ECG, treadmill exercise (TE), Echo, and 20-minute resting Holter (H) recordings.
- T-wave variability (TVar), heart rate variability (HRV), and heart rate turbulence (HRT) were computed.
- Echocardiography assessed cardiac structure, including septal and posterior wall thickness.
Main Results:
- Athletes showed increased vagal modulation of autonomic cardiac function compared to MS.
- Echocardiography revealed a thicker septal wall in athletes, but no difference in posterior wall thickness.
- TVar values differed significantly between athletes and MS, despite being within normal ranges, with no correlation to Echo or other Holter parameters.
Conclusions:
- TVar effectively identified significant differences in ventricular activation patterns between athletes and controls.
- These TVar differences may represent early myocardial repolarization alterations, potentially predisposing to arrhythmias.
- Larger studies with follow-up are needed to establish the predictive value of TVar for life-threatening arrhythmias in athletes.
Related Concept Videos
01:29Electrocardiogram
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...
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...
01:25Correlation between ECG and Cardiac Cycle
The electrical signals recorded on an electrocardiogram (ECG) occur before the mechanical processes of contraction and relaxation during the cardiac cycle.
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
01:30Dysrhythmias V: Evaluating Dysrhythmias
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...
01:19Electrophysiology of Normal Cardiac Rhythm
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 of...
01:28Dysrhythmias 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...
01:30Acute 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...