Relationships between the T-peak to T-end interval, ventricular tachyarrhythmia, and death in left ventricular
Daniel P Morin1, Marc N Saad, Omar F Shams
1Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA. dmorin@ochsner.org
Aims:
The interval between the T-wave's peak and end (Tpe), an electrocardiographic (ECG) index of ventricular repolarization, has been proposed as an indicator of arrhythmic risk. We aimed to clarify the clinical usefulness of Tpe for risk stratification.
Methods And Results:
We evaluated 327 patients with left ventricular ejection fraction (LVEF) ≤ 35% (75% male, LVEF 23 ± 7%). All patients had an implanted implantable cardioverter-defibrillator (ICD). Clinical data and ECGs were analysed at baseline. Prospective follow-up for the endpoints of appropriate ICD therapy and mortality was conducted via periodic device interrogation, chart review, and the Social Security Death Index. During device clinic follow-up of 17 ± 12 months, 59 (18%) patients had appropriate ICD therapy, and during mortality follow-up of 30 ± 13 months, 67 (21%) patients died. A longer Tpe(c) predicted appropriate ICD therapy, death, and the combination of appropriate ICD therapy or death (P< 0.01 for each endpoint). On multivariable analysis correcting for other univariable predictors, Tpe(c) remained predictive of ICD therapy [hazard ratio (HR) per 10 ms increase: 1.16, P= 0.02], all-cause mortality (HR per 10 ms: 1.14, P= 0.03), and the composite endpoint of ICD therapy or death (HR per 10 ms: 1.16, P< 0.01).
Conclusions:
In patients with left ventricular systolic dysfunction and an implanted ICD, Tpe(c) independently predicts both ventricular tachyarrhythmia and overall mortality.
Related Concept Videos
01:28Dysrhythmias II: Classification of Tachyarrhythmias
01:25Correlation between ECG and 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...
01:28Electrocardiogram Fundamentals
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 to...
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
01:29Disturbances in Heart Rhythm
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
01:29Dysrhythmias III: Characteristics of Dysrhythmias