Persistent juvenile T-wave pattern
Synonyms and keywords: Juvenile T waves

# Overview
The Juvenile T-wave pattern refers to a normal electrocardiographic variant in which T wave inversions are present in the right precordial leads (V1, V2, and V3) along with an early repolarization pattern. Shallow T-wave inversion is usually found in the right precordial leads during infancy, and T wave rises upwards during childhood. If this inverted T-wave pattern sustained to adulthood, it is called persistent juvenile T-wave pattern.

# Historical Perspective
The term Juvenile T-wave pattern was first introduced by American physician David Littman in 1946. 

# Natural History, Complications, Prognosis
Juvenile T-wave resolves completely in 98% of the patients, and those that persist into adulthood demonstrate no adverse sequela.

# Differentiating persistent Juvenile T-wave pattern from other causes of T-wave inversion
- Persistent juvenile T-wave inversion must be differentiated from other diseases that cause T-wave inversion, such as:
- Arrhythmogenic RV dysplasia should be suspected if the inverted T wave persists beyond lead V1 in a post pubertal male athlete.
- Cerebrovascular accidents can cause deep widely splayed T waves referred to as cerebral T waves.
- Digoxin effect or Dig effect typically shows the following findings:
- Sinus bradycardia
- T-wave inversions
- T-wave flattening
- U waves
- PR prolongation
- ST-segment depression with a scooped appearance
- Short QT due to an abbreviated ventricular action potential
- Hypokalemia can cause T-wave inversion, ST-segment depression, QT prolongation, and U wave.
- Ischemic heart disease including non ST-segment elevation myocardial infarction causes ST-segment depression and non-specific T wave changes.
- Left bundle branch block shows the following criteria on ECG:
- QRS duration is equal or greater than 120 milliseconds
- Absence of Q wave in leads I, V5 and V6
- Monomorphic R wave in I, V5 and V6
- T-wave deflection opposite to the major deflection of the QRS complex
- Left ventricular hypertrophy with strain is characterized by ST-segment depression and T-wave inversion.
- Myocarditis may cause sinus tachycardia, diffuse T-wave inversion, ST-segment elevation without reciprocal depression, and low voltage QRS complexes.
- Premature ventricular contraction is characterized by premature beats in relation to the expected beat, which leads to abnormal morphology and duration of QRS complexes.
- Pulmonary embolism may show inverted T wave in the anterior leads, particularly in massive pulmonary embolism.
- Restrictive cardiomyopathy may show low voltage QRS complexes and inverted T waves.
- Subarachnoid hemorrhage can cause ST-segment elevation and T-wave inversion.
- Unstable angina may show inverted T wave and ST-segment depression.
- Wellens' syndrome shows progressive symmetrical deep T-wave inversion in leads V2 and V3.
- Wolff-Parkinson-White syndrome (WPW) typically shows slurred upstroke of the QRS complexknown as delta waveand shortened P wave.

# Epidemiology and Demographics
- Juvenile T-wave pattern is more commonly seen in black peopleit has been shown in 10.8% of black population and 0.3% of white subjects.
- Juvenile T-wave pattern is more commonly found in females than males. 

# Diagnosis

## Electrocardiogram
Persistent juvenile T-wave pattern typically shows asymmetric T-wave inversion in V1-V3 without ST-segment elevation.

# Treatment
Persistent juvenile T-wave pattern can be normalized by the following medications: