As mentioned in the previous section, early repolarization is known as appearing as elevated wave segments on ECGs. Recent studies have shown a connection between early repolarization and sudden cardiac death, which is identified as early repolarization syndrome. The condition is shown in both ventricular fibrillation without other structural heart defects as well as an early depolarization pattern, which can be seen on ECG.
The primary root of early repolarization syndrome stems from malfunctions of electrical conductance in ion channels, which may be due to genetic factors. Malfunctions of the syndrome include fluctuating sodium, potassium, and calcium currents. Changes in these currents may result in overlap of myocardial regions undergoing different phases of the action potential simultaneously, leading to risk of ventricular fibrillation and arrhythmias.
Upon being diagnosed, most individuals do not need immediate intervention, as early repolarization on an ECG does not indicate any life-threatening medical emergency. Three to thirteen percent of healthy individuals have been observed to have early repolarization on an ECG. However, patients who display early repolarization after surviving an event of early repolarization syndrome (a sudden-cardiac death experience), an implantable cardioverter-defibrillator (ICD) is strongly recommended. In addition, a patient may be more prone to atrial fibrillation if the individual has early repolarization syndrome and is under sixty years of age.