Characterized by an elevation of the junction between the end of the QRS complex and the beginning of the ST segment (J point) from baseline on standard 12-lead electrocardiogram.
Characterized by concave upward ST segment elevation at the end of the QRS complex, most often in lateral and less commonly in the inferior and/or anterior per ordinal leads.
Considered an innocuous finding in most cases, but the presence of this pattern and leads other than V1 through V3 has been associated with vulnerability to ventricular fibrillation.
In a study of her early repolarization in a community based population of 10,864 middle-aged patients a pattern of early repolarization in the inferior leads was associated with increased risk of death from cardiac causes(Tikkanen JT).
In the above study early repolarization was stratified according to the degree J point elevation of 0.1 mV or greater than 0.0 0.2 mV: J point elevation of at least 0.1mV in the inferior leads was associated with increased risk of death from cardiac causes in those patients with a J-point elevation of more than 0.2mV in inferior leads had markedly elevated risk of death from cardiac causes.
The prevalence of J-point elevation of at least 0.1 mV in the inferior or lateral leads is 5.8% (Rosso R).
The early reploarization is associated with male gender and lower heart rates.
Early repolarization traditionally is viewed as a benign normal variant commonly seen in young individuals, especially male athletes.
It was generally held that early repolarization was generally harmless, if not even protective against future adverse cardiovascular events.
Among patients with J-point elevation QRS duration is longer, the QTc interval is shorter and the electrocardiographic signs of coronary artery disease are more prevalent than among individuals without this abnormality.
Early repolarization in inferior leads is a strong predictor of death from cardiac causes or from arrhythmias then J- point elevation in the lateral leads (Tikkanen JT).
J waves are present in inferior leads in many patients with idiopathic ventricular fibrillation(Rosso R).
How early repolarization in an inferior leads increases the risk from cardiac death is unclear.
J-ponit elevation is generally a stable phenomenon and is a marker of increased transmural heterogeneity of ventricular repolarization associated with increased vulnerability to ventricular tachyarrhythmias.
J-point elevation amplitude is associated with a higher risk of death from cardiac causes in patients with markedly elevated J point (>0.2 mV) compared to those with moderate elevation (0.1 mV).