Early repolarization syndrome is a genetic disorder of cardiomyocyte ion channel function (channelopathy). Patients are predisposed to polymorphic ventricular tachycardia (VT) and ventricular fibrillation (VF). Diagnosis is by ECG. Some patients require an implantable cardioverter defibrillator (ICD).
(See also Overview of Arrhythmias and Overview of Channelopathies.)
Early repolarization refers to ECG findings typically including J-point elevation ≥ 0.1 mV, often with a slurred or notched terminal QRS complex, followed by ST-segment elevation in ≥ 2 contiguous leads other than V1 to V3. This ECG pattern is not uncommon, as it occurs in about 5% to 10% of the population (1, 2, 3), especially in males, younger patients, and athletes. Most people with this early repolarization ECG pattern do not manifest arrhythmias. However, early repolarization is substantially more common in survivors of apparently idiopathic ventricular fibrillation (VF) (1, 2, 3). Early repolarization syndrome refers to people with early repolarization in inferior or lateral leads (predicting higher risk of arrhythmias) on ECG who also have had symptomatic ventricular arrhythmias (4).
Early repolarization syndrome appears to result from mutations that produce a
Gain of function of outward potassium current channels OR
Loss of function of inward sodium or calcium current channels
These ion channel changes magnify the normal small transmural voltage gradients during the plateau phase of the action potential. These gradients produce a J-wave and J-point elevation on the ECG and predispose to polymorphic ventricular tachycardia which can degenerate into ventricular fibrillation in the absence of other causes of early repolarization (eg, hyperthermia or hypothermia, hypocalcemia, hyperkalemia). The ECG changes are similar to those of the Brugada syndrome but appear in the inferior or lateral leads in the early repolarization syndrome rather than in the right precordial leads of the Brugada syndrome. This and other similarities has led to Brugada syndrome and early repolarization syndrome being grouped as J-wave syndromes (4). Prior to the VT/VF, the early repolarization pattern may become more exaggerated and the VT/VF may be precipitated by an episode of myocardial ischemia. -
Early repolarization syndrome appears to be inheritable, but disease-specific gene mutations are rarely identified, suggesting that the disorder is often polygenic.
The ventricular arrhythmias may cause palpitations and/or cardiac arrest. Syncope may occur but is uncommon because VT that occurs with early repolarization syndrome rarely self-terminates (unlike with some other disorders that cause VT in which syncope is more common).
General references
1. Haïssaguerre M, Derval N, Sacher F, et al: Sudden cardiac arrest associated with early repolarization. N Engl J Med 358(19):2016–2023, 2008. doi: 10.1056/NEJMoa071968
2. Rosso R, Kogan E, Belhassen B, et al: J-point elevation in survivors of primary ventricular fibrillation and matched control subjects: incidence and clinical significance. J Am Coll Cardiol 52(15):1231–1238, 2008. doi: 10.1016/j.jacc.2008.07.010
3. Tikkanen JT, Anttonen O, Junttila MJ, et al: Long-term outcome associated with early repolarization on electrocardiography. N Engl J Med 361(26):2529–2537, 2009. doi: 10.1056/NEJMoa0907589
4. Antzelevitch C, Yan GX, Ackerman MJ, et al: J-Wave syndromes expert consensus conference report: Emerging concepts and gaps in knowledge. Heart Rhythm 13(10):e295–324, 2016. doi: 10.1016/j.hrthm.2016.05.024
Diagnosis of Early Repolarization Syndrome
Characteristic clinical and ECG manifestations
Clinical screening of first-degree family members
Diagnosis should be considered in patients who have had polymorphic ventricular tachycardia, ventricular fibrillation, or sudden cardiac arrest (or a family history of those events) in the absence of structural heart disease and who also have ECG changes showing an inferior and/or lateral early repolarization pattern. The typical ECG finding of early repolarization is J-point elevation of ≥ 1 mm (≥ 0.1 mV) followed by ST segment elevation in ≥ 2 contiguous inferior and/or lateral leads. A probabilistic diagnosis scoring system (the Shanghai Early Repolarization Syndrome Score System) for the early repolarization syndrome has been proposed (1).
Because specific gene defects are seldom identified, genetic testing is not typically recommended for patients or family members. However, first-degree family members should be evaluated clinically and with an ECG.
Diagnosis reference
1. Antzelevitch C, Yan GX, Ackerman MJ, et al: J-Wave syndromes expert consensus conference report: Emerging concepts and gaps in knowledge. Heart Rhythm 13(10):e295–324, 2016. doi: 10.1016/j.hrthm.2016.05.024
Treatment of Early Repolarization Syndrome
Implantable cardioverter-defibrillator (ICD) if symptomatic
For patients who are asymptomaticbut have the early repolarization ECG pattern and no family history of sudden death, no treatment is recommended because such patients are at very low risk.
Patients who have had cardiac arrest or who have demonstrated VF or polymorphic VT are at high risk and have a class I indication for an ICD (1). An ICD may be considered for certain patients with the early repolarization ECG pattern and certain other high-risk features (2).
Treatment references
1. Al-Khatib SM, Stevenson WG, Ackerman MJ, et al: 2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Circulation 138(13):e272–e391, 2018. doi: 10.1161/CIR.0000000000000549
2. Priori SG, Wilde AA, Horie M, et al: HRS/EHRA/APHRS expert consensus statement on the diagnosis and management of patients with inherited primary arrhythmia syndromes: document endorsed by HRS, EHRA, and APHRS in May 2013 and by ACCF, AHA, PACES, and AEPC in June 2013. Heart Rhythm 10:1932–1963, 2013. doi: 10.1016/j.hrthm.2013.05.014
Key Points
Early repolarization syndrome is genetic and predisposes to polymorphic ventricular tachycardia (VT), ventricular fibrillation (VF), and sudden death.
Consider the diagnosis in patients who have had unexplained polymorphic ventricular tachycardia, ventricular fibrillation, or sudden cardiac arrest and early repolarization in the inferior or lateral leads on ECG.
Place an ICD in patients who have had cardiac arrest, ventricular fibrillation, or polymorphic ventricular tachycardia.
