A Tug of War

Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads.1,2 The J point deflection occurring at the QRS-ST junction (also known as Osborn wave or J wave) was first described in 1938, and is seen in both extracardiac and cardiac disorders like hypothermia, hypercalcemia, brain injury, hypervagotonia, or spinal cord injury leading to loss of sympathetic tone, vasospastic angina. Besides recently described early repolarization syndrome,3–5 ERP has generally been considered a normal ECG variant with good long-term prognosis. However, this long-held concept has been challenged, and recently published population-based studies and reports of associations with ventricular fibrillation and sudden death continue to fuel more momentum.6–9 In the seminal article by Haïssaguerre et al, cases of ERP associated with cardiac arrest had at least 0.1-mV J point elevation manifested as QRS slurring or notching in the 2 contiguous inferior or lateral leads.6 ERP has also emerged as a marker of increased long-term mortality (cardiac and arrhythmic) in the general population.10,11 Thus, ERP is probably not as benign as traditionally believed.