Introduction Early repolarisation (ER) is commonly observed in athletes and young healthy individuals. Recently, ER in the inferior and lateral leads has been associated with sudden cardiac arrest from idiopathic ventricular fibrillation. We studied the prevalence, distribution and morphology of ER patterns in inferior and lateral leads in young healthy individuals.
Methods 12-leads ECG was performed at rest in 1237 young healthy individuals (age range 13–38 years) between February 2011 and September 2011. We evaluated the impact of gender, ethnicity and physical activity on ER. Individuals were divided into physically-active (exercise >2 h/week) and sedentary. Early repolarisation was defined as notched or slurred J-point elevation of at least 0.1 mV from baseline, in ¡Ý2 contiguous inferior or lateral leads; anterior ER patterns were not considered in this study. The morphology of ST-segment was classified as horizontal/descending or rapidly ascending/up sloping.
Results The mean age of participants was 18.2 ¡À 4.3 years, of which 979 (79%) were male, 981 (79%) were physically active and 91% were Caucasians. ER pattern was present in a total of 232 (18.7%) cases; of these 42% were in the inferior leads, 31% in lateral leads and 27% in both. Notched ER was more prevalent (64% inferior, 83% lateral, 76% infero-lateral) compared to slurred morphology, and more commonly associated with ascending/upsloping ST-segment elevation. ER was significantly more prevalent in males compared to females (20% vs 12%, p=0.003), in physically-active people compared to sedentary (20% vs 13%, p=0.0194), and in Afro-Caribbeans compared to Caucasians (40% vs 17%, p=0.0013). In addition, voltage criteria for left ventricular hypertrophy and sinus bradycardia were a common associated finding in individuals with ER pattern compared with those without (p=0.0001 and 0.002 respectively). Only 5% of individuals with ER had J-point elevation of >0.2 mV.
Conclusion Early repolarisation is a common finding in young healthy individuals, and is more prevalent in males, physically-active individuals and those with Afro-Caribbean ethnicity. Notched ER with ascending ST-segment elevation in inferior leads was the most commonly observed morphological pattern. More research is required to understand precise long-term implications of such repolarisation changes in young individuals.
- Early repolarisation
- pre-participation cardiovascular screening