Assessment of ventricular repolarization alterations in subjects with early repolarization Polychronis Dilaveris * , Antonios Pantazis, Elias Gialafos, John Gialafos, Pavlos Toutouzas, Christodoulos Stefanadis The University Department of Cardiology, Hippokration Hospital, Athens, Greece Received 3 March 2003; received in revised form 20 June 2003; accepted 25 July 2003 Abstract Background: Although the electrocardiographic (ECG) features of early repolarization (ER) have been studied extensively, no systematic quantification of ventricular repolarization in subjects with ER has been conducted so far. Methods: The objective of the present study was to evaluate ECG and spatial vectorcardiographic (VCG) descriptors of ventricular repolarization in ER subjects and to associate them with the respective indices of ventricular depolarization. A digital 12-lead surface ECG was obtained from 108 young, healthy men with ER and 108 age-matched healthy controls. The maximum Q-onset –T-end interval (QT maximum), the maximum Q-onset– T-peak interval (QTp maximum), the respective QT dispersion values (QT maximum – QT minimum), the rate-corrected QTC maximum and QTpC maximum, the QRS duration, and the VCG markers spatial T amplitude, spatial QRS amplitude and spatial QRS – T angle, were evaluated in ER subjects and controls. Results: QT maximum ( P = 0.05) and QTp maximum ( P = 0.003) were higher in ER subjects than in controls, while QTC maximum ( P < 0.0001) and QTpC maximum ( P = 0.002) were lower in ER subjects than in controls. The QRS duration ( P = 0.013), as well as the spatial T amplitude, the spatial QRS amplitude, and the spatial QRS – T angle were higher in ER subjects than in controls ( P < 0.0001). The spatial T amplitude was not associated with the indices of ventricular depolarization neither in ER subjects, nor in controls. Conclusions: Ventricular repolarization, as well as depolarization, is altered in young, healthy males with ER compared to age-matched healthy controls. Ventricular depolarization and repolarization indices in ER subjects are not associated to each other. D 2003 Elsevier Ireland Ltd. All rights reserved. Keywords: Early repolarization; Electrocardiogram; Vectorcardiogram 1. Introduction It is well known that electrocardiograms (ECGs) of apparently normal persons may show ST segment elevation mimicking cardiac disease. This form of ST segment eleva- tion was reported first by Shipley and Hallaran [1], then by Myers et al. [2] and Goldman [3], and commonly termed ‘‘early repolarization’’ (ER) [4]. This pattern occurs in approximately 1–2.5% of healthy adults [5] and is more commonly encountered in athletes, where its prevalence may vary from 10% in the general athletic population to 100% in selected groups of endurance-trained subjects [6]. While previous studies evaluated the morphological char- acteristics of this ECG variant [6–9] and its differences from diseases of abnormal ventricular repolarization [6], no systematic quantification of ventricular repolarization in subjects with ER has been conducted so far. The objective of the present study was to evaluate ECG and spatial vectorcardiographic (VCG) descriptors of ven- tricular repolarization in a population of young, healthy males with ER and to associate them with respective indices of ventricular depolarization. 2. Methods 2.1. Study population The study population was derived from 1394 servicemen of the Hellenic Air-Force who were consecutively recruited and had no history, clinical or resting ECG evidence of cardiovascular disease and were taking no cardioactive medications. Excluded from the study were patients with left or right bundle branch block, atrioventricular block, 0167-5273/$ - see front matter D 2003 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijcard.2003.07.020 * Corresponding author. 22 Miltiadou Street, 155 61 Holargos, Athens, Greece. Tel./fax: +30-1-6531-377. E-mail address: hrodil@yahoo.com (P. Dilaveris). www.elsevier.com/locate/ijcard International Journal of Cardiology 96 (2004) 273 – 279