ORIGINAL ARTICLE Dispersion Durations of P-wave and QT Interval in Children With Congenital Heart Disease and Pulmonary Arterial Hypertension Fatih S ¸ ap • Zehra Karatas ¸ • Hakan Altin • Hayrullah Alp • Bu ¨ lent Oran • Tamer Baysal • Sevim Karaarslan Received: 10 June 2012 / Accepted: 26 August 2012 / Published online: 13 September 2012 Ó Springer Science+Business Media, LLC 2012 Abstract This study aimed to investigate homogeneity disorders of ventricular repolarization and atrial conduction via QT dispersion and P-wave dispersion in children with congenital heart disease (CHD) and pulmonary arterial hypertension (PAH). Three groups of 20 each were gen- erated and involved in this study. The first group included 20 children with both CHD and PAH. The second group consisted of 20 children with CHD but no PAH, and the third group was composed of 20 age- and sex-matched healthy children. Electrocardiographic records were used to determine P-wave, QT, and corrected QT (QTc) disper- sions. The pulmonary hypertension group compared with the group having no pulmonary hypertension and the control group showed a significantly longer P-wave dis- persion duration (39.10 ± 9.54 vs. 26.30 ± 4.99 ms, p \ 0.001; and 24.80 ± 6.94 ms, p \ 0.001, respectively) and QT dispersion duration (52.80 ± 15.11 vs. 37.60 ± 6.00 ms, p \ 0.001; and 35.00 ± 7.77 ms, p \ 0.001, respectively). In addition, the durations of maximum QTc and QTc dispersion were significantly longer in pulmonary hypertension group than in the other two groups. The risk of atrial and ventricular arrhythmia was found to be increased in the patients with both CHD and PAH. Physicians should pay close attention to possible atrial and ventricular arrhythmias during the treatment and follow-up evaluation of these patients. Keywords Cardiac defects Á Childhood Á Electrocardiographic markers Á Pressure of pulmonary vasculature Introduction Pulmonary arterial hypertension (PAH) is rarely seen during childhood. Although it can develop due to a variety of causes, 90 % of the cases are either composed of idio- pathic diseases or occur secondary to congenital heart diseases (CHDs) with left-to-right shunting [6]. Elevation of pulmonary artery pressure and the anatomic condition of pulmonary vascular structures are important determinants in the clinical manifestation of the disease and in deter- mining the prognosis [12]. Pulmonary arterial hypertension is defined as a mean pulmonary artery pressure of 25 mmHg or higher, mea- sured at right heart catheterization in a resting person [10]. It is known that PAH increases the tendency for a variety of arrhythmias to develop [1, 18, 21]. Therefore, the origi- nation of an impulse from the sinus node and the distri- bution and progression of this impulse in the atrium and the ventricle can be easily shown with noninvasive surface 12-lead electrocardiography (ECG). Additionally, on a 12-lead ECG, maximum P-wave and P-wave dispersion (PWD) durations are used to determine whether the sinus impulse is distributed homogeneously. These two measures also are used to determine the intra- and interatrial conduction times. Although findings have shown the P-wave duration to be important in a variety of F. S ¸ap (&) Department of Pediatric Cardiology, Konya Training and Research Hospital, Meram Yeniyol Street, Number: 97 Meram, Konya, Turkey e-mail: fatihsap@gmail.com Z. Karatas ¸ Á H. Altin Á H. Alp Á T. Baysal Á S. Karaarslan Meram Medical Faculty, Department of Pediatric Cardiology, Necmettin Erbakan University, Konya, Turkey B. Oran Selcuklu Medical Faculty, Department of Pediatric Cardiology, Selcuk University, Konya, Turkey 123 Pediatr Cardiol (2013) 34:591–596 DOI 10.1007/s00246-012-0503-5