Introduction: The aim of this study was to describe our experience and outcome of ablation therapy of arrhythmias in children at a tertiary care center. Methods: Data was collected retrospectively from the hospital medical records. All children presenting to AUBMC between 2000 and 2020 who underwent cardiac ablation were included. The data collected included type of arrhythmia, ablation technique, age and weight at ablation, procedure complications, medications used, and outcome assessment. Results: We had 67 patients who underwent cardiac ablation. Of those, 60% were males with a mean age of 15 years. Structural heart disease was present in 6% of patients. Wolff-Parkinson-White syndrome (WPW) was most prevalent at 31%, followed by atrioventricular nodal reentrant tachycardia (AVNRT) at 24%, atrioventricular reentrant tachycardia (AVRT) at 19%, ventricular tachycardia (VT) at 10%, atrial fibrillation (AF) at 2%, and atrial tachycardia (AT) at 1%. The remaining 13% of patients presented with less common types of arrhythmias, including narrow complex tachycardia, retrograde dual atrioventricular nodal reentry, premature ventricular contractions (PVC), and orthodromic reciprocating tachycardia. Antiarrhythmic medications were started prior to the procedure in 59% of our population. Medication regimens post-ablation included beta blockers (68%), type 1c antiarrhythmics (25%), calcium channel blockers (3%), ivabradine (2%), and amiodarone (2%). The completed procedures showed a success rate of 93%. Conclusion: Ablation of arrhythmias in children is an effective procedure in the treatment of childhood arrhythmias. More studies are needed on cardiac ablation in children with structural heart disease in the Middle East region.

Introduction: QT interval represents the ventricular depolarization and repolarization. Its accurate measurement is critical since prolonged QT can lead to sudden cardiac death. QT is affected by heart rate and is corrected to QTc via several formulae. QTc is commonly calculated on the ECG and not the 24-hour Holter. Methods: 100 patients presenting to our institution were evaluated by an ECG followed by a 24-hour Holter. QTc measurement on both of these platforms using Bazett and Fridreicia formulae was recorded and compared. Results: Mean age was 14.09 years, with the majority being males. Mean heart rate was 125.87. In the ECG, the mean QTc interval via Bazett formula was 0.40 seconds compared to 0.38 seconds using the Fridreicia formula. The mean corrected QT via Bazett formula was 0.45, 0.39 and 0.42 seconds for the shortest RR, longest RR and the average RR respectively. In contrast to Fridreicia formula, the corrected QT interval was 0.40, 0.39, and 0.40 seconds for the shortest RR, longest RR and the average RR respectively. Using Bazett, highest specificity reached during longest RR interval (92.2%) while highest sensitivity was recorded during shortest RR interval (40%). As for Fridreicia, sensitivity always reached 0% while highest specificity was reached during average RR interval. Conclusion: QTc measured during Holter ECG reached a high specificity regardless of RR interval using the Fridreicia and during long and average RR interval for Bazett formula. The consistently low sensitivity reveals that Holter ECG should not be used to rule out prolonged QT.