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.

Background: Left bundle branch area pacing (LBBAP) offers physiological pacing with potential advantages over right ventricular (RV) pacing, particularly in children. However, data on LBBAP in pediatric populations are scarce. Objective: This study aimed to assess the feasibility and safety of LBBAP in children by reporting 6 cases done successfully. Methods: Six children (four males, two females), aged 2 to 16 years, underwent LBBAP between December 2022 and January 2024 at the American Univeristy of Beirut Medical Center (AUBMC). The implantation procedure followed established techniques. Baseline characteristics, echocardiographic measurements, and pacing parameters were recorded. Results: All six cases fulfilled the criteria for LBBAP. Successful LBBAP was achieved in all cases. Median weight is 20.5 kg, with three patients under 5 years old. Baseline left ventricular ejection fraction (LVEF) was normal in 4 cases, with two exhibiting 52%. The interventricular septal thickness averaged 4.5 mm. No major complications were encountered during follow-up. Conclusion: Left bundle branch area pacing might be a promising alternative to conventional RV pacing, offering potential advantages over traditional pacing methods. Further research is needed to fully elucidate its efficacy and long-term benefits in pediatric populations.

Background: Left ventricular (LV) pacing with resynchronization therapy improves ventricular synchrony in patients with decreased LV function and Left Bundle Branch Bock (LBBB). Objective: The goal of this study is to show that LV pacing is superior to BiVentricular (BiV) pacing in patients with ventricular dysfunction and LBBB. Methods: This is a retrospective study from 2 hospitals’ registries in Lebanon. 121 patients with LVEF ≤ 35%, a QRS ≥130msec and a LBBB pattern on full medical therapy were included in 2 groups: LV pacing and BiV pacing. All patients had echocardiograms before and after device implantation. The primary endpoint was the change in ejection fraction and the secondary endpoints were decrease in pulmonary artery pressure (PAPs), in LV end diastolic diameter (LVDD) and in LV end systolic diameter (LVSD). Statistical analysis was done with SPSS. Results: The study population was mostly males (69.4%) with ischemic cardiomyopathy 74 (61.2%) & a mean age of 67 years old. Fifty (41,3%) patients were programmed as LV pacing. A statistically significant improvement in EF was seen in the LV only 9.2% compared to BiV pacing 5.5%. Similarly, we noticed a significant decrease in the LVDD and LVSD in the LV pacing compared to the second group. There was a trend in favor of more PAPs improvement in the LV pacing that did not reach significance. Conclusion: This study demonstrates that LV pacing significantly improves EF and LV size compared to BiV pacing. A large multicenter trial is needed to confirm our findings.

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.