The present study is the second report on the safety and efficacy of catheter ablation of supraventricualr tachyarrhythmias (SVT) based on retrospective results and it is the second registry to be done in Egypt (Cairo University) on SVT ablation. It is also unique because of its relatively significant number, the inclusion of data from children and adult, and it involves the results of RF ablation of AVNRT, AVRT, atrial tachycardia (AT), atrial flutter (AFL), and SNRT. The present study reflects the growing experience of the Critical Care department, Cairo University hospitals for ten years in ablating different types of SVT. The results of the present study indicates that catheter ablation could be done with a high success rate and low incidence of complications. In this study, the success rate was 82.5%, the recurrence rate and the incidence of complication were low (4.5%, and 8.7% respectively). Only 3% experienced major complications with no mortality. The study also identified some types of SVT that were jointly predictive of ablation success as AVNRT (90%), anteroseptal AP (96.1%), left posterolateral AP (92.3%) and left lateral AP (90.8%). It also identified some types of SVT that were jointly predictive of ablation failure as atrial tachycardia with failure rate (30%), atrial flutter (20%), left posteroseptal AP (30.7%), and right lateral AP (22.3%). It also identified the clinical variables that jointly predicted development of complications as structural heart disease, multiple ablation targets, AVNRT, and anteroseptal AP. The 4 clinical variables that jointly predicted an increased risk of arrhythmia recurrence were Mahaim fibers tachycardia, atrial flutter, multiple APs, and posteroseptal APs.