Radiofrequency Catheter Ablation of Left Accessory Pathways Using Conventional Methods

Abstract Radiofrequency catheter ablation of accessory pathways is considered the treatment of choice for patients with atrioventricular reentry tachycardia due to its proven safety and effectiveness. The aim of this study was to compare the outcomes of this treatment for left-sided accessory pathways in 58 consecutive patients with manifest preexcitation who were treated at the Institute for Cardiovascular Diseases Dedinje. The procedure duration varied significantly (p<0.05) depending on the localization of accessory pathways along the mitral annulus (anterior 60.0±26.0 min; anterolateral 45.2±28.4 min; lateral 73.9±27.9 min; posterolateral 59.1±25.5 min; posterior 83.1±29.6 min), as did the number of applied radiofrequency pulses (anterior 9.0±4.5; anterolateral 4.3±4.7; lateral 8.1±5.8; posterolateral 4.0±2.9; posterior 8.1±4.2; p<0.05). Fluoroscopy exposure time did not differ significantly (p=0.078). Atrial fibrillation was recorded in 15.5% of patients prior to the procedure. For the ablation of left-sided accessory pathways, the transaortic approach was used significantly more often (74.1%) than the transseptal approach. There were no significant differences among the groups in terms of primary procedural success (100% for anterior and anterolateral, 82.1% for lateral, 100% for posterolateral, and 88.9% for posterior; p=0.672), recurrence rate (10.7% for lateral and 5.5% for posterior; p=0.023), or final success rate, defined as definitive cure (100% for anterior, anterolateral, and posterolateral, 94.8% for lateral, and 89.3% for posterior; p=0.421). Despite the increased time and more radiofrequency energy pulses necessary for ablating laterally and posteriorly positioned accessory pathways, the procedure's success rate remained comparable regardless of accessory pathways location along the mitral annulus.