Session II: Invasive Diagnosis and Treatment-6154-Physiology, Mapping and Catheter Ablation of Accessory Pathways

Video Transcription

Video Summary

In this video, Professor Bill Miles discusses various types of accessory pathways and their ablation. The most common type of accessory pathway is periannular AV connections, which can conduct bidirectionally or retrogradely or anterogradely only. Other types of pathways include atrial fascicular pathways, fasciculoventricular connections, notofascicular or notoventricular connections, and appendage ventricular connections. The indications for accessory pathway ablation are pathways involved in supraventricular tachycardia with short refractory periods, but not located in high-risk areas. However, it is unnecessary to ablate an accessory pathway with poor anterograde conduction in an asymptomatic patient without spontaneous or inducible SVT. Different types of accessory pathways may manifest as multiple delta wave morphologies in atrial fibrillation or exhibit different AV block cycle lengths. Electrocardiogram localization can help identify the location of accessory pathways by observing delta wave orientation and P wave morphology during tachycardia. Intracardiac mapping can be performed using anagrade or retrograde techniques to determine the location of the accessory pathway insertion site. Catheter stability is crucial during ablation, and different ablation characteristics indicate successful ablation sites, such as stable electrograms with both atrial and ventricular components and a decrease in impedance during energy delivery. Certain precautions need to be taken when ablations are performed near the AV node to avoid AV block. Other accessory pathway variants discussed in the video include atriofascicular pathways, permanent junctional reciprocating tachycardia, nodofascicular pathways, and fasciculoventricular pathways. Overall, accessory pathway ablation is highly successful with few major complications.

Keywords

accessory pathways

ablation

periannular AV connections

atrial fascicular pathways

fasciculoventricular connections

delta wave morphologies

intracardiac mapping

catheter stability

complications