Overview
Left atrioventricular (AV) valve leaflet abnormalities can manifest as accessory AV connections, affecting normal cardiac conduction and potentially leading to preexcitation syndromes like Wolff-Parkinson-White (WPW) syndrome. These abnormalities involve additional pathways that bypass the normal AV node, impacting the timing and sequence of ventricular activation.Diagnosis
Electrocardiographic (ECG) findings: Presence of delta waves and short PR intervals indicative of ventricular preexcitation 2.
Electrophysiologic studies: Mapping and local electrogram analysis to identify accessory pathways and assess successful ablation sites 1.
Ventricular preexcitation patterns: Local ventricular electrograms can differentiate between successful and unsuccessful ablation sites, with PQS patterns correlating with higher success rates 1.Management
Radiofrequency catheter ablation: Primary treatment for symptomatic accessory AV connections, targeting successful sites characterized by continuous electric activity and shorter time intervals 1.
Electrogram pattern assessment: Utilize PQS pattern in unipolar electrograms for predicting successful ablation sites 1.Special Populations
No specific guidance provided: Abstracts do not cover pregnancy, pediatrics, elderly, or comorbidities directly related to left AV valve leaflet abnormalities 12.Key Recommendations
Perform radiofrequency catheter ablation targeting sites with continuous electric activity and shorter measured time intervals for higher success rates (Evidence: Moderate) 1.
Utilize PQS pattern in unipolar electrograms to identify optimal ablation sites (Evidence: Moderate) 1.
Consider electrophysiologic studies for detailed mapping and assessment of accessory pathways in patients with suspected accessory AV connections (Evidence: Moderate) 12.References
1 Grimm W, Miller J, Josephson ME. Successful and unsuccessful sites of radiofrequency catheter ablation of accessory atrioventricular connections. American heart journal 1994. link90013-2)
2 Mitchell LB, Mason JW, Scheinman MM, Winkle RA, Burchell HB. Recordings of basal ventricular preexcitation from electrode catheters in patients with accessory atrioventricular connections. Circulation 1984. link