Examination of pathological features of the right atrioventricular groove in hearts with Ebstein’s anomaly, and correlation with arrhythmias.
Heart Rhythm. 2020 Jan 21;:
Authors: Marcondes L, Sanders SP, Del Nido PJ, Walsh EP
BACKGROUND: Catheter ablation of accessory pathways (AP) in Ebstein’s anomaly (EA) has a higher recurrence rate than in normal hearts. Anatomic features could account for suboptimal ablation outcomes.
OBJECTIVES: Examine right atrioventricular (AV) groove in autopsy hearts with EA, correlate with clinical data, and identify features relevant for catheter ablation.
METHODS: Thirty three specimens with EA were examined from our Cardiac Registry. The right AV groove was inspected for gross anatomic features. Limited microscopy was performed on selected specimens. Pre-mortem clinical data were correlated with anatomical findings.
RESULTS: A prominent ridge along the right AV groove was seen in 15/33 specimens (45%). Ten specimens had a clinical history of AP (AP+). The extent of ventricular atrialization did not differ between AP+ and AP- groups (64 ± 63mm/m2 vs 76 ± 42mm/m2, p=0.61), nor did the presence of visible macroscopic AV tissue connections (45% vs 51%, p=0.68). The single item that differed was the presence of an AV groove ridge itself, which was significantly more common in the AP+ group (70% vs 21%, p=0.03). Microscopy of ridge tissue revealed a muscular bundle in one AP+ specimen penetrating deep into the fibrous AV annulus that was suggestive of an AP, although complete muscular continuity was not verified in the limited sections available for examination.
CONCLUSIONS: A prominent ridge along the inferior right AV groove is a common feature in EA, and correlates with clinical history of AP. It presents a potential obstacle to catheter ablation, and may contribute to recurrence rate.
PMID: 31978592 [PubMed – as supplied by publisher]