Two-dimensional speckle-tracking echocardiography for atrioventricular accessory pathways persistent ventricular pre-excitation despite successful radiofrequency ablation

Abstract

Aims: The present study was undertaken to investigate the concordance between longitudinal two-dimensional (2D)-speckle-tracking data and endocardial mapping for localizing atrioventricular accessory pathways (AP), and whether longitudinal 2D-speckle-tracking imaging accurately identifies the contractile abnormalities associated with AP and the effect of radiofrequency ablation.

Methods and results: Echocardiograms were repeated twice in 40 patients with Wolff-Parkinson-White (WPW) syndrome (before and early after ablation) and in 40 healthy controls to obtain longitudinal 2D strain and strain rate data. The site of ablation was considered as the gold standard for the AP localization. While control patients had a homogeneous strain pattern, all but two patients with WPW had an abnormal deformation pattern with three peaks in one or two basal contiguous segments: an early peak concomitantly with the delta wave followed by a systolic and a post-sytolic one. The rapid increase in LV longitudinal deformation within the basal pre-excited zone resulted in a pre-systolic peak strain rate at the beginning of the delta wave by SR imaging that was not found in controls. The early basal contraction spread towards the mid-ventricle before merging with the normal activated segments in 15 patients (39%). Contractile abnormalities were no more than one adjacent segment different compared with the AP ablation site in all these 38 patients. Regional strain was impaired in the pre-excited areas especially in AP localized in the interventricular septum. The abnormal deformation pattern persisted in 16 (42%) patients despite successful radiofrequency ablation. However, the difference in the regional strain between WPW patients and controls did not remain after ablation.

Conclusion: Longitudinal 2D-speckle-tracking data accurately match with endocardial mapping findings for localizing AP. Longitudinal 2D-speckle-tracking imaging accurately identifies AP-associated contractile abnormalities. Longitudinal 2D-speckle-tracking identifies persistence of local ventricular pre-excitation immediately after successful ablation.