Radiofrequency Ablation Blocked Bypass The Pre-shock Syndrome In Patients With Left Ventricular Contraction Synchrony

Objective The purpose of this study was to observe the influence of radiofrequency current ablation( RFCA)on left ventricular (LV) systolic synchrony in patients with Wolff-Parkinson-White (WPW) syndrome by phase analysis of gated SPECT myocardial perfusion imaging (GSPECT MPI). Methods 44 WPW patients were enrolled, and 35 had phase analysis of GSPECT MPI pre and 2-3 days post RFCA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Phase analysis was used to analyze the GSPECT MPI data to assess LV systolic synchrony pre and post RFCA. Results Baseline LV systolic dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p<0.05). RFCA improved LV systolic synchrony in the entire cohort and in the patients with septal APs (p<0.01). Conclusion Phase analysis demonstrated that LV systolic dyssynchrony is present in patients with WPW, especially in those with septal APs, and that RFCA can improve LV systolic synchrony in patients with WPW. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis. Objective The purpose of this study was to observe the influence of RFCA on LV systolic synchrony in patients with WPW syndrome by quatitative tissue velocity imaging(QTVI). Methods The study group consisted of 17 patients with WPW syndrome and recurrent episodes of atrioventricular tachycardia without any concomitant diseases. QTVI was performed in these 17 patients pre and 1-2 days post RFCA. The regional velocity profiles of the different segments of LV along LV apical longaxis view,apical two-chamber view and four-chamber view were obtained. The time from onset of QRS complexes to peak velocity during systole(Ts)were measured.The standard deviation of Ts (Ts-12-SD)were computed and Ts-12-SD>33ms was defined as the index of LV systolic dyssynchrony. According to Ts-12-SD>33ms,the patients were categorized into two groups (the subgroup with baseline LV dyssynchrony, the subgroup without baseline LV dyssynchrony) before RFCA. Results Delta waves were absent in all 17 patients after RFCA. Significant reduction in QRS duration and whole QRS area post RFCA was observed in the entire population as well as in the subgroups(P< 0.05). The percentage of patients with LV systolic dyssynchrony in all 17 patients was 58.8%(10/17), when Ts-12-SD>33ms was defined as the index of LV systolic dyssynchrony. Significant improvement in LV systolic synchrony post RFCA was observed in the entire cohort as well as in the subgroup with baseline LV systolic dyssynchrony(P< 0.05). There was no statistical differences comparing Ts-12-SD before and after RFCA in the subgroup without baseline LV systolic dyssynchrony(P>0.05).Conclusion RFCA can improve LV systolic synchrony in patients with WPW syndrome.