YAO Jing, XU Jing, YONG Yong-hong, CAO Ke-jiang, CHEN Shao-liang , XU Di

Background  Frequent premature ventricular complexes from the right ventricular outflow tract (RVOT-PVCs) are associated with left ventricular dysfunction. This study adopted two-dimensional speckle tracking imaging to evaluate global and regional left ventricular myocardial function in patients with frequent RVOT-PVCs.
Methods  This study included 30 patients with frequent RVOT-PVCs and 30 healthy subjects. Aortic systolic velocity-time integral (AoVTI) and myocardium strain in circumferential (CS), radial (RS) and longitudinal (LS) directions were evaluated by conventional echocardiography and speckle tracking imaging. All values of patients with RVOT-PVCs were recorded during sinus (PVC-S) and PVC beats (PVC-V).
Results  Significant differences were demonstrated in global CS, RS and LS between the control subjects and the PVC-V (CS: (17.46±2.48)% vs. (11.52±3.28)%, RS: (48.26±10.20)% vs. (20.92±9.78)%, LS: (19.89±2.62)% vs. (11.79±3.66)%, P <0.01), and in segmental RS and LS of nearly all the left ventricular segments. Statistical differences in segmental CS between the PVC-V and the control subjects were only observed in anterior, anteroseptal and septal segments (only seen in anteroseptal and septal segments at apex). Furthermore, V/S AoVTI (AoVTI during the PVC beat divided by AoVTI during the sinus beat, then multiplied by 100%) correlated with coupling interval (r=0.67, P <0.001) and global strain (CS: r=0.48, P=0.007; RS: r=0.65, P <0.001; LS: r=0.65, P <0.001).
Conclusions  Frequent RVOT-PVCs can induce global and regional left ventricular systolic dysfunction. The reduction of hemodynamic parameters relates to the coupling interval and the global systolic function.