Three-dimensional speckle tracking imaging permits qualification of left ventricular twist in dogs with heart failure / 中华超声影像学杂志

ABSTRACT

ObjectiveTo assess left ventricular (LV) twist in Beagle dogs with rapid-pacing induced heart failure by 3-dimensional speckle tracking imaging.MethodsSeventeen adult beagle dogs underwent rapid right ventricular pacing (RVP) to induce heart failure.Right ventricles were paced at 260 beats/min for 3 weeks.Apical full-volume acquisition of the LV was obtained in conscious animals at baseline and the end of 3-week rapid pacing.Peak LV apical rotation(AP-Prot) and basal rotation (MV-Prot) accompanied with peak twist (Ptw) and torsion were automatically calculated by TomTec 4D LV Analysis 3.0 software.The relation between LV twist and QRS duration was further studied.Results After 3 weeks of rapid ventricular pacing,AP-Prot,MV-Prot,Ptw decreased significantly [At-Prot(13.96 ± 2.00) ° vs (5.85 ± 0.58)°；MV-Prot(3.34± 0.38)° vs (2.13 ± 0.44)°； Ptw(16.31 ± 2.01)° vs (7.08 ± 1.16)°,all P ＜0.05].Dogs with heart failure were divided into two groups according to the QRS durationpQRSd group with QRS≥100 ms and nQRSd group with QRS＜100 ms.No significant difference was found in AP-Prot and MV-Prot between two groups ( P ＞0.05).In the pQRSd group,the peak of apical rotation occurred earlier than the peak of basal rotation [(162.89 ± 14.33) ms vs (91.43 ± 15.45) ms,P ＜0.05],which might resulted in further worsening of peak LV twist [pQRSd(6.02 ± 0.74)° vs nQRSd(7.91 ± 0.53)°,P ＜0.05].Conclusions LV twist dynamics was a good indicator of LV systolic function and had the potential to evaluate LV systolic dyssynchrony.