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Objective:To investigate the effect of instantaneous flow rate on the consistency of diagnostic accuracy of severe degenerative mitral regurgitation (DMR) using proximal isovelocity surface area (PISA).Methods:From June 2019 to June 2021, 75 patients with DMR who underwent echocardiography in Department of Echocardiography of Zhongshan Hospital, Fudan University were prospectively enrolled. The instantaneous flow rate of DMR during the systolic phase was calculated using M-mode PISA(PISA M-mode), and a time-integrated curve was plotted. Regurgitant volume (RVol) and effective regurgitant orifice area (EROA) were calculated by traditional PISA (PISA max), pair PISA (PISA pair), and PISA M-mode, respectively. RVol acquired from cardiac magnetic resonance (CMR) volumetric method in 22 patients of the enrolled patients. The correlation and consistency of RVol acquired between the three PISA methods and CMR were compared. Agreement of diagnostic accuracy of severe mitral regurgitation (sMR) acquired between the three PISA methods and multi-parameter algorithm by American Society of Echocardiography (ASE) was analyzed using Cohen′s Kappa analysis. Results:The curve of instantaneous flow rate of DMR showed unimodal pattern with the peak at mid-late systolic phase. The correlation of RVol acquired between PISA methods and CMR was moderate for PISA max and PISA pair ( r=0.77, 0.80, both P<0.001), whereas PISA M-mode presented strong correlation with CMR ( r=0.87, P<0.001). RVol acquired from PISA max was larger than that of CMR[(69.1±37.1) ml vs (49.0±29.0)ml, P=0.002]. Both PISA max and PISA pair were shown moderate agreement of diagnostic accuracy of sMR with ASE multi-parameters algorithm (RVol: κ=0.496, 0.525, both P<0.001; EROA: κ=0.570, 0.578, both P<0.001), while PISA M-mode presented strong agreement (RVol: κ=0.867 and EROA: κ=0.802, both P<0.001). Conclusions:Based on the unimodal pattern of instantaneous flow rate in patients with DMR, PISA max may significantly overestimate RVol, exposing a significant proportion of patients with DMR to unnecessary MR surgery. PISA M-mode presents better correlation and consistency with CMR on the quantification of RVol compared with PISA max and PISA pair, and may improve the diagnostic accuracy of quantification of sMR using PISA.
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Objective To assess left ventricular (LV) twist in a rapid pacing induced heart failure canine model undergoing cardiac resynchronization therapy (CRT) by three-dimensional speckle tracking imaging (3D-STI).Methods Rapid right ventricular pacing (RVP) was utilized in 22 adult beagle dogs for 3 weeks to induce heart failure.Then 15 dogs received CRT for 2 weeks and others were treated as control.Apical full-volume acquisition of the LV was obtained in conscious animals at baseline,the end of 3-week RVP and the end of 2-week CRT.Peak LV apical (AP-Prot) and basal rotation (MV-Prot) along with peak twist (Ptw) and torsion (Ptor) were automatically calculated by TomTec 4D LV Analysis 3.0 software to identify the ideal parameter in predicting treatment response of CRT.Results After 2 weeks of CRT,LV ejection fraction(LVEF) increased and LV end-systolic volume(LVESV) decreased significantly in dogs with heart failure.CRT treatment response,defined as improvement of LVESV≥15％,was observed in 9 dogs.Significant difference was found in Ptw [(7.43 ± 0.61) vs (6.06 ± 0.89)°,P ＜0.05] and Ptor [(1.43 ± 0.45) vs (0.67 ± 0.36)°/cm,P ＜0.05] between responders and nonresponders.Ptw and Ptor predicted CRT response with satisfying sensitivity as 89％ and 85％,specificity as 83％ and 84％,respectively.Conclusions Peak twist and torsion evaluated by 3D-STI represented overall LV twist and demonstrated potential prediction value for treatment response of CRT.
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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 duration:pQRSd 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.
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Objective To investigate new parameters to predict the response to cardiac resynchronization therapy (CRT) by using real-time three-dimensional echocardiography (RT3DE) and speckle tracking imaging(STI). Methods Twenty-one adult beagle dogs were divided into three groups:group A (CRT group, n =10) ,group B (heart failure group, n =7) and group C (control group, n =4).Seventy patients who accepted CRT and were followed up 6 months after CRT were enrolled. Response to CRT was defined as a ≥15％ decrease in left ventricular end-systolic volume. RT-3DE parameters were the dispersion of time to minimum regional volume for 16 segments (Tmsv16-SD) ,and the ratio of Tmsv16-SD to R-R interval (SDI). STI parameters were the ratios of standard deviation of the time to peak radial and circumferential strain at midventricular level to R-R interval (Trs-6SD,Tcs-6SD). Results In experimental study,Tmsv-16SD, Trs-6SD, Tcs-6SD had negative relationship with left veutricular ejection fraction (r were - 0. 86, - 0.75, - 0.83 respectively, all P ＜0.01 ). Trs-6SD was the strongest predictor to CRT. A cut-off value of Trs-6SD≥12.2％ was able to predict response to CRT with a sensitivity of 83.3％ and a specificity of 100％. Clinical studies found SDI was the strongest predictor to CRT. A cut-off value of SDI≥6.55％ was able to predict response to CRT with a sensitivity of 80. 0％ and a specificity of 81.8％.Conclusions RT-3DE and STI can assess left ventricular dyssynchrony, and are promising methods to predict the response to CRT.
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The endotoxemia model was established by intraabdominal injection of endotoxin Coli B. (E. Coli O55B5,8 mg/kg weight)in albino rats. Two hours before administration of endotoxin, the ejiao recovery-pulse decoction was perfused into the stomach tube of the rats in the experimental group (10mg/kg weight), and 12h later, the platelets were counted, kaolin activated partial thromboplastin time (KPTT), prothrombin time (PT) and thrombin time (TT) were measured, and malondialdehyed (MDA) levels in plasma and platelet were determined by thiobarituric acid (TBA) fluorometry. The results demonstrate that the ejiao recovery-pulse decoction could prevent from peripheral platelet dropping, KPTT and TT prolonging and MDA level rising which were caused by endotoxin.