瞬时流量动态变化对定量退行性二尖瓣反流严重程度的影响

Effect of dynamics of instantaneous flow rate on the quantification of the severity of degenerative mitral regurgitation using M-mode proximal isovelocity surface area

目的探索瞬时流量动态变化对近端等速表面积法(PISA)定量退行性二尖瓣反流(DMR)严重程度准确性的影响。方法前瞻性纳入2019年6月至2021年6月于复旦大学附属中山医院心超室行超声心动图检查的DMR患者75例。通过M型PISA法(PISA M-mode)计算并绘制瞬时流量变化曲线。分别采用传统PISA法(PISA max)、匹配PISA法(PISA pair)和PISA M-mode计算75例DMR患者的反流容积(RVol)和有效反流口面积(EROA),采用容积法计算其中22例接受心脏磁共振(CMR)检查的DMR患者的RVol。比较三种PISA法与CMR获得的RVol的相关性和一致性。采用Cohen′s Kappa系数分析三种PISA法定量分级结果与美国超声心动图学会(ASE)多参数法准确诊断重度二尖瓣反流(sMR)的一致性。结果DMR瞬时流量曲线呈单峰,在收缩中晚期达到峰值。PISA max、PISA pair法获得的RVol与CMR中度相关(r=0.77、0.80,均P<0.001),PISA M-mode获得的RVol与CMR强相关(r=0.87,P<0.001)。PISA max获得的RVol显著大于CMR[(69.1±37.1)ml比(49.0±29.0)ml,P=0.002]。PISA max和PISA pair定量分级结果与ASE多参数法准确诊断sMR均为中度一致性(RVol:κ=0.496、0.525,均P<0.001;EROA:κ=0.570、0.578,均P<0.001),而PISA M-mode与ASE多参数法结果为强一致性(RVol:κ=0.867,EROA:κ=0.802,均P<0.001)。结论由于DMR患者瞬时流量在收缩期呈单峰曲线模式,PISA max可能严重高估RVol及sMR的比例,而使得部分非sMR患者接受不必要的手术治疗。而PISA M-mode与CMR在定量RVol方面的相关性及一致性均优于PISA max及PISA pair,或许能改善和提高PISA法定量DMR严重程度的准确性。

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(PISAM-mode),and a time-integrated curve was plotted.Regurgitant volume(RVol)and effective regurgitant orifice area(EROA)were calculated by traditional PISA(PISAmax),pair PISA(PISApair),and PISAM-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 PISAmax and PISApair(r=0.77,0.80,both P<0.001),whereas PISAM-mode presented strong correlation with CMR(r=0.87,P<0.001).RVol acquired from PISAmax was larger than that of CMR[(69.1±37.1)ml vs(49.0±29.0)ml,P=0.002].Both PISAmax and PISApair 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 PISAM-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,PISAmax may significantly overestimate RVol,exposing a significant proportion of patients with DMR to unnecessary MR surgery.PISAM-mode presents better correlation and consistency with CMR on the quantification of RVol compared with PISAmax and PISApair,and may improve the diagnostic accuracy of quantification of sMR using PISA.