单平面及双平面面积-长度法计算右心室容积的比较

Comparison of single-plane and biplane area-length methods for right ventricular volume calculation

目的 比较单平面和双平面面积 -长度法计算右心室容积和射血分数的相对准确性。方法对 1 5只人右心室铸型和 45例患者分别进行研究。单平面面积 -长度法计算右心室容积由心尖四腔观右室面积和心尖至三尖瓣环距离的乘积算得 ;双平面面积 -长度法计算右心室容积由心尖四腔观右心室面积与肺动脉瓣至三尖瓣距离乘积的 2 / 3算得。右室铸型的实际容积由铸型排除水的体积计算 ;活体的标准右心室容积和射血分数由X线右心室造影计算。结果 铸型研究表明 ,单平面和双平面法计算的右心室容积均与铸型的实际容积高度相关 (r分别为 0 .87和 0 .91 ,P <0 .0 0 1 ) ,但均显著高估铸型的实际容积 [分别高估 (50 .82± 35 .43)ml及 (30 .43± 2 0 .98)ml,P <0 .0 0 1 ]。单平面及双平面法计算的右心室容积之间亦高度相关 (r =0 .95 ,P <0 .0 0 1 )。活体研究表明 ,单平面和双平面法计算的右心室容积均与右心室造影容积高度相关 (r≥ 0 .98,P <0 .0 0 1 ) ;单平面法计算的右心室容积明显高估相应的右心室造影值(P <0 .0 0 1 ) ,双平面法右心室容积的计算值与X线右心室造影计算值差异无显著性意义 (P >0 .0 5)。单平面及双平面法计算的右心室射血分数与X线右心室造影值相比差异均无显著性意义 (P >0 .0 5)且高度相关

Objective To compare the relative accuracy of single-plane and biplane area-length methods for determining right ventricular (RV) volume and ejection fraction (RVEF) both in vitro and in vivo studies. Methods The in vitro study consisted of 15 human right ventricular casts and the in vivo study consisted of 45 patients. RV volume by single-plane area-length method was determined by the product of RV area from apical four-chamber view and the distance from RV apex to tricuspid annulus. RV volume by biplane area-length method was defined as 2/3×(the product of RV area from apical four-chamber view and the distance from pulmonary valve to tricuspid valve). The actual volume of RV casts was determined by water displacement method. RV angiography was used to determine RV volumes and RVEF in the in vivo study. Results RV volumes calculated from both single-plane and biplane methods correlated closely with RV cast volumes in the in vitro study (r= 0.87- and 0.91-, respectively; both P< 0.001-). However, both methods overestimated the actual volumes (P< 0.001-). RV volume from single-plane method also correlated closely with that from biplane method. The in vivo study showed that RV volumes from single-plane and biplane methods correlated highly with those from RV angiography (both r≥ 0.98-, P<- 0.001-). There was no significant difference between RV volumes from biplane method and those from angiography (P> 0.05-), but RV volume determined by single-plane method significantly overestimated angiographic volume (P< 0.001-). RVEF from both methods correlated closely with that from RV angiography (both r= 0.99-), and there was no significant difference between the echocardiographic values and RV angiographic values. Conclusions Both single-plane and biplane area-length methods can be used to evaluate RVEF accurately. The biplane method is more accurate than the single-plane method for calculating RV volume.