Clinical Study Of Quantitative Evaluation Of Valvular Regurgitation By Real-time Tri-plane Echocardiography

The two-dimension color Doppler flow imaging echocardiography (2D CDFI) is the main method of qualitation and quantitation to diagnose valvular regurgitation at present clinically, but the 2D CDFI can not demonstrate the space shape of regurgitation jet truly sometimes and it's accuracy is relatively poor in that the 3D shape of regurgitation jet is assessed only by length, width or area on 2D sections, especially when in the case of eccentrical regurgitation jet. With the development of real time three-dimension color Doppler flow imaging echocardiography (RT-3D CDFI), many scholars have demonstrated 3D CDFI is better than 2D CDFI and has fairly good correlation with the gold standard. But at the present, RT-3D CDFI still has some limitations with image quality and calculation in measurement. Based on RT-3D, Real-time tri-plane echocardiography (RT-3PE) can display three-dimensional shape of valve regurgitation and calculate out valve regurgitation volume in real time, providing a kind of new methods to estimate valve regurgitation quantitatively with more accuracy. The value of RT-3PE in the estimation of valve regurgitation was compared with other semi-quantitative methods and angiography.ObjectiveThe mitral maximal regurgitation jets area / left atrium area (RJA/LAA) and the aortic maximal regurgitation jets height /l eft ventricular outflow tract height (RJH/LVOTH) by 2D CDFI, the regurgitation jets volume / left atrium volume(RJV/LAV) by RT-3PE, and the regurgitation fraction (RF) by 2-dimensional color Doppler flow convergence (FC) method were obtained and their semi-quantitative classification was compared with angiographic classification in order to provide a convenient, accurate and reliable modality in quantitative evaluation for valve regurgitation.MethodsFrom July 2005 to July 2006, 40 patients with simple mitral regurgitation and 18 with simple aortic regurgitation by 2D CDFI were enrolled in the study. Of them, the eccentric jets were found in 18 and central jets in 30. The age was ranged from 16 to 80 years old and the mean age was 49±7.8 years. Intracardiac shunt, atrial fibrillation , atrioventricular conduction block ( above II degree), frequently premature ventricular contraction, severity bellows affection were excluded. GE Vivid7 Dimension color Doppler ultrasound mechine with RT-3PE imaging software was used. First, the routine examination was carried out and the images of the maximal regurgitation jet were obtained. Mitral maximal regurgitation jets area (RJA) and the same frame of left atrium area (LAA) or aortic maximal regurgitation jets height (RJH) and left ventricular outflow tract height(LVOTH) was measured and the average value of 3 times was obtained. The degree classification of mitral or aortic regurgitation was carried out baed on the ratio. For flow convergence (FC), the standard apical four-chamber view was obtained with confusion stack speed of color Doppler 39-46cm/s, scans depth at 16cm, scans angle <30', and direction was consistent with bloodstream direction. A bloodstream convergency area from valve regurgitation orifice end was observed one by one frame , color bloodstream turnover interface radius (r) from the best hemisphere convergency form was measured. The transient regurgitation ratio formula and regurgitation sustained time (Tr) were applied , regurgitation volume was calculated according to the formula as follows ( RV)=2πr2×Vn×Tr . Left ventricle end-diastole (EDV) and end-systolic volume (ESV) and stroke volumn (SV) were determined by Simpson method. The regurgitation fraction (RF) was calculated based on the formula as MVRF = RV/SV + RV and AVRF = RV/SV. We measured average value of three times . For RT-3PE, change 4VC transducer was used and standard apical four-chamber view was obtained and regurgitation border was displayed clearly. We adjusted the instrument to RT-3PE condition, the color regurgitation and left atria and ventricle images were able to be exhibited at the same time in three different azimuth pictures.We stopped electrocardiogram arriving at period of contraction or diastolic and drew the outline of three bundle regurgitation area and extracted the maximal regurgitation column, computer voluntarily taken place regurgitation column form and regurgitation jets volume(RJV). We drew the outline of left atria and ventricle area ,computer gave out the left atria and ventricle volume (LAV, LVV); the ratiso of RJV/LAV and RJV/LVV were calculated three times and were classifies. The patients were check by the left ventriculography or aortic angiography within 24-48 hours. Based on the contrast material regurgitation density to the left atria and ventricle. we can divide the mitral or aortic regurgitation into the I ~ IV grade.Results1 The RT-3PE presentation of valvular regurgitation Of 58 patients , the image of mitral or aortic regurgitation were displayed well , among them 18 simple aortic regurgitation and 40 simple mitral regurgitation with 40 central jets and 18 eccentric jets.2 Comparison between RT-3PE, 2DCDFI, FC and cardiac angiography method of quantify 58 mitral or aorta regurgitation: Compared with angiographic degree of valvular regurgitation, the coincidence ofⅠ,Ⅱ,Ⅲ,Ⅳdegree were 100%,73%,81%,82%by RT-3PE(Kappa value = 0.79), 80%,67%,70%,76%by FC(Kappa value =0.63), and 80%,67%,63%,70 % by RJA/LAA or RJH/LVOTH (Kappa value =0.59) respectively.3 The RT-3PE displayed and measured eccentric jets Compared with 2D CDFI display, RT-3PE not only displayed directly space direction and form of eccentric jets volume ,but accurately calculated the percentage of accounting corresponding volume.RT-3PE, 2D-CDFI and FC compared with cardiac angiography method: Of 18 patients with eccentric jets, the coincidence by RT-3PE was 78% with 4 underestimated; that by FC was 67% with 3 underestimated and 3 overestimated; and that by RJA/LAA of RJH/LVOTH was 56% with 8 underestimated.4 Repeatability comparisonRandom selection of 10 patients , the concordance between two observers and the same observer what two time measures value is 92% and 93% respectively. ConclusionRT-3PE is a convenient, accurate and reliable modality in quantitative evaluation for valvular regurgitation. Compared with angiographic degree, the consistency is good and it is especially usable for eccentric regurgitation jets.