彩色多普勒血流会聚法定量二尖瓣返流的临床探讨

为探讨临床应用彩色多普勒血流会聚法定量评价二尖瓣返流，本文采用心脏造影－热稀释方法作对照，研究２２例二尖瓣返流患者，发现会聚法测得的每搏返流量、返流分数与心导管法浊值总体相关良好（ｒ分别为０．９３－０．９４，０．８１－０．８７）。会聚方法（１）计算的每搏返流量值与心导管法测值无显著差异，而会聚方法（２）的每搏返流量测值出现低估。会聚方法（１）能直接较准确计算每搏返流量，但不能直接提供返流分烽，该方     

彩色多普勒血流会聚与众射流参数在二尖瓣返流定量中的价值

用血流会聚新方法及射流参数对二尖瓣返流定量的价值进行了研究。结果表明血流会聚法计算返流量与二尖瓣返流容积及返流分数相关性最佳。彩色多普勒射流参数与二尖瓣返流容积和二尖瓣返流分数的相关性不一，其中返流起始宽度与两者相关性分别为ｒ＝０．８７－０．９３，Ｐ＜０．０００１）．彩色多普勒射流参数与二尖瓣返流容积和二尖瓣返流分数的相关性不一，其中返流起始宽度与两者相关性分别为ｒ＝０．８８和０．８１（Ｐ＜０．０     

彩色多普勒血流会聚法定量评估二尖瓣返流严重程度的研究

彩色多普勒血流会聚区（ＦＣＲ）法是近几年发展起来的一定量二尖瓣返流的新方法。本文应用该方法，对５５例显示血流会聚区的二尖瓣返流患者行ＦＣＲ法与返流束面积法（ＳＲ）、返流束面积与左房面积之比法（ＳＲ／ＳＬＡ）相比较，相关系数分别为０．８２２及０．７３２（Ｐ值均小于０．０１），并应用ＦＣＲ法定量测定二尖瓣返流率。按不同的返流率将二尖瓣返流分为轻、中、重三度。本文认为血流会聚法为定量评估二尖瓣返流（特别是中至重度返流）一较为理想的无创性方法，具有广泛的理论研究及临床应用前景。     

彩色多普勒血流会聚法对偏心性二尖瓣返流程度的评估

作者2000年3月～2001年9月,将彩色多普勒血流会聚法用于评估偏心性二尖瓣返流的程度,与返流束面积法进行对照,探讨彩色多普勒血流会聚法在判断偏心性二尖瓣返流程度的临床价值.     

改良法二尖瓣返流量计算方法的可行性研究

通过４３例不同程度的二尖瓣返流的定量诊断研究，提出了一种利用彩色多普勒血流会聚法与脉冲多普勒技术计算二尖瓣返流量的改良方法，即Ｖ＝Ｑ．Ｔｐ（其中Ｖ代表二尖瓣每搏返流量，Ｑ为返流率，Ｔｐ为返流持续时间）。研究表明，改良法不仅克服了目前的二尖瓣返流量计算方法的缺点，而且简化了计算方法，是一种准确、可靠且实用的二尖瓣返流量计算方法。     

超声多普勒测定二尖瓣返流的有效返流口面积

为探讨返流口面积大小对评价二尖瓣返流（ＭＲ）严重性的价值，对３５例ＭＲ患者进行了多普勒超声有效返流口面积（ＲＯＡ）测定及心导管检查。发现彩色多普勒血流会聚法（ＦＣＭ）及多普勒血流量法测得的ＲＯＡ与心导管左室造影返流程度，每搏返流量及返流分数均密切相关（相关系数分别为０．８６，０．８４；０．８９，０．８７；０．８０，０．７８；Ｐ＜０．００１）。两种超声方法的ＲＯＡ测值总体上无显著差异（Ｐ＞０．０５），但ＦＣＭ的结果优于多普勒血流量法，且ＦＣＭ计算ＲＯＡ更为方便。本文亦提出以ＲＯＡ估计ＭＲ程度的定量标准。     

以立体角代替平面角彩色多普勒血流会聚法评估三尖瓣返流程度

目的　探讨彩色多普勒血流会聚法在评估三尖瓣返流程度中的应用价值。方法　应用不同的血流会聚方程对３２例三尖瓣返流患者的返流程度进行测量, 并与传统法所测指标进行比较。结果　应用立体角会聚方程计算的返流率（Ｆ２）与传统方法测得的返流束指标ＳＲ／ＳＲＡ、ＶＰ 以及二维多普勒方法计算的每搏返流量Ｑ之间的相关关系（ｒ分别为０．４８, ０．４６, ０．９８）优于应用平面角会聚方程计算的返流率（Ｆ１）, 与上述指标之间的相关关系（ｒ分别为０．４６, ０．４４, ０．９２）。而且ＳＶ１明显低估返流程度,ＳＶ２更接近于实际值。结论　应用立体角会聚方程代替平面角会聚方程能更为准确地评估三尖瓣返流程度     

测量有效返流口面积在二尖瓣关闭不全定量诊断中的价值

用彩色多普勒血流会聚方法测量了二尖瓣有效返流口面积，并探讨了该指标在二尖瓣关闭不全定量诊断中的价值。结果表明，这一指标与二尖瓣返流容积、返流分数，彩色多普勒返流起始宽度、返流面积具有良好的相关性（分别为ｒ＝０．８９、０．８４、０．８２及０．６７，Ｐ＜０．００１～０．０００１）。有效返流口面积≥３０ｍｍ２区别轻、中度与重度返流的准确度为９５．７％。有效返流口面积是一种较好的反映二尖瓣关闭不全的指标。     

彩色多普勒血流会聚法定量二尖瓣返流的临床应用

为在临床上应用彩色多普勒血流会聚法定量评价二尖瓣返流，本文应用频谱多普勒法评估二尖瓣返流作对照，评价其定量返流的临床应用价值，文中研究了２４例二尖瓣返流患者，用二维超声心动图计算出主动脉瓣口和二尖瓣口的面积，用频谱多普勒计算出收缩期主动脉瓣口血流的速...     

彩色多普勒过返流口宽度与射流参数评估二尖瓣返流的对照研究

目的：研究彩色多普勒过返流口宽度评估二尖瓣返流的价值。材料与方法：测量３１例二尖瓣关闭不全患者彩色多普勒过返流口宽度、返流长度、返流面积、瞬间返流容积及返流量和返流分数。结果：彩色多普勒过返流口宽度、返流长度、返流面积及瞬间返流容积与返流量的相关性分别为ｒ＝０．８７、０．４８、０．６５和０．６４；上述彩色多普勒参数与返流分数的相关性分别为ｒ＝０．８９、０．６１、０．７１和０．６４。彩色多普勒过返流口宽度预报重度二尖瓣返流的准确度（９３．５％～９６．８％）显著高于返流长度、返流面积及瞬间返流容积预报重度二尖瓣返流的准确度（７１．０％～７４．２％），Ｐ＜０．０５～０．０１。结论：彩色多普勒过返流口宽度是一种比返流束更好的评估二尖瓣返流的指标。     

磁共振相位编码速度标识技术在儿童二尖瓣反流定量分析中应用

目的利用磁共振相位编码速度标识技术对儿童二尖瓣反流作定量分析。方法本组二尖瓣反流组共19例,男11例,女8例。正常对照组10例,男5例,女5例。19例二尖瓣反流病人先行心脏超声检查,利用半定量方法,诊断19例二尖瓣反流,轻度反流5例,中度反流10例,重度反流4例。利用磁共振的相位编码速度标识技术分别对正常对照组、二尖瓣轻、中、重度反流的病例进行左心室流入量和主动脉流量测定,随后对所测的结果进行统计学分析。结果在正常对照组中,左心室流入量与主动脉流量之间的相关性良好。正常组与轻度二尖瓣反流反流量与反流指数无显著性差异,正常组分别与中度、重度二尖瓣反流组反流量与反流指数有显著性差异,轻、中、重度二尖瓣反流组间有显著性差异,二尖瓣反流指数与超声的二尖瓣反流程度的估计相关性良好。结论磁共振相位编码速度标识技术为非创伤检查中对儿童二尖瓣反流定量分析的较好方法,并为以后的外科手术以及术后随访提供更为精确的信息。     

Accuracy and feasibility of a simplified approach to assess the regurgitant orifice area in patients with mitral regurgitation

BACKGROUND: Regurgitant orifice area (ROA) has been proposed as a marker of severity in patients with mitral regurgitation (MR). However, such fundamental quantitative echocardiographic parameter has failed to achieve widespread use, since it is difficult to measure. In the present study, we evaluated the accuracy and feasibility of a simplified method for quantification of ROA in patients with varying grades of MR. METHODS: We studied two groups of individuals with echocardiographically diagnosed MR. Group I included 70 patients retrospectively evaluated, in whom we were able to obtain an adequate flow convergence region by color Doppler and recording of continuous-wave Doppler regurgitant jet. Group II included 32 MR patients prospectively evaluated. The degee of MR was assessed by two quantitative echocardiographic measures: the regurgitant fraction and the ROA, calculated either dividing peak flow rate by the maximal velocity through the orifice or with the simplified formula: r2/2. RESULTS: In group I, the mechanism of MR was organic in 18 patients and ischemic/functional in 52 patients. ROA calculated by the simplified formula correlated well with the conventional one (r = 0.85) and with the regurgitant fraction (r = 0.72). In group II, we could calculate the ROA by the conventional method in 56% of patients, whereas use of the simplified approach allowed ROA evaluation in 78% of patients. CONCLUSION: Our data suggest that the use of a simplified formula may increase the number of patients having ROA, a fundamental parameter of MR severity, measured in clinical practice.     

彩色多普勒血流会聚法评估偏心性二尖瓣返流的临床价值

观察３０列显示血流会聚区的偏心性二尖瓣返流患者的返流束形态，发现均为附壁细长束。返流束面积、返流束面积／左房面积与频谱多普勒法及血流会聚法测定的参数比较左相关性均较差，相关系数分别为０．５９、０．５６及０．５５、０．５７，耐血流会聚法所测返流率与频谱多普勒法所测返流量则高度相关，相关系数为０．９６（Ｐ＜０．０１）。     

Usefulness of the mitral/aortic flow velocity integral ratio as a screening method to identify patients with hemodynamically significant mitral regurgitation.

OBJECTIVE: We sought to test the value of a simple Doppler index, the mitral/aortic flow velocity integral ratio (MAVIR), as a screening method to identify patients with hemodynamically significant mitral regurgitation (MR). METHODS: Included in the study were 91 patients (mean age 61 +/- 14 years; 54% men) with echocardiographically diagnosed MR. The cause was organic in 23 patients and ischemic/functional in 68. MR degree was assessed by 2 quantitative echocardiographic measures: the regurgitant fraction and the regurgitant orifice area. RESULTS: A good correlation was found between MAVIR and both regurgitant fraction (r = 0.75) and orifice (r = 0.60). When we divided patients into 3 groups on the basis of the regurgitant fraction, used as reference standard, MAVIR significantly increased in proportion to MR severity (0.7 +/- 0.1 for mild MR vs 1.1 +/- 0.2 for moderate and 1.4 +/- 0.3 for severe regurgitation; P <.0001). A ratio > 1 identified 28 of 30 patients with severe MR (regurgitant fraction > 60%), whereas all patients with mild MR (regurgitant fraction < 40%) had a ratio < 1. Using a regurgitant orifice >or= 40 mm(2) as threshold for severe MR, a significant difference in MAVIR was also present among patients who had severe MR compared with those having mild and moderate regurgitation (P <.0001). CONCLUSIONS: These findings suggest that MAVIR is a sensitive index, potentially widely applicable in clinical practice as a screening parameter for identifying patients with hemodynamically significant MR.     

多普勒超声和心导管同步测量二尖瓣返流患者左室收缩功能的研究

本文在25例二尖瓣返流患者中,利用多普勒超声和双心导管技术同步测量了静息和负荷状态下30例次的左室收缩功能。结果显示。连续波多普勒测量的二尖瓣返流压差最大上升速率与心导管测量的左室压力最大上升速率(dp/dtmax)高度相关(r=0.87)。而脉冲波多普勒测量的升主动脉血流最大速度和平均加速度与心导管测量的dp/dtmax无显著相关(r分别为—0.18。0.07)。表明连续波多普勒超声心动图是估测二尖瓣返流患者左室dp/dtmax的可靠技术。     

Severity of mitral and aortic regurgitation as assessed by cardiovascular magnetic resonance: optimizing correlation with Doppler echocardiography.

BACKGROUND: Cardiovascular magnetic resonance (CMR) is widely recognized as a non-invasive gold standard for quantification of ventricular volumes. In addition, it is an emerging diagnostic modality for clinical evaluation of mitral regurgitation (MR) and aortic regurgitation (AR). CMR facilitates accurate quantitation of regurgitation volumes and regurgitant fraction, but referring physicians are often more comfortable with qualitative measures, and few data exist for correlation of qualitative CMR regurgitation severity with that obtained by more conventional qualitative Doppler echocardiography. Because patients with AR and MR may commonly be assessed by both echocardiography and CMR modalities, consistency between qualitative gradient of regurgitation severity is important for follow-up. Therefore, we sought to define the CMR regurgitant fractions that best correlate with qualitative mild, moderate, and severe regurgitation by color Doppler echocardiography. METHODS AND RESULTS: Data from 141 consecutive patients (age 53 +/- 15 yr; 43% female) with contemporary (median, 31 days) CMR and echocardiographic data, including 107 regurgitant valves and 70 normal valves, were compared. Thresholds were developed on an initial cohort of patients with 55 regurgitant valves, and subsequently tested on a later cohort of patients with 52 regurgitant valves. Regurgitation fraction (RF) limits that optimized concordance of CMR and echo severity grades were similar for MR and AR and were: mild < or = 15%, moderate 16-25%, moderate-severe 26-48%, severe > 48%. CONCLUSIONS: The current study provides simple qualititative threshold grades for MR and AR severity that allows for standardized reporting of regurgitation severity by CMR and excellent correlation with clinical echocardiography.     

二尖瓣反流束的彩色三维超声重建

目的　探讨三维彩色多普勒超声在二尖瓣反流定量诊断方面的应用价值。方法　运用彩色三维多普勒超声对 3 1例二尖瓣反流患者进行反流束的三维重建 ,选择反流束最大时的图像 ,手动勾画反流束外边界。以VRML及Excel表格两种模式输出报告 ,分别显示所勾画的反流束形态及容积。结果　 3 1例患者中轻度反流 10例 ,反流束容积 <10ml ,皆为小火焰状。中度反流 11例 ,反流束容积 <3 0ml,皆呈火焰状或短棒状。重度反流 10例 ,反流束容积 >3 0ml,其中偏心型反流 7例 ,断面呈不规则半月形 ,反流束顶部常因血流折返而形成“分支”现象 ,其背面也可因反流束进入肺静脉而出现“出芽”现象 ;中央型反流 3例 ,呈棍棒状。结论　三维彩色多普勒超声提供了一个从空间立体的角度评价瓣膜反流的新方法 ,将超声对反流的定量提高到一个新的精确度。     

A novel technique to quantify the instantaneous mitral regurgitant rate

Background

The systolic variation of mitral regurgitation (MR) is a pitfall in its quantification. Current recommendations advocate using quantitative echocardiographic techniques that account for this systolic variation. While prior studies have qualitatively described patterns of systolic variation no study has quantified this variation.

Methods

This study includes 41 patients who underwent cardiovascular magnetic resonance (CMR) evaluation for the assessment of MR. Systole was divided into 3 equal parts: early, mid, and late. The MR jets were categorized as holosystolc, early, or late based on the portions of systole the jet was visible. The aortic flow and left ventricular stroke volume (LVSV) acquired by CMR were plotted against time. The instantaneous regurgitant rate was calculated for each third of systole as the difference between the LVSV and the aortic flow.

Results

The regurgitant rate varied widely with a 1.9-fold, 3.4-fold, and 1.6-fold difference between the lowest and highest rate in patients with early, late, and holosystolic jets respectively. There was overlap of peak regurgitant rates among patients with mild, moderate and severe MR. The greatest variation of regurgitant rate was seen among patients with mild MR.

Conclusion

CMR can quantify the systolic temporal variation of MR. There is significant variation of the mitral regurgitant rate even among patients with holosystolic MR jets. These findings highlight the need to use quantitative measures of MR severity that take into consideration the temporal variation of MR.     

Regurgitant flow in apparently normal valve prostheses: improved detection and semiquantitative analysis by transesophageal two-dimensional color-coded Doppler echocardiography

In 128 patients with apparently normally functioning prosthetic valves (n = 136) in the aortic position (n = 79) and the mitral position (n = 57), the prevalence of transprosthetic regurgitant flow was studied by use of transthoracic and transesophageal two-dimensional color-coded Doppler echocardiography. With the transthoracic approach, regurgitant flow was detected in early systole or diastole for 28% of the mitral prostheses and for 29% of the aortic prostheses. With transesophageal color-coded Doppler echocardiography, regurgitant jets were visualized for 95% of the mitral prostheses and for 44% of the aortic prostheses. In 40% of the Bj?rk-Shiley prostheses and 88% of the St. Jude Medical prostheses in the mitral position, more than one jet with an eccentric origin was detected, whereas in bioprostheses only one centrally localized regurgitant jet was noted. The regurgitant jet length was 22 +/- 2 mm in mitral prostheses and 12 +/- 2 mm in aortic prostheses. The jet area was 154 +/- 31 mm2 in mitral prostheses and 61 +/- 26 mm2 in aortic prostheses. Jets of this size and frequency have to be considered a normal finding and the equivalent of regurgitant flow known from in vitro studies. We conclude that only transesophageal color-coded Doppler echocardiography seems to be a reliable method for following up mitral valve prostheses to detect and differentiate regurgitant jets. For aortic valve prostheses the advantage of transesophageal color-coded Doppler echocardiography does not seem to be as obvious as the advantage for mitral prostheses.