Simonson J S, Schiller N B
Department of Medicine, University of California School of Medicine, San Francisco 94143-0214.
J Am Soc Echocardiogr. 1989 Jan-Feb;2(1):25-35. doi: 10.1016/s0894-7317(89)80026-4.
Mitral annular apical systolic excursion or descent of the base (DB) of the left ventricle has been qualitatively observed by two-dimensional echocardiography studies to decrease as left ventricular systolic function deteriorates. On the basis of this observation a quantitative assessment of DB was examined as a means to estimate left ventricular ejection fraction (LVEF). Two-dimensional echocardiographic apical images were obtained in 100 subjects, 26 normal individuals and 74 clinical patients. Major diagnoses in the clinical patients were dilated cardiomyopathy in 24, coronary artery disease in 13, valvular disease in 16, left ventricular hypertrophy in 8, and no evident heart disease in 12. Wall motion was visually assessed; 22 subjects had a segmental wall motion abnormality, and 21 had a diffuse wall motion abnormality. All patients had a complete Doppler examination, and 31 had mitral and/or aortic regurgitation judged to be 2+ (moderate) or greater in severity. To quantitate DB the difference of the distance from the apex of the sector fan to the middle-mitral annular plane between end-diastole and end-systole in both two- and four-chamber views was calculated. Left ventricular end-diastolic volume and LVEF were calculated with a modified Simpson's rule algorithm applied to planimetered apical two- and four-chamber images. The mean DB of the normal subjects was 12 +/- 2 mm with both two- and four-chamber images. All normal subjects had a DB of 8 mm or greater. LVEF in percentage was linearly related to DB (millimeters) as follows. Two-chamber view, LVEF = 3.8 DB + 21; r = 0.78; standard error of the estimate = 14% Four-chamber view, LVEF = 4.1 DB + 17; r = 0.84; standard error of the estimate = 12% A four-chamber DB of less than 8 mm was associated with a depressed LVEF (less than 50%) with 82% specificity and 98% sensitivity. DB for a given LVEF was slightly increased in patients with 2+ or greater mitral and/or aortic regurgitation (p less than 0.001). Similarly, DB for a given LVEF in patients with a diffuse wall motion abnormality was slightly increased compared with those patients with a segmental wall motion abnormality (p less than 0.001). Comparison of left ventricular end-diastolic volume to DB showed a poor linear correlation. In conclusion, DB quantitation provides a useful, noninvasive method to estimate LVEF.
二维超声心动图研究已定性观察到，随着左心室收缩功能恶化，二尖瓣环的收缩期心尖偏移或左心室底部下降（DB）会减小。基于这一观察结果，对DB进行了定量评估，作为估计左心室射血分数（LVEF）的一种方法。在100名受试者中获取了二维超声心动图心尖图像，其中26名是正常个体，74名是临床患者。临床患者的主要诊断包括：扩张型心肌病24例，冠状动脉疾病13例，瓣膜病16例，左心室肥厚8例，12例无明显心脏病。通过视觉评估室壁运动；22名受试者存在节段性室壁运动异常，21名存在弥漫性室壁运动异常。所有患者均进行了完整的多普勒检查，31名患者的二尖瓣和/或主动脉反流程度被判定为2+（中度）或更高。为了定量DB，计算了两腔心和四腔心视图中舒张末期和收缩末期从扇形扇尖到二尖瓣环中间平面距离的差值。应用改良的辛普森法则算法，对心尖两腔心和四腔心图像进行面积测量，计算左心室舒张末期容积和LVEF。正常受试者的两腔心和四腔心图像的平均DB为12±2mm。所有正常受试者的DB均为8mm或更大。LVEF百分比与DB（毫米）呈线性相关，如下所示。两腔心视图：LVEF = 3.8DB + 21；r = 0.78；估计标准误差 = 14% 四腔心视图：LVEF = 4.1DB + 17；r = 0.84；估计标准误差 = 12% 四腔心DB小于8mm与LVEF降低（小于50%）相关，特异性为82%，敏感性为98%。二尖瓣和/或主动脉反流程度为2+或更高的患者，给定LVEF时的DB略有增加（p < 0.001）。同样，与节段性室壁运动异常的患者相比，弥漫性室壁运动异常的患者给定LVEF时的DB略有增加（p < 0.001）。左心室舒张末期容积与DB的比较显示线性相关性较差。总之，DB定量提供了一种有用的非侵入性方法来估计LVEF。
