Ballester M, Rickards A, Rees S, McDonald L
Eur Heart J. 1983 Dec;4(12):846-53. doi: 10.1093/oxfordjournals.eurheartj.a061412.
Different cross-sectional echocardiographic patterns of systolic anterior motion of the mitral valve (SAM) have been observed in patients with hypertrophic cardiomyopathy. chordae tendineae and/or the free edge of the mitral valve were seen to be involved in some: SAM(c). The body of the mitral valve encroached upon the left ventricular outflow tract in this movement in a second group: SAM(v). Other patients did not show SAM. A study of 27 patients was performed to investigate the relationship of these patterns of SAM to the subaortic gradient as well as the prevalence and degree of mitral regurgitation. The absence of SAM correlated with no obstruction and 29% prevalence of mitral regurgitation. In SAM(c), the mean gradient was 10 +/- 10 mmHg. (0-35 mmHg), and mitral regurgitation involved 36% of the patients. In SAM(v) the mean gradient found was 81 +/- 37 mmHg (20-150), and 67% had mitral regurgitation. In situations where mitral regurgitation was most prevalent its degree was greatest.
(1) chordal or leaflet participation in SAM is relevant to the presence and degree of obstruction; (2) leaflet involvement usually implies severe obstruction; (3) distortion of the mitral valve apparatus may contribute to the genesis of mitral regurgitation.
肥厚型心肌病患者中观察到二尖瓣收缩期前向运动（SAM）有不同的横断面超声心动图表现。在一些患者中可见腱索和/或二尖瓣游离缘参与其中：SAM（c）。在另一组患者中，二尖瓣体在该运动中 encroached upon 左心室流出道：SAM（v）。其他患者未表现出SAM。对27例患者进行了一项研究，以调查这些SAM模式与主动脉下梯度以及二尖瓣反流的发生率和程度之间的关系。无SAM与无梗阻和29%的二尖瓣反流发生率相关。在SAM（c）中，平均梯度为10±10 mmHg（0 - 35 mmHg），36%的患者存在二尖瓣反流。在SAM（v）中，平均梯度为81±37 mmHg（20 - 150），67%的患者有二尖瓣反流。在二尖瓣反流最普遍的情况下，其程度最大。
（1）腱索或瓣叶参与SAM与梗阻的存在和程度相关；（2）瓣叶受累通常意味着严重梗阻；（3）二尖瓣装置的扭曲可能导致二尖瓣反流的发生。
“encroached upon”这里可能是“侵犯、侵占”之类意思，结合语境可能是二尖瓣体对左心室流出道有某种影响，但不太明确准确意思，暂保留原文。
