Department of Cardiology, Centre Hospitalier de Compiègne, Compiègne, France.
Departement of Cardiology, Centre Hospitalier Universitaire d'Amiens, Amiens, France.
Echocardiography. 2024 Aug;41(8):e15898. doi: 10.1111/echo.15898.
BACKGROUND/AIM: Left ventricular outflow tract obstruction related to systolic anterior motion (SAM) of the mitral valve is a common complication of dobutamine stress echocardiography (DSE). However, the mechanisms underlying SAM have not been fully characterized. The objective of the present study was to use three-dimensional echocardiography to identify anatomic features of the mitral valve that predispose to SAM during DSE.
We retrospectively evaluated consecutive patients included prospectively in our database and who had undergone 3D echocardiography (including an assessment of the mitral valve) before DSE. Patients who had developed SAM during DSE (the SAM+ group) were matched 2:3 with patients who did not (the SAM- group).
One hundred patients were included (mean age: 67 ± 10). Compared with SAM- patients (n = 60), SAM+ patients (n = 40) had a lower mitral annular area, a smaller perimeter, and a smaller diameter (p < .01 for all, except the anteroposterior diameter). The SAM+ group had also a narrower mitral-aortic angle (126 ± 12° vs. 139 ± 11° in the SAM- group; p < .01) and a higher posterior mitral leaflet length (1.4 ± .27 cm vs. 1.25 ± .29, respectively; p < .01). Furthermore, the mitral annulus was more spherical, more flexible, and more dynamic in SAM+ patients than in SAM- patients (p < .05 for all). In a multivariate analysis of anatomic variables, the mitral-aortic angle, the mitral annular area, and posterior leaflet length were independent predictors of SAM (p ≤ .01 for all). In a multivariate analysis of standard echo and hemodynamic variables, the presence of wall motion abnormalities at rest (p < .01) was an independent predictor of SAM.
SAM during DSE is multifactorial. In addition to the pharmacologic effects of dobutamine on the myocardium, 3D echocardiographic features of the mitral valve (a smaller mitral annulus, a narrower mitral-aortic angle, and a longer posterior leaflet) appear to predispose to SAM.
背景/目的：左心室流出道梗阻与二尖瓣收缩期前向运动（SAM）有关，是多巴酚丁胺负荷超声心动图（DSE）的常见并发症。然而，SAM 的发生机制尚未完全阐明。本研究旨在使用三维超声心动图识别 DSE 期间导致 SAM 的二尖瓣解剖特征。
我们回顾性评估了前瞻性纳入数据库并在 DSE 前接受三维超声心动图（包括二尖瓣评估）的连续患者。在 DSE 期间发生 SAM 的患者（SAM+组）与未发生 SAM 的患者（SAM-组）按 2:3 配对。
共纳入 100 例患者（平均年龄 67±10 岁）。与 SAM-患者（n=60）相比，SAM+患者（n=40）的二尖瓣环面积较小，周长较小，直径较小（除前后径外，所有指标均 p<0.01）。SAM+组的二尖瓣-主动脉角也较窄（126±12° vs. 139±11°在 SAM-组；p<0.01），后二尖瓣叶长度较长（1.4±0.27cm vs. 1.25±0.29cm；分别；p<0.01）。此外，SAM+患者的二尖瓣环更圆，更灵活，更具动态性（所有指标均 p<0.05）。在解剖学变量的多变量分析中，二尖瓣-主动脉角、二尖瓣环面积和后瓣叶长度是 SAM 的独立预测因子（所有指标 p≤0.01）。在标准超声心动图和血流动力学变量的多变量分析中，静息时存在壁运动异常（p<0.01）是 SAM 的独立预测因子。
DSE 期间的 SAM 是多因素的。除了多巴酚丁胺对心肌的药理学作用外，二尖瓣的 3D 超声心动图特征（较小的二尖瓣环、较窄的二尖瓣-主动脉角和较长的后瓣叶）似乎也易导致 SAM。
