Wolff Ryan, Uretsky Seth
Carnegie Hill Radiology, New York, NY, USA.
Department of Cardiovascular Medicine, Morristown Medical Center, Gagnon Administration, Meade B, Morristown Medical Center, 100 Madison Ave, Morristown, NJ, 07960, USA.
Int J Cardiovasc Imaging. 2020 Nov;36(11):2221-2227. doi: 10.1007/s10554-020-01927-0. Epub 2020 Jul 6.
In bileaflet mitral valve prolapse (BMVP) systolic leaflet displacement creates a pocket of blood on the left ventricular (LV) side of the leaflets, but on the atrial side of the annulus. This blood is excluded from the LV end-systolic volume if the mitral valve annulus is used to determine the most basal extent of the LV. The purpose of this study is to describe the quantitative implications of defining the LV base on mitral regurgitant severity and LV systolic function in BMVP. In 30 consecutive patients (53% male, 58 ± 14 years) with BMVP, LV endocardial and epicardial borders were determined from SSFP images. The LV base at end-systole was defined by the "Functional" method (at the mitral valve annulus) or the "Anatomic" method (at the mitral valve leaflets). Regurgitant volume was the difference between the LV stroke volume and mean forward flow. LV myocardial strain measurements were determined from the short axis endocardial and epicardial borders. The "Functional" method resulted in higher regurgitant volumes (mean difference: 22 ml, range 0-40 ml) and higher ejection fractions (mean difference: 9%, range 0-21%). The correlation between LV end-diastolic volume and regurgitant volume was better with the "Functional" method (r = 0.79, p < 0.0001) than the "Anatomic" method (r = 0.67, p < 0.0001). The correlation between global myocardial radial strain and LV EF was better with the "Functional" method (r = 0.86, p < 0.0001) than the "Anatomic" method (r = 0.68, p < 0.0001). In BMVP, the base of the LV should be defined at the level of the mitral valve annulus so that regurgitant volume most accurately reflects the functional significance of the mitral valve disease and LVEF most accurately reflects global systolic LV function. Defining the basal extent of the LV at the mitral valve leaflets leads to substantially lower regurgitant volumes and lower ejection fractions that could have important clinical consequences.
在双叶二尖瓣脱垂（BMVP）中，收缩期瓣叶移位在瓣叶的左心室（LV）侧、但在瓣环的心房侧形成一个血池。如果使用二尖瓣环来确定左心室的最基底部范围，该血池不被计入左心室收缩末期容积。本研究的目的是描述在BMVP中基于二尖瓣反流严重程度和左心室收缩功能来定义左心室基部的定量意义。在30例连续的BMVP患者（男性占53%，年龄58±14岁）中，从稳态自由进动（SSFP）图像确定左心室内膜和外膜边界。收缩末期的左心室基部通过“功能”法（在二尖瓣环处）或“解剖”法（在二尖瓣瓣叶处）来定义。反流容积是左心室每搏量与平均前向流量之差。左心室心肌应变测量值由短轴内膜和外膜边界确定。“功能”法导致更高的反流容积（平均差异：22ml，范围0 - 40ml）和更高的射血分数（平均差异：9%，范围0 - 21%）。与“解剖”法（r = 0.67，p < 0.0001）相比，“功能”法测得的左心室舒张末期容积与反流容积之间的相关性更好（r = 0.79，p < 0.0001）。与“解剖”法（r = 0.68，p < 0.0001）相比，“功能”法测得的整体心肌径向应变与左心室射血分数之间的相关性更好（r = 0.86，p < 0.0001）。在BMVP中，左心室基部应在二尖瓣环水平定义，以便反流容积最准确地反映二尖瓣疾病的功能意义，左心室射血分数最准确地反映左心室整体收缩功能。将左心室基部范围定义在二尖瓣瓣叶处会导致反流容积和射血分数显著降低，这可能会产生重要的临床后果。
