Department of Cardiovascular Surgery, University Medical Centre Freiburg, Freiburg, Germany.
Ann Thorac Surg. 2011 Mar;91(3):709-14. doi: 10.1016/j.athoracsur.2010.09.038.
Preoperative assessment of aortic annulus diameter is crucial for valve sizing in patients scheduled for transcatheter aortic valve replacement. Computed tomographic (CT) measurements of the aortic annulus are not standardized and may yield different results depending on view due to its elliptic shape. The purpose of this study was to compare the measurement of the aortic annulus during surgery in patients undergoing conventional aortic valve replacement with noninvasive methods.
In 33 patients with aortic valve stenosis (18 males, mean age 77.2 ± 7.9), aortic annulus diameter was measured with cardiac CT and TEE (transesophageal echocardiography) prior to open aortic valve replacement. In CT, aortic annulus diameter was assessed as the calculated average diameter of luminal area at the level of basal attachments of the leaflets by means of planimetry. Operative measurements were performed with a Hegar dilator. A Pearson analysis was applied to test for degree of correlation.
Calculated average diameter by CT correlated significantly with intraoperative measurements (r = 0.923, p < 0.001) and with the size of implanted valve (r = 0.867, p < 0.001), while correlation of TEE and intraoperative measurements was weak (r = 0.523, p = 0.002). The TEE tends to underestimate the dimensions of aortic annulus.
The CT-measured aortic annulus diameter, assessed as the calculated average diameter of planimetric annulus area, seems to provide adequate dimensions similar to operative measurements with a Hegar dilator. This approach may minimize the dependency of single-view CT measurement on the elliptic shape of the aortic annulus and appears to be a feasible alternative for aortic annulus assessment in terms of candidates' selection for transcatheter aortic valve replacement.
经导管主动脉瓣置换术（TAVR）前评估主动脉瓣环直径对瓣膜尺寸的选择至关重要。由于主动脉瓣环呈椭圆形，其 CT 测量值未标准化，可能会因视图而异而产生不同的结果。本研究旨在比较 TAVR 患者术中主动脉瓣环的测量值与非侵入性方法。
在 33 例主动脉瓣狭窄患者（男性 18 例，平均年龄 77.2±7.9 岁）中，在接受开放式主动脉瓣置换术前，通过心脏 CT 和 TEE（经食管超声心动图）测量主动脉瓣环直径。在 CT 中，通过计算瓣叶基底部附着处管腔面积的平均直径来评估主动脉瓣环直径。术中测量使用 Hegar 扩张器进行。应用 Pearson 分析来检验相关性程度。
CT 计算的平均直径与术中测量值（r=0.923，p<0.001）和植入瓣膜的大小（r=0.867，p<0.001）显著相关，而 TEE 与术中测量值的相关性较弱（r=0.523，p=0.002）。TEE 往往低估主动脉瓣环的尺寸。
CT 测量的主动脉瓣环直径，评估为计算的面积法平均瓣环面积，似乎与使用 Hegar 扩张器的术中测量值提供相似的充分尺寸。这种方法可能会最小化基于主动脉瓣环椭圆形的单视图 CT 测量的依赖性，并在经导管主动脉瓣置换术候选者选择方面，似乎是一种可行的主动脉瓣环评估替代方法。
