St. Paul's Hospital, University of British Columbia, Vancouver, Canada.
JACC Cardiovasc Interv. 2011 Nov;4(11):1235-45. doi: 10.1016/j.jcin.2011.07.014.
This study sought to determine the most reproducible multidetector computed tomography (MDCT) measurements of the aortic annulus and to determine methods to improve the applicability of these measurements for transcatheter aortic valve implantation.
The reproducibility and applicability of MDCT annular measurements to guide transcatheter aortic valve implantation remain unclear.
Annular measurements were performed in 50 patients planed for transcatheter aortic valve implantation in multiple planes: basal ring (short- and long-axis, mean diameter, area-derived diameter), coronal, sagittal, and 3-chamber projections. A theoretical model was developed taking into account the differences between the most reproducible MDCT measurements and transesophageal echocardiography to guide valve size choice.
The most reproducible measurements were the area-derived diameter and basal ring average diameter (inter-reader intraclass correlation coefficient: 0.87 [95% confidence interval: 0.81 to 0.92] and 0.80 [95% confidence interval: 0.70 to 0.87]; respectively; intrareader >0.90 for all readers). These were generally larger than transesophageal echocardiography diameters (mean difference of 1.5 ± 1.6 mm and 1.1 ± 1.7 mm, respectively). When a strategy of valve-sizing is undertaken using these CT measurements using an echocardiographic sizing scale, a different THV size would be selected in 44% and 40% of cases, respectively. When adjusting the sizing cutoffs to account for the differences in observed diameters, this was reduced to 10% to 12% (p < 0.01 for both, respectively).
The most reproducible MDCT measurements of the annulus are the area-derived diameter and basal ring average diameter, with derived values generally larger than those obtained with echocardiography. If MDCT is used for valve sizing, a strategy incorporating these differences may be important. MDCT using these easily derived measurements may be ideally suited to sizing transcatheter aortic valves as they account for the eccentricity of the aortic annulus, are reproducible, and are noninvasive.
本研究旨在确定主动脉瓣环最具可重复性的多层螺旋 CT（MDCT）测量方法，并确定提高这些测量方法在经导管主动脉瓣植入术中适用性的方法。
MDCT 瓣环测量指导经导管主动脉瓣植入术的可重复性和适用性尚不清楚。
在计划进行经导管主动脉瓣植入术的 50 例患者的多个平面进行瓣环测量：基底环（短轴和长轴、平均直径、面积直径）、冠状位、矢状位和 3 腔位。考虑到最具可重复性的 MDCT 测量值与经食管超声心动图之间的差异，建立了一个理论模型，以指导瓣膜尺寸选择。
最具可重复性的测量值是面积直径和基底环平均直径（读者间的组内相关系数：0.87[95%置信区间：0.81 至 0.92]和 0.80[95%置信区间：0.70 至 0.87]；分别；所有读者的内读 >0.90）。这些通常大于经食管超声心动图的直径（平均差值分别为 1.5±1.6 毫米和 1.1±1.7 毫米）。如果使用这些 CT 测量值并采用超声心动图尺寸分级策略进行瓣膜尺寸选择，分别有 44%和 40%的情况下会选择不同的 THV 尺寸。当调整尺寸截止值以考虑观察到的直径差异时，这一比例分别降低到 10%至 12%（p<0.01）。
主动脉瓣环最具可重复性的 MDCT 测量值是面积直径和基底环平均直径，其测量值通常大于经超声心动图获得的值。如果 MDCT 用于瓣膜尺寸选择，纳入这些差异的策略可能很重要。使用这些易于获得的测量值进行 MDCT 可能非常适合经导管主动脉瓣的尺寸测量，因为它们考虑到了主动脉瓣环的偏心性，具有可重复性，并且是非侵入性的。
