Heart and Vascular Institute and Imaging Institute, the Cleveland Clinic, Cleveland, OH 44195, USA.
Circ Cardiovasc Imaging. 2011 Sep;4(5):566-73. doi: 10.1161/CIRCIMAGING.111.964916. Epub 2011 Jul 7.
In patients with aortic stenosis (AS), precise assessment of severity is critical for treatment decisions. Estimation of aortic valve area (AVA) with transthoracic echocardiographic (TTE)-continuity equation (CE) assumes a circular left ventricular outflow tract (LVOT). We evaluated incremental utility of 3D multidetector computed tomography (MDCT) over TTE assessment of AS severity.
We included 51 patients (age, 81±8 years; 61% men; mean gradient, 42 ± 12 mm Hg) with calcific AS who underwent evaluation for treatment options. TTE parameters included systolic LVOT diameter (D) and continuous and pulsed wave (CW and PW) velocity-time integrals (VTI) through the LVOT and mean transaortic gradient. MDCT parameters included systolic LVOT area, ratio of maximal to minimal LVOT diameter (eccentricity index), and aortic planimetry (AVA(p)). TTE-CE AVA [(D(2)×0.786×VTIpw)/VTIcw] and dimensionless index (DI) [VTIpw/VTIcw] were calculated. Corrected AVA was calculated by substituting MDCT LVOT area into CE. The majority (96%) of patients had eccentric LVOT. LVOT area, measured on MDCT, was higher than on TTE (3.84 ± 0.8 cm(2) versus 3.03 ± 0.5 cm(2), P<0.01). TTE-AVA was smaller than AVA(p) and corrected AVA (0.67 ± 0.1cm(2), 0.82 ± 0.3 cm(2), and 0.86 ± 0.3 cm(2), P<0.01). Using TTE measurements alone, 73% of patients had congruence for severe AS (DI ≤0.25 and CE AVA <0.8 cm(2)), which increased to 92% using corrected CE.
In patients with suspected severe AS, incorporation of MDCT-LVOT area into CE improves congruence for AS severity.
在主动脉瓣狭窄（AS）患者中，准确评估严重程度对于治疗决策至关重要。经胸超声心动图（TTE）连续方程（CE）估计主动脉瓣口面积（AVA）假设左心室流出道（LVOT）为圆形。我们评估了 3D 多排螺旋 CT（MDCT）对 AS 严重程度的 TTE 评估的增量效用。
我们纳入了 51 名接受治疗选择评估的有钙化性 AS 的患者（年龄 81±8 岁；61%为男性；平均梯度 42±12mmHg）。TTE 参数包括收缩期 LVOT 直径（D）和通过 LVOT 的连续和脉冲波（CW 和 PW）速度时间积分（VTI）以及平均跨主动脉梯度。MDCT 参数包括收缩期 LVOT 面积、最大与最小 LVOT 直径之比（偏心指数）和主动脉平面测量法（AVA(p)）。计算 TTE-CE AVA[（D(2)×0.786×PW-VTI）/VTIcw]和无量纲指数（DI）[PW-VTI/VTIcw]。通过将 MDCT LVOT 面积代入 CE 计算校正后的 AVA。大多数（96%）患者的 LVOT 呈偏心性。MDCT 测量的 LVOT 面积高于 TTE（3.84±0.8cm(2)比 3.03±0.5cm(2)，P<0.01）。TTE-AVA 小于 AVA(p)和校正后的 AVA（0.67±0.1cm(2)、0.82±0.3cm(2)和 0.86±0.3cm(2)，P<0.01）。单独使用 TTE 测量，73%的患者严重 AS 程度一致（DI≤0.25 和 CE AVA<0.8cm(2)），使用校正后的 CE 则增加到 92%。
在疑似严重 AS 的患者中，将 MDCT-LVOT 面积纳入 CE 可提高 AS 严重程度的一致性。
