Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec, Québec, Canada.
JACC Cardiovasc Imaging. 2011 Oct;4(10):1053-62. doi: 10.1016/j.jcmg.2011.06.021.
The objectives were to compare different Doppler echocardiographic methods for the measurement of prosthetic valve effective orifice area (EOA) following transcatheter aortic valve implantation (TAVI) and to determine the factors influencing the EOA of transcatheter balloon expandable valves.
Previous studies have used different methods for the measurement of the valve EOA following TAVI. Factors influencing the EOA of transcatheter valves are unknown.
A total of 122 patients underwent TAVI with the use of the Edwards-SAPIEN valve (Edwards Lifesciences, Irvine, California). The EOA was measured by transthoracic echocardiography at hospital discharge, 6 months and 1 year after TAVI with the use of 2 methods as described in previous studies. In Method #1 (EOA(1)), LVOT diameter (LVOTd) entered in the continuity equation was measured at the base of prosthesis cusps whereas, in Method #2 (EOA(2)), LVOTd was measured immediately proximal to the prosthesis stent.
The average EOA(2) (1.57 ± 0.41 cm(2)) was larger (p < 0.01) than the EOA(1) (1.21 ± 0.38 cm(2)). Accordingly, incidence of severe PPM (indexed EOA ≤0.65 cm(2)/m(2)) was 3-fold lower with the use of EOA(2) than with EOA(1) (9% vs. 33%; p < 0.001). Mean transprosthetic gradient correlated better (p = 0.03) with indexed EOA(2) (r = -0.70, p < 0.0001) than with indexed EOA(1) (r = -0.58, p < 0.0001). Intraobserver and interobserver variability were lower for EOA(2) compared to EOA(1) (intra: 5% vs. 7%, p = 0.06; inter: 6% vs. 14%; p < 0.001). Aortic annulus size was the sole independent determinant (p = 0.01) of prosthetic valve EOA(2). The average EOA varied from 1.37 ± 0.23 cm(2) for aortic annulus size <19 mm up to 1.90 ± 0.17 cm(2) for size >23 mm.
When estimating the EOA of Edwards-SAPIEN valves by Doppler-echocardiography, it is recommended to use the LVOT diameter and velocity measured immediately proximal to the stent. The main determinant of the EOA of transcatheter valves is the patient's annulus size and these valves provide excellent hemodynamics even in patients with a small aortic annulus.
比较经导管主动脉瓣植入术（TAVI）后测量人工瓣膜有效开口面积（EOA）的不同多普勒超声心动图方法，并确定影响经导管球囊扩张瓣膜 EOA 的因素。
以前的研究使用了不同的方法来测量 TAVI 后瓣膜的 EOA。影响经导管瓣膜 EOA 的因素尚不清楚。
共有 122 例患者接受了爱德华兹-SAPIEN 瓣膜（爱德华生命科学公司，加利福尼亚州欧文）的 TAVI。在 TAVI 后，通过使用两种方法（如先前研究所述）在出院时、6 个月和 1 年后经胸超声心动图测量 EOA。在方法#1（EOA(1)）中，LVOT 直径（LVOTd）在瓣叶基底部输入连续方程；而在方法#2（EOA(2)）中，LVOTd 在瓣膜支架的近端直接测量。
平均 EOA(2)（1.57±0.41cm2）较大（p<0.01），而 EOA(1)（1.21±0.38cm2）较小。因此，使用 EOA(2)的严重 PPM（指数化 EOA≤0.65cm2/m2）发生率（9%对 33%）比 EOA(1)低 3 倍（p<0.001）。跨瓣梯度与指数化 EOA(2)（r=-0.70，p<0.0001）的相关性优于指数化 EOA(1)（r=-0.58，p<0.0001）。与 EOA(1)相比，EOA(2)的观察者内和观察者间变异性较低（观察者内：5%对 7%，p=0.06；观察者间：6%对 14%，p<0.001）。主动脉瓣环大小是人工瓣膜 EOA(2)的唯一独立决定因素（p=0.01）。瓣环大小为 19mm 以下时平均 EOA 为 1.37±0.23cm2，瓣环大小为 23mm 以上时平均 EOA 为 1.90±0.17cm2。
在通过多普勒超声心动图估计 Edwards-SAPIEN 瓣膜的 EOA 时，建议使用支架近端直接测量的 LVOT 直径和速度。经导管瓣膜 EOA 的主要决定因素是患者的瓣环大小，即使在主动脉瓣环较小的患者中，这些瓣膜也能提供出色的血流动力学效果。
