From the Department of Anaesthesia and Acute Pain Medicine, St. Vincent's Hospital Melbourne, Fitzroy, Victoria, Australia (BC, CB, RK).
Eur J Anaesthesiol. 2021 Dec 1;38(12):1253-1261. doi: 10.1097/EJA.0000000000001499.
Assessment of left ventricular outflow tract (LVOT) area is a key component of quantification of aortic stenosis and stroke volume. Current international guidelines recommend measurement of the LVOT diameter with two-dimensional (2D) echocardiography and assume a circle. This may lead to erroneous measures of aortic valve area and adversely affect peri-operative decision making. Multiplane orthogonal (biplane) and three-dimensional (3D) echocardiography imaging may allow more accurate calculation of LVOT, aortic valve area and stroke volume.
To evaluate the shape and area of the LVOT with conventional 2D diameter, short axis cross-sectional planimetry with biplane imaging and 3D multiplane reconstruction in patients undergoing cardiac surgery with transoesophageal echocardiography (TOE).
A retrospective observational study.
A single centre university hospital.
119 patients undergoing cardiac surgery with TOE.
None.
Measurements of the shape and area of the LVOT with standard 2D TOE, short axis biplane imaging and 3D TOE.
The LVOT shape is elliptical in 70% of patients. The (mean ± SD, [range]) LVOT cross-sectional area with 2D TOE was 4.29 cm2 ± 0.98, [2.46 to 6.70], with biplane was 4.68 cm2 ± 1.03, [2.92 to 7.30] and with 3D was 4.59 cm2 ± 0.99, [2.78 to 7.10]. There was a statistically significant difference (P < 0.001) in the three pairwise comparisons. 2D LVOT area had large bias (7 to 9%) and wider limits of agreement (LOA) with both biplane and 3D LVOT area (-17 to 36%). Biplane and 3D LVOT areas had small bias (1.8%) with relatively narrow LOA (-8 to 11%).
2D diameter measures of the LVOT assuming a circle underestimate LVOT area, underestimate aortic valve area and increase the apparent severity of aortic stenosis. This may lead to inappropriate aortic valve intervention. In a busy operating room environment, we suggest that for the calculation of stroke volume and aortic valve area, LVOT area is measured with biplane imaging.
Observational study with no interventions so trial not registered.
评估左心室流出道（LVOT）面积是主动脉瓣狭窄和心排量定量评估的关键组成部分。目前的国际指南建议使用二维（2D）超声心动图测量 LVOT 直径，并假设为圆形。这可能导致主动脉瓣面积的错误测量，并对围手术期决策产生不利影响。多平面正交（双平面）和三维（3D）超声心动图成像可能允许更准确地计算 LVOT、主动脉瓣面积和心排量。
在接受经食管超声心动图（TOE）检查的心脏手术患者中，评估常规 2D 直径、双平面成像短轴横截面平面测量和 3D 多平面重建的 LVOT 形状和面积。
回顾性观察性研究。
单中心大学医院。
119 例行心脏手术并接受 TOE 检查的患者。
无。
标准 2D TOE、短轴双平面成像和 3D TOE 测量 LVOT 的形状和面积。
70%的患者 LVOT 呈椭圆形。2D TOE 的 LVOT 横截面积为 4.29cm2±0.98[2.46 至 6.70]，双平面为 4.68cm2±1.03[2.92 至 7.30]，3D 为 4.59cm2±0.99[2.78 至 7.10]。这三种两两比较之间存在统计学显著差异（P<0.001）。2D LVOT 面积的偏差较大（7%至 9%），与双平面和 3D LVOT 面积的一致性限（LOA）较宽（-17 至 36%）。双平面和 3D LVOT 面积的偏差较小（1.8%），相对 LOA 较窄（-8 至 11%）。
假设圆形的 2D 直径测量法低估了 LVOT 面积，低估了主动脉瓣面积，并增加了主动脉瓣狭窄的表观严重程度。这可能导致主动脉瓣干预不当。在繁忙的手术室环境中，我们建议使用双平面成像测量 LVOT 面积来计算心排量和主动脉瓣面积。
无干预的观察性研究，因此未注册试验。
