Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota.
Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota; Division of Cardiology, Department of Internal Medicine, Chung-Ang University Hospital, Seoul, Korea.
J Am Soc Echocardiogr. 2015 Jul;28(7):780-5. doi: 10.1016/j.echo.2015.02.016. Epub 2015 Apr 6.
Although the highest aortic valve velocity was thought to be obtained from imaging windows other than the apex in about 20% of patients with severe aortic stenosis (AS), its occurrence appears to be increasing as the age of patients has increased with the application of transcatheter aortic valve replacement. The aim of this study was to determine the frequency with which the highest peak jet velocity (Vmax) is found at each imaging window, the degree to which neglecting nonapical imaging windows underestimates AS severity, and factors influencing the location of the optimal imaging window in contemporary patients.
Echocardiograms obtained in 100 consecutive patients with severe AS from January 3 to May 23, 2012, in which all imaging windows were interrogated, were retrospectively analyzed. AS severity (aortic valve area and mean gradient) was calculated on the basis of the apical imaging window alone and the imaging window with the highest peak jet velocity. The left ventricular-aortic root angle measured in the parasternal long-axis view as well as clinical variables were correlated with the location of highest peak jet velocity.
Vmax was most frequently obtained in the right parasternal window (50%), followed by the apex (39%). Subjects with acute angulation more commonly had Vmax at the right parasternal window (65% vs 43%, P = .05) and less commonly had Vmax at the apical window (19% vs 48%, P = .005), but Vmax was still located outside the apical imaging window in 52% of patients with obtuse aortic root angles. If nonapical windows were neglected, 8% of patients (eight of 100) were misclassified from high-gradient severe AS to low-gradient severe AS, and another 15% (15 of 100) with severe AS (aortic valve area < 1.0 cm(2)) were misclassified as having moderate AS (aortic valve area > 1.0 cm(2)).
In this contemporary cohort, Vmax was located outside the apical imaging window in 61% of patients, and neglecting the nonapical imaging windows resulted in the misclassification of AS severity in 23% of patients. Aortic root angulation as measured by two-dimensional echocardiography influences the location of Vmax modestly. Despite increasing time constraints on many echocardiography laboratories, these data confirm that routine Doppler interrogation from multiple imaging windows is critical to accurately determine the severity of AS in contemporary clinical practice.
尽管在约 20%的严重主动脉瓣狭窄（AS）患者中，最高主动脉瓣速度被认为可以通过心尖以外的成像窗获得，但随着经导管主动脉瓣置换术的应用，患者年龄的增加，这种情况似乎越来越常见。本研究的目的是确定每个成像窗中最高峰值射流速度（Vmax）的出现频率，忽略非心尖成像窗对 AS 严重程度的低估程度，以及影响当代患者最佳成像窗位置的因素。
回顾性分析了 2012 年 1 月 3 日至 5 月 23 日连续 100 例接受重度 AS 治疗的患者的超声心动图，这些患者的所有成像窗均进行了检查。仅根据心尖成像窗和最高峰值射流速度的成像窗计算 AS 严重程度（主动脉瓣面积和平均梯度）。胸骨旁长轴视图中测量的左心室-主动脉根部角度以及临床变量与最高峰值射流速度的位置相关。
Vmax 最常出现在右胸骨旁窗（50%），其次是心尖（39%）。锐角患者更常在心尖右侧窗获得 Vmax（65%比 43%，P=.05），而较少在心尖窗获得 Vmax（19%比 48%，P=.005），但在钝角主动脉根部的患者中，Vmax 仍位于心尖成像窗之外，占 52%。如果忽略非心尖窗口，8%（8/100）的患者会从高梯度重度 AS 错误分类为低梯度重度 AS，另外 15%（15/100）的重度 AS（主动脉瓣面积<1.0cm²）患者会错误分类为中度 AS（主动脉瓣面积>1.0cm²）。
在这个当代队列中，61%的患者 Vmax 位于心尖成像窗之外，如果忽略非心尖成像窗，23%的患者会错误分类为 AS 严重程度。二维超声心动图测量的主动脉根部角度对 Vmax 的位置有一定影响。尽管许多超声心动图实验室的时间限制越来越大，但这些数据证实，常规从多个成像窗进行多普勒检查对于准确确定当代临床实践中 AS 的严重程度至关重要。
