Fenster Brett E, Browning James, Schroeder Joyce D, Schafer Michal, Podgorski Chris A, Smyser Jamie, Silveira Lori J, Buckner J Kern, Hertzberg Jean R
Division of Cardiology, National Jewish Health, Denver, Colorado;
Department of Mechanical Engineering, University of Colorado, Boulder, Colorado;
Am J Physiol Heart Circ Physiol. 2015 Sep 15;309(6):H1087-93. doi: 10.1152/ajpheart.00278.2015. Epub 2015 Aug 7.
Right ventricular diastolic dysfunction (RVDD) is an important prognostic indicator in pulmonary arterial hypertension (PAH). RV vortex rings have been observed in healthy subjects, but their significance in RVDD is unknown. Vorticity, the local spinning motion of an element of fluid, may be a sensitive measure of RV vortex dynamics. Using four-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we investigated the relationship between right heart vorticity with echocardiographic indexes of RVDD. Thirteen (13) PAH subjects and 10 controls underwent same-day 4D flow CMR and echocardiography. RV diastolic function was assessed using trans-tricuspid valve (TV) early (E) and late (A) velocities, E/A ratio, and e' and a' tissue Doppler velocities. RV and right atrial (RA) integrated mean vorticity was calculated for E and A-wave filling periods using 4D datasets. Compared with controls, A-wave vorticity was significantly increased in RVDD subjects in both the RV [2343 (1,559-3,295) vs. 492 (267-2,649) 1/s, P = 0.028] and RA [30 (27-44) vs. 9 (5-27) 1/s, P = 0.005]. RA E vorticity was significantly decreased [13 (7-22) vs. 28 (15-31) 1/s, P = 0.038] in RVDD. E-wave vorticity correlated TV e', E-,and TV E/A (P < 0.05), and A-wave vorticity associated with both TV A and E/A (P < 0.02). RVDD is associated with alterations in E- and A-wave vorticity, and vorticity correlates with multiple echocardiographic markers of RVDD. Vorticity may be a robust noninvasive research tool for the investigation of RV fluid and tissue mechanical interactions in PAH.
右心室舒张功能障碍（RVDD）是肺动脉高压（PAH）的一项重要预后指标。在健康受试者中已观察到右心室涡环，但其在RVDD中的意义尚不清楚。涡度，即流体元素的局部旋转运动，可能是右心室涡动力学的一个敏感指标。利用四维（4D）流动心脏磁共振成像（CMR），我们研究了右心涡度与RVDD超声心动图指标之间的关系。13例PAH患者和10名对照者在同一天接受了4D流动CMR和超声心动图检查。使用经三尖瓣（TV）早期（E）和晚期（A）速度、E/A比值以及e'和a'组织多普勒速度评估右心室舒张功能。利用4D数据集计算E波和A波充盈期的右心室和右心房（RA）综合平均涡度。与对照组相比，RVDD患者的右心室和RA中A波涡度均显著增加[分别为2343（1559 - 3295）与492（267 - 2649）1/s，P = 0.028]和[30（27 - 44）与9（5 - 27）1/s，P = 0.005]。RVDD患者的RA E波涡度显著降低[13（7 - 22）与28（15 - 31）1/s，P = 0.038]。E波涡度与TV e'、E以及TV E/A相关（P < 0.05），A波涡度与TV A和E/A均相关（P < 0.02）。RVDD与E波和A波涡度改变相关，且涡度与RVDD的多个超声心动图标志物相关。涡度可能是用于研究PAH中右心室流体与组织机械相互作用的一种强大的非侵入性研究工具。
