Department of Cardiothoracic Anaesthesiology, Copenhagen University Hospital, Blegdamsvej 9, Rigshospitalet, 2100, Copenhagen, Denmark.
Department of Cardiothoracic Surgery, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
J Clin Monit Comput. 2020 Dec;34(6):1139-1148. doi: 10.1007/s10877-020-00466-2. Epub 2020 Jan 25.
Right Ventricular (RV) output mostly derives from longitudinal shortening in normal hearts. However, following even uncomplicated cardiac surgery with preserved RV function a significant and sustained decrease in longitudinal contraction has been observed. How the RV compensates and sustains output in this setting remains unsettled. The aim of this study was to evaluate the RV contraction pattern by speckle tracking echocardiography to elucidate possible compensatory mechanisms mitigating the reduced RV longitudinal contraction after cardiac surgery. Thirty patients with normal preoperative ejection fraction and no valvulopathy underwent coronary artery bypass grafting (CABG) with the use of cardiopulmonary bypass (CPB). RV dedicated speckle tracking software measuring longitudinal and transverse displacement, as well as strain, was employed on transesophageal echocardiographic (TEE) images as part of the Right Ventricular Echocardiography in cardiac SurgEry (ReVERSE) study. Data was recorded at baseline (after anesthesia induction), immediately after CPB and upon chest closure. Tricuspid Annulus Plane Systolic Excursion (TAPSE) was reduced from 2.0 [1.6-2.5 cm] to 0.8 [0.6-11 mm] from baseline to after chest closure. RV longitudinal displacement was reduced from 6.1 [3.4-8.8 mm] to 2.9 [0.4-5.4 mm] at the same time-points. RV speckle tracking revealed concomitantly that transverse displacement of the free wall increased significantly from 1.2 [0-2.7 mm] at baseline to 5.4 [3.6-7.2 mm] after chest closure. RV speckle tracking strain did not change significantly. Increased transverse displacement likely compensates for reduction in RV longitudinal contraction following cardiac surgery and maintains cardiac output. The sustained output from the right ventricle was not related to an increased contractility.
右心室(RV)的输出主要来源于正常心脏的纵向缩短。然而,即使是心脏手术后 RV 功能正常的情况下,也观察到纵向收缩明显且持续下降。在这种情况下,RV 如何代偿并维持输出仍未得到解决。本研究旨在通过斑点追踪超声心动图评估 RV 收缩模式,以阐明可能的代偿机制,减轻心脏手术后 RV 纵向收缩减少。30 例术前射血分数正常且无瓣膜病的患者接受了冠状动脉旁路移植术(CABG),并使用体外循环(CPB)。RV 专用斑点追踪软件测量了经食管超声心动图(TEE)图像上的纵向和横向位移以及应变,作为心脏手术中的右心室超声心动图(ReVERSE)研究的一部分。数据记录在基线(麻醉诱导后)、CPB 后立即和胸部关闭时。三尖瓣环平面收缩期位移(TAPSE)从基线时的 2.0 [1.6-2.5cm]降至胸部关闭时的 0.8 [0.6-11mm]。同时,RV 纵向位移从 6.1 [3.4-8.8mm]降至 2.9 [0.4-5.4mm]。RV 斑点追踪显示,在同一时间点,游离壁的横向位移从基线时的 1.2 [0-2.7mm]显著增加至胸部关闭时的 5.4 [3.6-7.2mm]。RV 斑点追踪应变没有明显变化。RV 纵向收缩减少后,横向位移的增加可能补偿了 RV 的收缩,维持了心输出量。右心室持续的输出与收缩力的增加无关。