Papadopoulou Elektra, Kaladaridou Anna, Agrios John, Matthaiou John, Pamboukas Constantinos, Toumanidis Savvas
Department of Clinical Therapeutics, Medical School, "Alexandra" Hospital, University of Athens, Athens, Greece.
Echocardiography. 2014 Feb;31(2):155-63. doi: 10.1111/echo.12345. Epub 2013 Sep 13.
During pregnancy, important hemodynamic changes occur, consistent with an increase in preload and decrease in afterload and systemic vascular resistance. The aim of the present study was to investigate the changes in left ventricular (LV) strain and rotational properties during the 3 trimesters of normal pregnancy and to examine the factors that drive these changes.
Twenty-seven pregnant women (29.7 ± 6.9 years) and 11 age-matched nonpregnant controls (29.9 ± 5.4 years) were evaluated. Conventional echocardiography and two-dimensional speckle tracking imaging were performed at 8-12 (1st trimester), 21-28 (2nd trimester), and 33-36 (3rd trimester) weeks of pregnancy. LV rotation, twist, untwisting rate, and circumferential strain were measured using the parasternal short-axis views at basal and apical levels. Global longitudinal strain was calculated from the LV apical views. Peak LV twist and peak untwisting rate increased significantly in the 3rd trimester of normal pregnancy (13.48 ± 2.90°, 13.12 ± 3.30°, 16.83 ± 3.61°, P < 0.001; and -111.52 ± 23.54°/sec, -107.40 ± 26.58°/sec, -144.30 ± 45.14°/sec, P < 0.001; in the 1st, 2nd, and 3rd trimester, respectively). Global longitudinal and circumferential strain of the apex decreased significantly from the 2nd trimester. An independent association was found between the change in LV twist and the change in LV end-systolic volume between the 1st and 3rd trimester. Peak untwisting rate at the 3rd trimester correlated significantly with peak twist and LV end-diastolic volume.
During normal pregnancy, LV twist and peak untwisting rate increase in the 3rd trimester and correlate with end-systolic and end-diastolic volume, respectively. Circumferential strain of the apex and global longitudinal strain decrease from the 2nd trimester.
在孕期会发生重要的血流动力学变化，表现为前负荷增加、后负荷及全身血管阻力降低。本研究旨在调查正常孕期三个阶段左心室（LV）应变及旋转特性的变化，并探究驱动这些变化的因素。
对27名孕妇（29.7±6.9岁）和11名年龄匹配的非孕对照者（29.9±5.4岁）进行评估。在妊娠8 - 12周（孕早期）、21 - 28周（孕中期）和33 - 36周（孕晚期）进行常规超声心动图检查及二维斑点追踪成像。使用胸骨旁短轴切面在心底和心尖水平测量左心室旋转、扭转、解旋速率及圆周应变。从左心室心尖切面计算整体纵向应变。正常孕期晚期左心室峰值扭转和峰值解旋速率显著增加（分别为13.48±2.90°、13.12±3.30°、16.83±3.61°，P<0.001；以及-111.52±23.54°/秒、-107.40±26.58°/秒、-144.30±45.14°/秒，P<0.001，分别对应孕早期、孕中期和孕晚期）。心尖的整体纵向和圆周应变从孕中期开始显著降低。发现孕早期和孕晚期之间左心室扭转变化与左心室收缩末期容积变化之间存在独立关联。孕晚期的峰值解旋速率与峰值扭转及左心室舒张末期容积显著相关。
在正常孕期，左心室扭转和峰值解旋速率在孕晚期增加，分别与收缩末期和舒张末期容积相关。心尖的圆周应变和整体纵向应变从孕中期开始降低。
