Mesa A, Jessurun C, Hernandez A, Adam K, Brown D, Vaughn W K, Wilansky S
Department of Cardiology, St Luke's Episcopal Hospital and Baylor College of Medicine, Texas Heart Institute, Houston, USA.
Circulation. 1999 Feb 2;99(4):511-7. doi: 10.1161/01.cir.99.4.511.
Little information is available about changes in left ventricular diastolic function during pregnancy. We used mitral inflow and pulmonary venous flow profiles to evaluate left ventricular diastolic function in 37 healthy pregnant women 26 to 41 years old (mean, 32 years).
Echocardiographic studies were performed at the end of each trimester. Eight subjects (control group) underwent similar testing 1 to 3.5 months (mean, 1.7 months) postpartum. During pregnancy, the cardiac output increased significantly as a result of an increased heart rate and, to a lesser degree, stroke volume. Significantly decreased systemic vascular resistance and increased left ventricular mass were also noted. Peak mitral flow velocity in early diastole (E) increased 13. 3% during the first trimester and remained at the high end of normal throughout pregnancy. Peak A-wave velocity (A) increased maximally in the third trimester. Compared with control subjects, first-trimester subjects had a significantly increased E/A ratio. The ratio subsequently decreased, reflecting the augmented A-wave velocity. Pulmonary venous peak systolic forward flow velocity increased, peaking in the second trimester (nonsignificant), but returned to baseline levels postpartum. The pulmonary venous diastolic time-velocity integral decreased significantly from the first to the third trimester. Peak pulmonary venous reverse flow velocity at atrial contraction increased significantly, without being markedly changed in duration.
Pregnancy, a chronic, natural volume-overload state, has important effects on hemodynamic and echocardiographic variables. Based on pulmonary venous flow and left ventricular inflow velocities, our results provide a standard reference concerning diastolic filling dynamics by trimester.
关于孕期左心室舒张功能变化的信息较少。我们利用二尖瓣血流和肺静脉血流频谱，对37名年龄在26至41岁（平均32岁）的健康孕妇的左心室舒张功能进行了评估。
在妊娠各期结束时进行超声心动图检查。8名受试者（对照组）在产后1至3.5个月（平均1.7个月）接受了类似检查。孕期，由于心率增加以及程度较轻的每搏输出量增加，心输出量显著增加。还观察到全身血管阻力显著降低和左心室质量增加。舒张早期二尖瓣血流峰值速度（E）在孕早期增加了13.3%，并在整个孕期保持在正常范围的上限。A波峰值速度（A）在孕晚期增加最多。与对照组相比，孕早期受试者的E/A比值显著增加。该比值随后下降，反映了A波速度的增加。肺静脉收缩期正向血流峰值速度增加，在孕中期达到峰值（无统计学意义），但产后恢复到基线水平。肺静脉舒张期时间速度积分从孕早期到孕晚期显著降低。心房收缩时肺静脉反向血流峰值速度显著增加，持续时间无明显变化。
妊娠是一种慢性自然容量超负荷状态，对血流动力学和超声心动图变量有重要影响。基于肺静脉血流和左心室流入速度，我们的结果提供了各孕期舒张期充盈动力学的标准参考。
