Kozák-Bárány A, Jokinen E, Saraste M, Tuominen J, Välimäki I
Department of Pediatrics, University of Turku, Turku, Finland.
J Pediatr. 2001 Oct;139(4):539-45. doi: 10.1067/mpd.2001.118199.
We studied the left ventricular systolic and diastolic function in preterm infants during the first month of life in comparison with the respective patterns in term neonates.
Serial 2-dimensional/M-mode and Doppler transmitral flow velocity measurements were performed in 20 preterm (gestational age, 32 to 36 weeks) and 25 term infants between days 2 and 5 after birth and at age 1 month.
After birth, the early velocity, early integral, early filling fraction, early and atrial velocity ratios, and early and atrial integral ratios were lower in the preterm than in the term infants (P <.01). During the first 4 weeks of life, these values, the atrial velocity, and the atrial integral increased gradually, whereas the atrial filling fraction, diastolic filling time, and deceleration time of early diastolic filling decreased slightly with postnatal age (P <.01) in the preterm infants. At age 1 month their diastolic function reached the level of term infants with the exception of early and atrial integral ratios and atrial filling fraction. The measures of systolic performance were within normal range, but midwall fractional shortening at 2 to 5 days (P <.05), and fractional shortening area (P <.05), as well as midwall fractional shortening (P <.01) at 1 month of age, were slightly inferior in the preterm than in the term infants. During the first month the left ventricular mass and left ventricular mass/body surface area ratio increased more markedly in the preterm than term infants, significantly in both groups (P <.05).
The preterm diastolic patterns represent a transition between the patterns of the fetus and those of term neonates. These changes reflect an improvement in the left ventricular diastolic function, more markedly in relaxation than in compliance. The postnatal increase in the transmitral measures and left ventricular mass suggest marked myocardial adaptation to the extrauterine environment in the preterm infant already during the first month.
我们研究了早产儿出生后第一个月的左心室收缩和舒张功能，并与足月儿的相应模式进行比较。
对20例早产儿（胎龄32至36周）和25例足月儿在出生后第2至5天以及1月龄时进行了连续二维/M型和多普勒二尖瓣血流速度测量。
出生后，早产儿的早期速度、早期积分、早期充盈分数、早期与心房速度比值以及早期与心房积分比值均低于足月儿（P<.01）。在出生后的前4周，这些值、心房速度和心房积分逐渐增加，而早产儿的心房充盈分数、舒张期充盈时间和早期舒张期充盈减速时间随出生后年龄略有下降（P<.01）。在1月龄时，除早期与心房积分比值和心房充盈分数外，他们的舒张功能达到了足月儿的水平。收缩功能指标在正常范围内，但早产儿在2至5天时的中壁缩短分数（P<.05）、缩短分数面积（P<.05）以及1月龄时的中壁缩短分数（P<.01）略低于足月儿。在第一个月期间，早产儿的左心室质量和左心室质量/体表面积比值比足月儿增加更为明显，两组均有显著差异（P<.05）。
早产儿的舒张模式代表了胎儿模式与足月儿模式之间的过渡。这些变化反映了左心室舒张功能的改善，在舒张方面比顺应性方面更为明显。二尖瓣测量值和左心室质量在出生后的增加表明，早产儿在出生后的第一个月内心肌已对宫外环境有明显适应。
