Schmitz Lothar, Stiller Brigitte, Koch Heike, Koehne Petra, Lange Peter
Department of Pediatric Cardiology, Charité Medical Center, Humboldt-University, Augustenburger Platz 1, D-13353 Berlin, Germany.
Early Hum Dev. 2004 Feb;76(2):91-100. doi: 10.1016/j.earlhumdev.2003.11.002.
In very low birth weight neonates, a left-to-right shunt via persistent ductus arteriosus (PDA) may interact with diastolic left ventricular function, but specific changes of Doppler parameters have yet to be reported. In a serial transmitral Doppler study, we investigated the impact of a PDA on diastolic function parameters. Twenty-two patients with and without PDA were examined on day 3.8+/-1 and day 14+/-2 after birth. By the first examination, 13 out of 22 patients had a PDA; by the second examination, the number was still 8 out of 22. Peak early and atrial flow velocities (44.8+/-15 and 50.1+/-13 cm/s, respectively) were higher (p<0.05) for neonates with PDA compared to those with closed duct (30.9+/-6 and 34.2 cm/s, respectively). Isovolumic relaxation time (IVRT) was shorter in neonates with PDA (45+/-7 ms, N=21) compared to those with a closed duct (55.3+/-5 ms, N=23) (p<0.01). IVRT correlated inversely with cardiac index (R=-0.79, p<0.01). All observed changes reversed to the normal range after closure of the PDA. When premature infants with a PDA experience a preload challenge, early and atrial peak velocities increase and IVRT shortens significantly. This coincidence of elevated transvalvular pressure differences and decreased IVRT in neonates with immature diastolic function can best be explained as a result of left atrial pressure elevation. Consequently, pulmonary venous pressure must be elevated, with its inherent effect on pulmonary capillary physiology. Thus, the monitoring of left ventricular diastolic function adds significant information to the care of preterm infants with a PDA.
在极低出生体重的新生儿中，经动脉导管未闭（PDA）的左向右分流可能会影响左心室舒张功能，但多普勒参数的具体变化尚未见报道。在一项连续的经二尖瓣多普勒研究中，我们调查了PDA对舒张功能参数的影响。对22例有或无PDA的患者在出生后第3.8±1天和第14±2天进行了检查。首次检查时，22例患者中有13例存在PDA；第二次检查时，22例中仍有8例存在PDA。与动脉导管闭合的新生儿相比，有PDA的新生儿的早期峰值流速和心房流速（分别为44.8±15和50.1±13 cm/s）更高（p<0.05）（分别为30.9±6和34.2 cm/s）。与动脉导管闭合的新生儿（55.3±5 ms，N=23）相比，有PDA的新生儿的等容舒张时间（IVRT）更短（45±7 ms，N=21）（p<0.01）。IVRT与心脏指数呈负相关（R=-0.79，p<0.01）。PDA闭合后，所有观察到的变化均恢复到正常范围。当患有PDA的早产儿经历前负荷挑战时，早期和心房峰值流速增加，IVRT显著缩短。在舒张功能不成熟的新生儿中，跨瓣压差升高和IVRT降低的这种巧合，最好解释为左心房压力升高的结果。因此，肺静脉压力必然升高，对肺毛细血管生理有其内在影响。因此，对左心室舒张功能的监测为患有PDA的早产儿的护理增加了重要信息。
