Nifedipine disturbs fetal cardiac function during hypoxemia in a chronic sheep model at near term gestation

BackgroundNifedipine is a widely used drug in pregnancies complicated by maternal hypertensive disorders that can be associated with placental insufficiency and fetal hypoxemia. The evidence regarding myocardial responses to nifedipine hypoxemia limited.ObjectiveWe hypothesized would not impair sheep cardiac function under hypoxemic environment. In particular, we investigated the effects of on ventricular functional parameters output.Study DesignA total 21 chronically instrumented at 122 134 gestational days (term, 145 days) were included this study. Fetal was evaluated measuring global longitudinal strain, indices describing systolic diastolic function, outputs using two-dimensional speckle tracking tissue spectral pulsed-wave Doppler echocardiography. carotid artery blood pressure gas values invasively monitored. After baseline data collection, induced hyperoxygenation. phase 9 fetuses received infusion, 12 saline infusion. Data collected 30 120 minutes after infusion started. oxygenation normalized, normoxemia collected, while continued.ResultsHypoxemia decreased mean arterial from 40 (8) mm Hg 35 (P<.007), left strain showed less deformation than (P=.001). Under hypoxemia, caused reduction right (P<.05), decrease isovolumic relaxation velocity its deceleration (P<.01) indicating dysfunction, drop output (P<.05). Nifedipine did alter or output. When restored, returned level.ConclusionIn fetus, impaired reduced detrimental abolished, when restored. Our findings suggest environment triggers function. limited. We A continued. Hypoxemia level.