Heart ultrasound in prenatal surgery for fetal well-being : the myelomeningocele lamb model

Background: prenatal surgery to correct congenital malformations is a stressful event which may lead to cardiovascular derangements and influences fetal well-being and growth. Intrauterine cardiac monitoring is necessary to assess the adaptative response during invasive procedures. Data on heart sonographic appearance in a fetal lamb model of myelomeningocele (MMC), an useful tool for translational research in human pathologies, are presented. Methods: at MMC induction (T1, 75 days' gestation) and at surgical repair of the defect (T2, 110 days' gestation), preoperative fetal echocardiography was performed. An ultrasound system (Aloka-prosound- α6) equipped with doppler mode, linear and convex array transducer was used. Results: sonographic data were collected in all fetuses and at both surgical time points. Gain in cardiac size was measured in fetuses undergoing surgery. No significant difference in cardiac measurements between treated and control fetuses was noted. The two ventricules resulted equal in size at T1, while at T2 right ventricle prevalence was observed. Conclusion: preliminary fetal echocardiographic data of in the MMC-lamb model are presented for the first time. Adequate surveillance during stressful interventions should help maintain regular gain in heart size and fetal well-being particularly during invasive surgery.