High-frequency ultrasound assessment of the murine heart from embryo through to juvenile.
Niamh Corrigan, Derek P Brazil, Fionnuala M AuliffeReproductive sciences (Thousand Oaks, Calif.)2010
AIM: The aim of this study is to assess the murine heart of normal embryos, neonates, and juveniles using high-frequency ultrasound. METHODS: Diastolic function was measured with E/A ratio (E wave velocity/A wave velocity) and isovolumetric relaxation time (IRT), systolic function with isovolumetric contraction time (ICT), percentage fractional shortening (FS %), percentage ejection fraction (EF %). Global cardiac performance was quantified using myocardial performance index (MPI). RESULTS: Isovolumetric relaxation time remained stable from E10.5 to 3 weeks. Systolic function (ICT) improved with gestation and remained stable from E18.5 onward. Myocardial performance index showed improvement in embryonic life (0.82- 0.63) and then stabilized from 1 to 3 week (0.60-0.58). Percentage ejection fraction remained high during gestation (77%-69%) and then decreased from the neonate to juvenile (68%-51%). CONCLUSION: The ultrasound biomicroscope allows for noninvasive in-depth assessment of cardiac function of embryos and pups. Detailed physiological and functional cardiac function readouts can be obtained, which is invaluable for comparison to mouse models of disease.