Cardiomyopathie hypertrophique

Hypokinetic Hypertrophic Cardiomyopathy: A Rare Case of a Spontaneously Regressive Form in a Newborn

Hypertrophic cardiomyopathy (HCM) of the newborn is a rare condition, characterized by great clinical variability, with a relative paucity of data on the pediatric population, especially newborns. Early diagnosis can have an impact on the patient's life course and prevent progression to sudden death. In this article, we report the case of a newborn admitted with late-onset neonatal respiratory distress, complicated by heart failure. The newborn was matured by two antenatal injections of betamethasone, which were received as part of a threat of premature delivery. Echocardiography revealed hypokinetic HCM. The rapidity of the establishment of the diagnosis contributed to the patient's survival and improvement within a few weeks under well-managed medical treatment. A complete workup was conducted, with negative results. The most suggested explanation for this condition was the use of antenatal corticosteroids.

New insights into the assessment of the prosthetic valve performance in the presence of subaortic stenosis through a fluid-structure interaction model

The aim of this study was to contribute to improving the accuracy of clinical assessments of valve performance in situations involving the concomitant presence of a prosthetic valve and subaortic stenosis (SAS). Physiological flow in a two-dimensional model for a bileaflet mechanical heart valve was investigated numerically in terms of the fluid-structure interactions. The fluid dynamics in a model with SAS of the left ventricle outflow tract were compared with those given by a healthy model. The results show that in the model with SAS, one leaflet did not close during the observed systolic phase, whereas the other one showed similar behaviour to that of the leaflet in the healthy model. In addition, the main flow did not occur along the central axis and a deviated jet was set up between leaflets, contrary to what occurred in the model without SAS. Current clinical diagnostic indices, which are mainly based on the central jet flow velocities, are therefore unsuitable for use in this pathological situation and should be used with great caution.