Abnormal ventricular looping and abnormal laterality of the atrial chambers are the main morphogenetic mechanisms of cardiac lesions in cultured rat embryos treated with retinoic acid

An integrative multiscale view of early cardiac looping

The heart is the first organ to form and function during the development of an embryo. Heart development consists of a series of events believed to be highly conserved in vertebrates. Development of heart begins with the formation of the cardiac fields followed by a linear heart tube formation. The straight heart tube then undergoes a ventral bending prior to further bending and helical torsion to form a looped heart. The looping phase is then followed by ballooning, septation, and valve formation giving rise to a four-chambered heart in avians and mammals. The looping phase plays a central role in heart development. Successful looping is essential for proper alignment of the future cardiac chambers and tracts. As aberrant looping results in various congenital heart diseases, the mechanisms of cardiac looping have been studied for several decades by various disciplines. Many groups have studied anatomy, biology, genetics, and mechanical processes during heart looping, and have proposed multiple mechanisms. Computational modeling approaches have been utilized to examine the proposed mechanisms of the looping process. Still, the exact underlying mechanism(s) controlling the looping phase remain poorly understood. Although further experimental measurements are obviously still required, the need for more integrative computational modeling approaches is also apparent in order to make sense of the vast amount of experimental data and the complexity of multiscale developmental systems. Indeed, there needs to be an iterative interaction between experimentation and modeling in order to properly find the gap in the existing data and to validate proposed hypotheses. This article is categorized under: Cardiovascular Diseases > Genetics/Genomics/Epigenetics Cardiovascular Diseases > Computational Models Cardiovascular Diseases > Molecular and Cellular Physiology.

Diagnosis and management of pheochromocytoma during pregnancy

Although the presence of pheochromocytoma in pregnancy is extremely rare, this association deserves much attention as the tumor constitutes a very high risk for both mother and fetus. Any pregnant woman with hypertension, especially if paroxysmal or labile, or with so far unexplained "spells", should induce the clinician to consider the possibility of a pheochromocytoma. Maternal and fetal survival depend a lot on an early diagnosis, a correct medical therapy and a correct timing of delivery and surgery. In this respect, a strict collaboration between obstetricians, endocrinologists, anesthesiologists and surgeons is pivotal.