Mechanical Forces Involved in Cardiac C-Looping

Abstract

Cardiac looping is a vital morphogenetic process that transforms the initially straight heart tube into a curved tube normally directed toward the right side of the embryo. We examined the role of biomechanical forces during the initial stages of looping, when the heart bends and rotates into a c-shaped tube (c-looping). C-looping consists of two primary deformation components: ventral bending and dextral (rightward) rotation (torsion). Embryonic chick hearts were subjected to mechanical and chemical perturbations, and the experiments were simulated using a computational model. The results suggest that bending is driven primarily by actin polymerization within the heart tube, while rotation is driven by external loads due to the splanchnopleure and omphalomesenteric veins. The results of this study may help investigators searching for the link between gene expression and the mechanical processes that drive looping.

Ontogenetic development of the helical heart: concepts and facts

“…During the process of cardiac looping, the initially straight embryonic heart tube becomes transformed into a loop with a helical configuration [12][13][14][15]. Thirdly, the process of cardiac looping is generally said to bring the subdivisions of the embryonic heart tube (common atrium, atrio-ventricular region, primitive left and right ventricles, outflow tract) and the vessel primordia approximately into their definitive www.elsevier.com/locate/ejcts European Journal of Cardio-thoracic Surgery 29S (2006) S69-S74 topographical relationship to each other [16][17][18][19][20][21][22]. One might therefore speculate that -if present in the embryonic heart loop -the primordia of the myocardial units of Torrent-Guasp's ventricular myocardial band model might also acquire the basic outline of their definitive spatial arrangement during the phase of cardiac looping.…”