Video-imaging assessment of initial beating patterns of the early embryonic chick heart.

The spatiotemporal pattern and its developmental changes were assessed of the beating of the early embryonic chick tubular heart at the 9- to 17-somite stages of development using a video-imaging method together with the three-dimensional modeling. In the late 9- and early 10-somite stages, contractions were observed only at the right margin of the ventricular wall. As development proceeded to 12-somite or later stages, the propagation of contractile waves from the atrial pacemaking area towards the root of the ventral aortae was observed. The prototype of the peristaltic pattern of contractions was established by the 14-somite stage of development with an increase in the conduction velocity of the contractile wave.