Ventricular wall thickness in the fetal dog.

Ventricular wall thickness of 21 50-to 60-day canine fetuses was determined by direct measurement with calipers. Measurements were made of the left and right ventricular walls and of the interventricular septum, perpendicular to the apico-basilar axis at the location just below the aortic valve, and midway between the coronary sulcus and the apex. Mean determiniations were used to characterize the wall thickne-s at the various levels. The right wall was found to be thickpreciable thickness differences between the septal and left wall at this location. At the level of the midventricular wall, the septal wall thickness exceeded that of the left and right wall. Left and right wall thickness at this level were similar.