Microvascular architecture of the rabbit ventricular walls: a scanning electron microscopic study of corrosion casts.

Microvascular architecture of the rabbit heart was studied with scanning electron microscopy of corrosion casts. Arterioles divide into several finer branches and form a capillary plexus. Capillaries of the plexus run generally in parallel with cardiac muscle fibers and converge into venules and veins. Most of the veins run towards the epicardium, while some of them run towards the endocardium. The subendocardial veins sometimes open into the right ventricular cavity. Arterial branches of the right ventricular free wall and the right ventricular side of the septum open into the ventricular cavity. Arteriovenous anastomoses are observed in the left ventricular free wall and in the right ventricular side of the septum.