THE EXTENT OF THE CAPILLARY BED OF THE HEART

TLDR

The authors used coronary artery injections into beating hearts to map capillary distribution in normal and pathological hearts, enabling quantification of capillaries and assessment of blood supply to muscle, valves, and aortic wall. The study found a dense capillary network with roughly one capillary per muscle fibre in ventricular walls and papillary muscles—about twice the density seen in skeletal muscle—while auricular muscle, Purkinje system, and valves had fewer capillaries.

Abstract

By means of injections made into the coronary arteries of beating hearts it has been possible to determine the number of capillaries in the normal heart muscle. This study has shown a very rich blood supply with an average of approximately one capillary for each muscle fibre in the ventricular walls and papillary muscles, and a less abundant supply in the auricular muscle and Purkinje system. The number of capillaries per sq. mm. of ventricular wall or papillary muscle is about twice that found by Krogh in skeletal muscle. Capillaries were not found constantly in the valves of hearts in which there was apparently a complete injection of the capillary bed. The method described for injecting the capillaries of the heart also provides a means of studying the blood supply to the muscle, valves and aortic wall in pathological hearts.