THE ROLE OF THE THEBESIAN VESSELS IN THE CIRCULATION OF THE HEART.

In summary, evidence has been presented to show a direct connection other than through the capillaries between the coronary arteries and the chambers of the heart. This connection was shown by perfusion, injections and serial sections to be through the Thebesian veins. Communications between the larger coronary veins and the Thebesian veins were also demonstrated by the same methods. Serial sections through Thebesian veins have shown capillaries draining directly into them. Under certain conditions it has been shown that as much as 90 per cent of the arterial flow may escape via the Thebesian vessels. Lastly, in the event of gradual closure of the orifices of the coronary arteries, the Thebesian vessels can supply the heart muscle with sufficient blood to enable it to maintain an efficient circulation.