An x-ray microscopic study of the arterial supply to the conducting system of the human heart.

Abstract

may be mentioned. More recently Carbonell (1956) isolated the conducting system of the heart by demonstrating the activity of esterases with histochemical techniques, and Lev, Benjamin, and White (1958) reported a histopathological study on the conducting system in a heart with complete block of 42 years' duration. Titus, Neufeld, and Edwards (1964) reported on three cases in which the pulmonary trunk and ascending aorta originated from the right ventricle and showed that the conducting system had been displaced dorsally.Little reference, however, could be found in the reports to the pattern and distribution of arterioles and capillaries in the conducting system of the human heart. Schlesinger (1938) and Fulton (1963) demonstrated the distribution of the coronary arteries in man after the injection of radioopaque media, but the resolution of the x-ray technique did not allow the visualization of capillaries, and no mention is made of any special distribution of vessels to the conducting system. The pattern of blood supply to the sinu-atrial node in the dog has been described as coming from the right coronary artery (Meek, Keenan, and Theisen, 1929;Moore, 1930; Pianetto, 1939;Kazzaz and Shanklin, 1950), and Halpern (1954) described additional branches being distributed to the node from the left coronary artery and right internal mammary artery. In man, Last (1963) states, without further amplification, that the sinu-atrial node is supplied by a branch of the right coronary artery in 60 per cent of cases, and that the atrio-ventricular node and bundle of His are supplied by a branch of the left coronary artery in 90 per cent.This work presents an account of the pre-capillary arteriole and capillary pattern of distribution in the sinu-atrial node and atrio-ventricular conducting system of the human heart, using the Coslett Nixon X-Ray Projection Microscope. This gives an opportunity for investigating unfixed, fullthickness preparations without histological intervention, in contrast to the routine staining, injection, and clearing techniques for examining capillary beds by previous

Surgical pathology of the conducting system of the heart.

“…The right circumflex artery thus supplies the S-A node in 55 per cent, and the A-V node in 90 per cent of hearts, and could more reasonably be called the " artery of sudden death " than the anterior descending artery (James, 1965). An injection x-ray microscopic study by Clarke (1965) showed that capillary densities were greatest in the two nodes.…”

Histocompatibility Studies in a Closely Bred Colony of Dogs

“…Such lesions include endothelial edema and perivascular mononuclear cell infiltrates in the atrioventricular node, conduction bundles, and bundle branches (35,53,54). A possible explanation for this finding is suggested by Clarke's demonstration of the particularly rich vascularity of the sinus node, atrioventicular node, and main conducting bundles (55).…”

Lymph drainage of sinu-atrial node in man and dog

“…The papers dealing with the cardiac conduction system are chiefly concerned with the question o f its structure and blood supply [Keith and Flack, 1907;H aas, 1911: T ruex and Schwartz, 1951: Halpern, 1954L umb el at., 1959L umb el at., : James, 1962L umb el at., , 1970A braham, 1964;Clarke, 1965;Petelenz, 1965;RYBACKand Mizeres. 1965;H udson, 1967;T ruex et a i, 1967;Verhaeghe and Van der Hauswaert, 1967;Merideth andTrrus, 1968: H romada andVoboril, 1970;Bojsf.n-M oller and T ranum-Jensen, 1972].…”