Heart Block with Aneurysm of the Aortic Sinus.

Disturbances of conduction in the heart may be purely functional, when for example demands are made on the conduction path very early in diastole as seen in blocked and aberrantly conducted auricular extrasystoles (Scherf and Boyd, 1940), or when too many stimuli are presented for conduction within a short time as with the incomplete A-V block that always exists in auricular fibrillation. Conduction disturbances may also be due to vagal inhibition. They may occur transiently after pneumonia and influenza, and are well known in diphtheria; recently Neubauer (1942) found many examples of partial and complete block in 100 cases of diphtheria. Over-digitalization may through poisoning of the A-V node lead to prolongation of conduction time, partial, or complete block. A permanent block can be established through coronary sclerosis, coronary thrombosis, rheumatic heart disease, syphilitic gumma, and more rarely through diphtheria, tuberculosis, and carcinoma affecting the A-V node or bundle directly. Congenital complete heart block is also known, and a few cases were found by Yater (1929), Aitken (1932), Campbell and Suzman (1934), and Currie (1940). The exceptional event of heart block as a result of direct trauma to the chest wall is described by Coffen (1930), Walker (1933), and White (1937). The following is the report of a case in which complete heart block was associated with an intracardiac aneurysm and aortic stenosis.