SINO-AURICULAR HEART BLOCK

Abstract

While abnormalities in conduction and partial or complete blocking of the cardiac impulse at the auriculoventricular junction is a fairly frequent clinical condition, similar disturbances at the sino-auricular junction are apparently exceedingly infrequent in the higher animals and in man. So far as we have been able to find, only four clinical cases in which the diagnosis was satisfactory have been reported. The first case was reported by Mackenzie¹in 1902, in a patient during an attack of influenza. The second case was reported by Wenckebach²in 1906, in a man, aged 30, who was apparently normal aside from the disturbance in the heart rhythm. The third case, described by Hewlett³in 1907 and the fourth by Rihl⁴in 1908 were in cases of advanced cardiac and arterial disease. In all of these the diagnosis was made by the aid of the venous pulse and rests