The Significance of the Diastolic Waves of T H E Venous Pulse In" Auricular Fibrillation. by Carl

In a previous study of the photographic venous tracings taken from clinical cases of fibrillation, 1 it was shown that the types of waves occurring during systole could be satisfactorily harmonized with and explained by photographic tracings previously obtained from animal experiments. The diastolic waves, however, could be given several different interpretations. This phase of the subject was, therefore, submitted to further experimental investigation. The plan of study resolved itself into several phases. In the first place, it was desirable to determine whether large diastolic waves in the jugular tracings and in the electrocardiograms of many cases are diagnostic of a state of coarse fibrillation or associated flutter, or whether they are also present during fine fibrillation. Anticipating somewhat the results presented later, it was found that although coarse fibrillation was accompanied by somewhat larger diastolic waves, vibrations of considerable amplitude could be present during a state of fine fibrillation. In the electrocardiograms the diastolic waves were sometimes larger during the state of fine fibrillation. The second phase of the experiments concerned itself with the cause of these diastolic variations. I t at once became important to establish whether they represented pressure variations from the right auricle. To determine this, the right intra-auricular pressure was