The most important observations in regard to the "P" wave of the human electrocardiogram have been those concerning its changes in mitral stenosis. Various workers, including Einthoven,1 Krauss and Nicolai,2 and Samjoloff,3 have called attention to an increase in height and often also a broadening of the P wave in this disease. To quote the last:
Wir fanden ebenfalls bei Mitralstenose Verstärkung und meist auch Verlängerung der P-Erhebung. (We found likewise in mitral stenosis an augmentation, and generally also a prolongation of the P wave.)
Since the increase in the height of the P wave has been thought due to the auricular hypertrophy resulting from the narrowing of the mitral ring, it would be reasonable to believe that auricular hypertrophy, the result of any other pathological change, would have the same effect. Hence it has been the custom at this station to consider high