Studies in Intracardiac Electrography in Man

Abstract
Two parallel researches in progress at the Brigham Hospital, one an investigation of intracardiac electrography in general, the other a long-term study of heart muscle metabolism with the aid of the venous catheter, converge, resulting in the interesting practical and theoretical findings reported here. The authors show how the electrogram may help establish the position of the catheter in the coronary venous system and indicate the type of potential variations recorded in the coronary sinus, in its continuation, the great cardiac vein, and in its tributary, the middle cardiac vein.