Reversal of the cardiac mechanism

The subject of investigation, H. M., came under observation at the Vanderbilt Clinic July 15, 1912. He has had a persistent diarrhea for a year with several watery stools a day. Otherwise he has been well until three months before admission to the clinic.

During these three months and subsequently, he has suffered from attacks of dizziness of increasing severity. In one of these attacks he fainted and fell in the street. Muscular effort increases the giddiness. He has had a good deal of headache. He is very drowsy and is annoyed by numbness and tingling of the hands and feet.

Until the onset of symptoms he had been a heavy drinker. He denies lues and gonnorrhea. The Wassermann test was negative. The blood and urine are normal. The heart is not enlarged. The sounds are faint but clear, and there are no murmurs. The third sound has been distinctly audible at most examinations and has been recorded graphically. The pulse is regular, 40 per minute. Systolic bloodpressure varies between 95 mm. and 110 mm. and diastolic pressure is usually about 65 mm. The electrocardiograms show that the heart beat is initiated by the ventricles, the auricular beat succeeding the ventricular after the usual conduction interval. This is evidenced by the presence of an inverted P between R and T in leads II and III. In lead I, P is of very small amplitude, but can be clearly distinguished on close inspection and stands in the same relation to R and T as in the other leads.

This interpretation of the electrocardiograms has been confirmed beyond reasonable doubt by examination with Roentgen rays and fluoroscope. The contractions of the auricle can be distinctly seen.