THE USE OF INDIRECT ARTERIAL PULSE TRACINGS IN THE DIAGNOSIS OF CONGENITAL HEART DISEASE

Abstract

The femoral, radial and carotid pulse curves of 22 normal patients and 33 patients with coarctation of the aorta were studied by indirect means using a crystal microphone and a standard electrocardiograph machine for recording purposes. In general, certain definite abnormalities can be noted in the pulse tracings of patients with coarctation when compared with the normal group. In the normal patients, the femoral and radial pulsations began, on the average, simultaneously, whereas in the patients with coarctation of the aorta, there was an average delay of 0.01 second in the onset of the femoral pulsation as compared to the radial. There was considerable variation in both normal patients and those with coarctation, however, in the relative time of onset of the two pulses. This variation renders the use of the time of onset of the two pulses a poor diagnostic criterion for coarctation of the aorta, unless the femoral delay exceeds 0.02 second. It was also demonstrated that the relative priority of onset of the femoral or radial pulsation had little relationship to the age of the patient or the relative proximity to the heart of the two pulses, but more probably was dependent upon the speed of propagation of the pulse wave to the two extremities. More valuable information, from a diagnostic standpoint, can be derived from analysis of the contour of the femoral pulse curve and its relationship to the carotid pulse curve. The patients with coarctation of the aorta showed a definitely prolonged ascent of the femoral pulse, regardless of the time of onset in relation to the radial. The time interval between the peak of the femoral pulse wave and dicrotic notch of the carotid pulse was constantly considerably less in the patients with coarctation than in the normals. It is felt that pulse wave recording by indirect means reflects the pulse curve relationships derived by direct arterial puncture with satisfactory accuracy and gives the same useful information in the diagnosis and postoperative follow-up of cases of coarctation of the aorta. In addition, it is simpler and quicker than direct arterial puncture and is associated with no discomfort for the patient.