PULSE-PRESSURE IN HEALTH, WITH SOME NOTES ON THE INFLUENCE OF CARDIO-VASCULAR DISEASE
(1) Most boys examined (9 - I4 years)
have a pulse-pressure of 40 - 45 m.m. of mercury.
(2) Pulse-pressure of youths from 15 - 20 years is 40 - 50 m.m.
(3) The age-group 21 - 30, shows pulse-pressure mostly between 46 m.m. and 50 m.m.
(4) The age -group 31 - 40 tends to be 40 - 50 m.m. and above.
(5) Men of 41 - 50 years have a pulse-pressure of 40 - 50 m.m. with a considerable
number giving readings of 51 - 60 m.m. These latter are nearer 50 than 40 years of age.
(6) In the age-group 51 - 60, pulse-pressure rises to 56 - 65 m.m.
(7) The age of the subject plus 100 represents the maximum systolic pressure.
(8) Pulse-pressure is increased by physical exercise; also by emotional states up to the age of 10 years. For the 10 years following, the diastolic pressure increases proportionally with the systolic under Emotion, and a pulse-pressure of about the normal results. After 50 years, the systolic pressure rises relatively higher than the diastolic, and the pulse-pressure once more increases.
(9) In a not inconsiderable number of
men, a full meal definitely increases pulse-pressure. The action of alcohol is uncertain in this respect.
(I0) Pulse-pressure is unaltered, or even tends to increase in healthy men who are confined to bed for two or three weeks.
ii. PULSE-PRESSURE IN CERTAIN CARDIO-VASCULAR DISEASE.
I. The pulse-pressure in health, determined in a considerable number of persons from 9 - 60 years, whose physical condition was good, and who were all free from ascertainable disease, is 40 - 65 m.m. Hg.
2. This pulse-pressure figure varies in health within somewhat wide limits, for reasons both trifling and transitory.
3. Pulse-pressure estimations must be made, in cardio -vascular disease, under the same conditions as those governing the observations made in Part I. of this Thesis.
4. The various disturbing factors in the circulatory equilibrium of a healthy person operate to vary the pulse-pressure estimation in sick persons, and must be obviated.
5. Nearly 100 patients suffering from common forms of cardio-vascular disease (with normal rhythm) have been examined, and the pulse-pressure findings discussed. High readings occur in Aortic reflux (with or without concomitant mitral disease);
in cardio -vascular hypertrophy, and in cases where this latter condition is associated with considerable myocardial degeneration. Although, strictly speaking, ttie cannot be regarded as suffering from cardiac disease, patients with
over-acting "nervous hearts" also have a high pulse-pressure.
In mitral stenosis, there is a marked tendency for the pulse-pressure to be low; normal or super-normal readings may however occur. In myocardial degeneration, non-specific or otherwise, with no complicating valve lesion and no marked vascular degeneration, exhibit a pulse-pressure little removed from normal.
6. The pulse-pressure figure is of definite value in those cases of heart disease which exhibit, on auscultation, an
anomalous diastolic bruit towards the left lower border or the sternum; or where exocardial sounds are heard. A high reading suggests Aortic reflux; a low reading is against this diagnosis.
7. Pulse-pressure estimation is of less value in the diagnosis of mitral stenosis. Although the reading is commonly low in these cases, it is also frequently found to be within normal limits of the age -group concerned; these latter are often
the "early cases ". When the valve lesion has definitely declared itself, the pulse-pressure certainly becomes abnormally small, its diagnostic worth, however, in these later cases is, obviously, less.
8. The high pulse -pressure in Iyperpiesis, and in those patients with a combination of myocardial degeneration and supernormal blood-pressure, may wrongly suggest the diagnosis of Aortic reflux. Similarly, the "normal" reading obtained in many cases of myocardial degeneration, and in mitral stenosis, ma suggest a healthy heart where physical signs are few, and clinical examination is hurried.
9. Pulse-pressure estimation cannot displace any accepted method or clinical examination in cardio-vascular disease, but may prove an extremely helpful adjunct to it.