The paradox of pressure: When the heart's saving process becomes a fatal disease

“ All the conflict during the past few years over the subject of blood pressure has revolved around this much overworked word. Hypertension means high pressure, and yet it carries with it a suggestion of high pressure which is harmful to the individual. As a matter of fact hypertension is a compensatory process, it is often a saving process in spite of the fact that it carries possibilities of harm in its possessor. ”

“ Hence the clinical measuring of the pressure in the brachial artery alone is not sufficient for a diagnosis of arteriosclerosis. A persistent high blood pressure even with normal urinary findings is not a sign of arteriosclerosis. The high tension later may lead to the production of sclerosis of the arteries, but in these cases the kidney may be primarily at fault.
The impression must not be gained that hypertension in [186] itself always constitutes a disease or even a symptom of disease. Hypertension itself is practically always a compensatory process. ”

“ That is to say, it is the attempt on the part of the body to equalize the distribution of blood in the body when there is some poison causing constriction of the small arteries. In this sense hypertension is not only essential, but actually life-saving. A heart which is so diseased that it can not respond to the call for increased action by hypertrophy of its fibers, would shortly wear out. The very fact that the heart becomes enlarged and the tension in the arteries becomes high, indicates that in such a heart there was great reserve power. ”

“ The blood pressure may be sufficient, or even increased if arteriosclerosis is present, although the rise of the sphygmograph tracing is not so high as normal. If the pressure in the aorta is sufficient from the amount of blood forced into it, the coronary arteries receive enough blood to keep up the nutrition of the heart muscle. Sooner or later, however, the left ventricle will become weakened, especially when there is arteriosclerosis or other hypertension, and chronic endocarditis and fatty degeneration result. ”

“ Hypertension is generally a prelude to arteriosclerosis, and everything which tends to increase tension promotes the disease; everything which tends to diminish tension more or less inhibits the disease. Therefore a subsecretion of the thyroid predisposes to arteriosclerosis, and increased secretion of the suprarenals predisposes to arteriosclerosis, the thyroid furnishing vasodilator substance and the suprarenals vasopressor substance to the blood. ”

“ There is usually the enlarged heart and pulse of high tension with or without the trace of albumin in the urine. The lurking danger of this group of manifestations has so impressed the medical directors of several of the large insurance companies that a blood pressure reading must be made on all applicants over forty years of age. Should high blood pressure be found, the premium is increased, as the expectation of life is proportionately shorter in such men than in normal persons. ”

“ But when we come to consider cardiac strain a little more closely, it may be just as easily maintained that every dilated heart, every dilated cardiac chamber, every dilated blood-vessel has been strained. Whether, on the one hand, valvular disease, Bright's disease or emphysema, or, on the other hand, myocardial degeneration, has disturbed that cardinal condition of a normal circulation that the driving power must always exceed the resistance ahead, over-distension and dilatation of the cavities, with excessive stretching of their walls, constitute or consist in mechanical strain. ”

“ At 65, other changes which occur in the heart and arteries are not less striking than those which I have just described. The decline of circulatory energy, and the effects of time itself on the protoplasm of the cells of the body, have so lowered the metabolic and functional energy of the tissues and organs and the activity of the blood-supply, that a considerable proportion of the capillary network becomes obsolete. The peripheral resistance is thus increased, and the blood-pressure rises ”

“ A force which is sufficient to send blood through elastic normal distributing tubes becomes totally insufficient to send the same amount of blood through tortuous and more or less inelastic tubes. As a compensatory process the pulse pressure increases. For this to increase, the left ventricular cavity dilates, the arch dilates, and as a greater force must be exerted to keep the increased mass in motion, the heart responds by hypertrophy of its left ventricle and becomes itself the subject of fibrous changes in the myocardium. ”

“ The skin and abdomen together make up so large a part of the whole body that marked constriction of the blood vessels in these two regions is bound to cause a considerable increase in blood pressure.
A fairly high blood pressure is necessary for bodily well-being, because only thereby is the brain assured of sufficient nourishment. To see why this is so, we have only to remember that the brain is unfavorably situated for receiving ample supplies of blood. It is at the top of the body, so that the influence of gravity has to be overcome in forcing blood up to it. ”

“ The residual air in a lung is the basis of the respiratory process; the sustained tension of the smaller arteries transforms the pulsating current of blood thrown into the system by the heart to a continuous circulation; the equilibriated tonicity of opposing muscles gives stability to the apparatus of motion, and renders specific combinations of movement possible. ”

“ The economy is witnessed here in the easy means adapted for converting without complications a spasmodic flow of blood into a continuous stream; insuring also that the amount of of blood which flows from the arteries to the veins during the heart's stroke and pause exactly equals that which enters the circulation at each contraction of the ventricle. In other words, the tremendously high pressure of the arteries of our bodies saves at once the multiplication of bodily pumping-engines and conserves the force of the heart itself. ”

“ But if stimulation of the brain does not paralyze, it must increase the tonicity of the vaso-motor centre, and hence the force and regularity of the circulation. Up to a certain point, these characters do indeed increase, with increase of pressure in the cerebral blood-vessels. They increase also during intellectual operations, unattended by emotion, in which a similar increase of pressure must take place, on account of the afflux of blood to the cerebral hemispheres, when these are aroused to activity. ”

“ An effort of the will may and does dilate the blood-vessels of the brain, and permits larger circulation through it; but the general blood-pressure in the systematic vessels is an important matter in sustaining the intercranial flow. If the general blood-pressure in the vessels of the head and neck is high and well maintained, then a brain can work up to a much higher power, just as a steam-engine may be worked up to a higher pressure, and so become actually more powerful. ”

“ Increased muscular activity is developed in accurate proportion to the rise of internal pressure and secures sufficient output from the heart. This, I repeat, is what occurs in the sound heart. Now, in old parietal strain extensibility and the reserve of capacity of the chambers which it insures are seriously exhausted; whilst the muscular function is only maintained by means of hypertrophy, to which there is necessarily a limit. In these cases of strain it is impossible to reduce the original dilatation—that is permanent. ”

“ We know that organs exposed constantly to hard work undergo hypertrophy, and that the blood tension in those organs is high. Blood tension is, after all, dependent on capillary resistance, and if the capillaries are distended with blood, the resistance is great. The digestive organs can be no exception to this rule. Increased work means an increase of blood. This inevitably causes distension of the capillaries with stretching of the arteries and consequent damage to the walls. Once arteriosclerosis is present a vicious circle is established. ”

“ With high blood pressure to the point of beginning endarteritis, a gradually increasing force of the apex beat occurs, the aortic closure is accentuated as just described, the pulse is slow, the tensity of the arteries depends on the stage of the disease, and when the disease is actually present, the palpable arteries do not collapse on pressure. They soon lose their elasticity, and if this occurs in parts which are soft and flexible, the arteries become more or less tortuous by the force of the blood current twisting and bending them, owing to the irregularity of their hardening. ”

“ Where the disease is met with in middle life, in those who daily undergo severe mental or bodily strain, the prognosis is unfavorable. And when in such patients there are the evidences of arterial degeneration or a tendency to it, the dangers are greatly increased, for the hypertrophied ventricle drives out the blood from its dilated cavity with greater than the normal force, and the vessels being weakened there is great danger of their rupture ”

“ We can not ignore the part which heredity plays. The various factors to be considered in the production of the acquired form of arteriosclerosis appear to me to be but contributory factors to a very great extent, the essential and fundamental factor being the quality of arterial tissue with which the individual is endowed.
Arteriosclerosis may occur in infants. Cases have been reported of calcification of the arteries in infants and children. The arteriosclerosis may occur without nephritis or rise of blood pressure. ”

“ As a matter of fact in the severest grades of senile arteriosclerosis the blood pressure is usually below the normal for the individual's years. However, as high tension is a frequent factor in the production of arterial thickening, blood pressure readings are of importance.
The instrument which one uses is of minor importance provided it is properly standardized. The most important feature of the instrument is the cuff. This must be 12 cm. wide and be long enough to wrap around the arm several times so that the pressure is evenly distributed over the whole arm and not over a small portion. ”

“ While the systolic range from youth to over 60 years of age gradually increases, at the younger age anything below 105 mm. of mercury should be considered abnormally low, and although 150 mm. at anything over 40 has been considered a safe blood pressure as long as the diastolic was below 105, such pressures are certainly a subject for investigation, and if the systolic pressure is persistently above 150, insurance companies dislike to take the risk. ”

“ High blood pressure just by itself might not mean much more than that the heart was beating more rapidly than it should, but a high maximum pressure and a low minimum pressure means nonelastic arteries. This in turn means that the blood is forced through the capillaries in jets rather than in a steady stream, and we may judge of the importance of having a steady flow through the capillaries when we recall the well-known medical proverb that “a man is as old as his arteries.” It is an actual fact that the chronological age of an individual need not have much to do with his physical age. ”

“ Louis M. Warfield, in his work on Arterio-Sclerosis, says: “It is most important to estimate accurately the diastolic pressure as well as the systolic, for only in this way can we obtain any data of value regarding the driving power of the heart and the condition of the vaso-motor. A high systolic pressure does not necessarily mean that a great deal of blood is forced into the capillaries. Actually it may mean that very little blood enters the periphery. The heart wastes its strength in dilating constricted vessels without carrying on the circulation43 adequately. ”

“ Lead may be a cause of increased blood pressure, and diabetics occasionally have a high pressure, although more frequently there is a lowering of blood pressure in diabetes.
Richman believes that syphilis is the most common cause of hypertension and arteriosclerosis without renal disease. When arteriosclerosis and renal disease are combined, of course the highest systolic readings occur. He thinks that when high tension occurs under 40 years of age, kidney disease is generally the cause. ”

“ If the heart shows signs of loss of power, minor operations to cut off the blood supply of the thyroid should first be done, and the patient's heart allowed to improve before a thyroidectomy is performed.
Men with hypertension without kidney or arterial excuse are likely to have been athletes, or to have done some severe competitive work, or, as above stated, to have labored hard, or to have worked at high tension, or in great excitement, or with mental worry, all of which tend, as long as there is health, to increase the blood pressure. ”

“ Moderation and due respect for age are the true guides to the useful enjoyment of exercise after 40. As for the evil effects of nervous influences on the circulation, in addition to anxiety, care, misfortune and grief, which are usually beyond our control, nervous strain, as distinguished from simple hard intellectual work, often must be relaxed if cardio-vascular damage is to be prevented. I refer to the cases of persons in positions of great responsibility with heavy complex prolonged duties, which they fail to overtake without exhaustion consequent on high pressure and excitement. ”

“ Hurry and "High Pressure." — It is the pace that kills; and of all forms of "overwork," that which consists in an excessive burst of effort, straining to the strength, and worrying to the will, hurry of all kinds — for example, that so often needed to catch a train, the effort required to complete a task of head-work within a period of time too short for its accomplishment by moderate energy — is injurious. ”

“ There exist two chief agencies for the production of arteriosclerosis: 1. A hyperactivity of the adrenals, causing a rise in blood-pressure. 2. A degeneration of the thyroid gland, which, when normal, antagonizes the first by lowering the blood-pressure. Although from the above-mentioned facts high blood-pressure cannot be considered as the chief cause of arteriosclerosis, still no doubt it certainly contributes to it; for each time that there is a rise in the blood-pressure more blood is forced through the arteries, thereby causing them to dilate ”

“ Sometimes when the blood pressure is not lowered, there is relief of tension in the head from high pressure, and the patient feels better. There is also relief of the heart when it is laboring to overcome a high resistance. One drop of the official spirit of nitroglycerin on the tongue will cause a lowering in the peripheral pressure pulse, the radial pulse becoming larger and fuller. ”

“ In obese patients with hypertension, in the hypertension of women at the menopause, and in hypertension with insufficient kidneys, thyroid medication is often of great value. Sometimes a small dose of from 0.1 to 0.2 gm. (1 1/12 to 3 grains) once a day is all that is needed. At other times, especially when there is no marked arteriosclerosis and no marked kidney or liver lesion, very high blood pressures are reduced only by very large doses, even as much as 10 grains a day. Such treatment is often of very great benefit. ”

“ Some very high tension cases, especially in women at the menopause, and where there is no kidney involvement, have the blood pressure reduced successfully only by large doses of thyroid, sometimes well combined with bromids, especially if the thyroid causes excitation. ”

“ It may save a heart that is in agony from tension, and may prevent an apoplexy. It is of little value except temporarily in uremic conditions, but at other times it may, at the time, save life and allow other methods of reducing the dangerous tension to become effective. A chronic high tension patient may be repeatedly bled, although such treatment will not long save life, as the blood pressure in many such cases soon returns to its previous height. ”

“ When more or less active treatment does not soon lower the hypertension, and especially a high diastolic pressure, the prognosis is bad. In a patient who is in more or less immediate danger from his hypertension, the food and liquid taken, the care of the bowels, and the measures used to cause secretions from the skin must all be governed by the condition of his other organs. There is no excuse for excessive, strenuous measures when the heart is failing or when the kidneys are becoming progressively insufficient. ”

“ However, if there is a high systolic and a low diastolic pressure, vasodilators are often contraindicated.
TREATMENT In this rapid high tension age the physician should be as energetic in teaching prevention of arterial hypertension as he is in preventing contagion. As infectious diseases are reduced in frequency, more patients live to die of diseases later in life, and (as previously stated) diseases with hypertension are on the increase. It is therefore the duty of the physician to urge youths and adults to abstain from all kinds of excesses so common in this age. ”

“ It has been shown how poisonous substances absorbed from the intestines have some influence on the blood pressure. Anything that causes constant increase of pressure should be studiously avoided.
Mild exercise is an essential feature of prophylaxis. One may, by judicious exercise and diet, make of himself a powerful muscular man without, at the same time, raising his average blood pressure. The man who goes to excess and continually overburdens his heart, will suffer the consequences, [226] for the bill with compound interest will be charged against him. ”

“ Lead, tobacco, and according to some, tea and coffee, are to be classed as causal factors in the production of arteriosclerosis. Certain it is that all these substances have a tendency to raise the arterial pressure, but whether the drug itself causes first a degeneration, and later a hypertension results, or vice versa, is not yet positively known. We have just mentioned that lead particularly has a marked effect in producing arterial lesions. Other drugs as adrenalin, barium chloride, physostigmin, etc., while producing experimental arteriosclerosis, hardly could produce the disease in man. ”