Any of these disturbances of the circulation through the heart cannot exist without changes being produced in the heart itself. Whether it be that there is an obstacle to the flow of blood through the heart, or that part of the blood that should pass onwards returns, the first effectors the heart, and specially the chamber first affected, is that it begins to enlarge. This is partly because it works harder to perform its task, which has become more difficult, increase of growth occurring to meet the increased de mand for energy, and partly because the in creased quantity of blood, always in it, produces a distension of the walls to afford increased accommodation. The heart enlarges in its sub stance, that is, it suffers hypertrophy (over growth), and it also suffers dilatation (over distension). But the changes are not limited to the heart ; they in time affect the whole body. If the ventricle becomes overfull, because of disease of the valves 'of the aorta, that will speedily produce a similar condition of the upper chamber, the pressure passing backwards. Since the auricle receives its blood from the lungs (p. 309), and since the blood does not get passing onwards quickly enough, the lungs will, by and by, begin to feel the backward pressure, and become more or less blocked with blood also. Since the lungs receive the blood from the right side of the heart, the pressure will travel back wards to the chambers on that side, and they in turn will become overfull. Moreover, the blood arriving in the right side of the heart comes from the head and neck, some of it directly from the liver and also from the trunk and lower part of the body, and that coming from the liver is the blood from the stomach and bowels, &c. The blocking will, therefore, travel ever backwards and backwards to these organs, so that the veins of head and neck, liver, sto mach, &c., will become congested. Just as, if you have a large number of streets and lanes opening into a main thoroughfare, along which crowds of people are streaming, if one end of the main thoroughfare becomes partly blocked and the crowds still stream on, that thorough fare will speedily become blocked from one end to the other, and then the lanes and adjoining streets will in turn become crowded with the people who cannot get on. Of course if the people could be made to pass off some other way the blocking would soon be got rid of ; but the blood must all go on in the destined course, there is no side way by which it can escape, and as time goes on the congestion becomes worse and worse. Another thing to note is that while the veins bringing the blood to the heart all become unduly full, the arteries do not contain sufficient blood, because the blood is not escaping in a full enough stream from the left side of the heart, and thus the various organs cease to be duly nourished, while at the same time they are congested with blood. Thus it becomes clear how, from valvular disease of the heart, congestion of the lungs, liver, kidneys, stomach and bowels, brain, &c., arises, and how consequently shortness and difficulty of breath ing, with an attendant livid hue of the skin, jaundice, indigestion, kidney disease, headache, giddiness, convulsions, &c., may be occasioned. Moreover, fluid oozes out of the overcharged veins and dropsies arise. Meanwhile the heart itself suffers from defective nourishment, and its labour becomes too great for its strength. It becomes weakened, and with its commencing failure the consequences of its disease are at once aggravated.
Now, while such is a sketch of the conse quences of an aggravated case of valvular dis ease, it is not to be supposed that all cases of valve disease run a similar course. Such is very far from the truth. There is no manner of doubt that many people have some imper fection of the valves of the heart and never become aware of it, but are able to lead active lives without being aware of any symptom that leads them or others to suspect any unusual condition of the heart. An average length and an ordinary vigour of life are not inconsistent with some forms of valvular disease. That is why doctors frequently refrain from informing patients of such a condition they may know to exist there. For heart disease is a phrase of terror to many, and the knowledge that they were, in even the smallest sense, subjects of it would seriously affect their lives, while they might live long and useful lives in blissful ignorance, and die, perhaps, of some disease entirely unconnected with disorder of the heart.
Further, though sudden death is a result of some forms of disease of the valves, it is not so common as was at one time supposed.
Another result of affection of the valves re mains to be mentioned. The roughened condi
tion of the valves sometimes causes fibrin to be separated from the blood, and to be deposited in little clots on their edges. The clots may become detached and swept away in the current of blood. They pass easily through the larger vessels, but at last reach vessels too small to permit their passage, which they block up. This blocking of small vessels by detached clots is called embolism, and is referred to on p. 326. Sudden death is a common result of this, a clot finding its way to the brain, and blocking a vessel, cuts off the blood supply to a part of the brain, and sudden paralysis or unconsciousness is the result.
The causes of the disease are acute rheu matic fever in particular, St. Vitus' dance, scarlet fever, Bright's disease of the kidneys, syphilis, &c.
Symptoms.--General symptoms have already been indicated in the sketch given of the results, affections of the lungs, congestion, bronchitis, &c., with attendant lividness of the skin, diffi culty of breathing, jaundice, indigestion, disease of the kidneys, with scanty, high-coloured urine, and nervous symptoms, headache, giddiness, &c. Connected with the heart itself there are things to be noted. The beat may be feeble or exces sive, and it may be irregular. Palpitation- frequent, sudden, and violent beating of the heart is common. But it must not be forgotten that palpitation, irregularity of the heart's beat, and a form of irregularity, called intermission, in which a beat is missed and the person feels a throb or tremble or fluttering sensation, perhaps with a feeling of choking, are far more com monly due to indigestion, specially indigestion with flatulence, than to heart disease. Many people, particularly women, are convinced they suffer from heart disease because of palpitation and the very uncomfortable sensations it pro duces, when all the time there is nothing but a stomach derangement to blame.
The special signs of disease of the valves of the heart, whose discovery alone justifies one in declaring the disease to exist, are such as a per son cannot easily detect in himself. They are found by an examination of the chest, and by listening to the sounds produced by the con tracting heart. A physician will find at what part of the wall of the chest the heart beat is felt most distinctly, and will see whether it is in the right position; he will examine by per cussion—by tapping the cheat as indicated on p. 319 —to determine whether the heart is the usual size or is enlarged ; and he will employ auscultation — that is, he will listen with his ear to the chest wall or by means of the stetho scope—to hear the sounds of the heart, in order to learn if they are of the usual character. For the sounds noted on p. 303 will be altered if disease of the valves be present. If a valve be diseased, one of the sounds will be replaced or attended by a blowing murmur, and the relation in point of time which the murmur bears to the heart sounds will indicate which valve is affected. A skilful man will exercise caution, because a temporary murmur may be produced by pressure or other circumstances, bloodlessness of the patient, for example, which might without care be mistaken for the sound of a diseased valve. In rare cases the peculiar sound has been loud enough to be heard by the patient himself and those standing near him; commonly it requires to be examined for.
The treatment of valve disease depends on various circumstances. If it is a complication of some other disease, rheumatism, &c., clearly that other disease requires attention. A person who has had rheumatism should exercise great care to avoid cold, draughts, wettings, &c., that would readily excite a second attack. General treatment of the disease consists in avoidance of all excitement--running, hurrying for trains, jumping, mounting long stairs, in fact every thing involving exertion. Fits of anger, out bursts of emotion, &c.,shonld equally beavoided. The bodily health should be carefully main tained by judicious eating and drinking, and over-eating, the excessive use of tea, tobacco, and stimulants, &c., should be rigorously guarded against. The health may be benefited by change of air, iron tonics, &c. If distressing symptoms, such as palpitation, difficulty of breathing, &c., arise, they will be much relieved by complete rest. Drugs, and in particular digitalis, are used to strengthen and calm the heart, but how and when they should be used ought to be deter mined by a medical attendant.
A most successful method of treating some heart affections, including recent valve disease in the young, is by Nauheim baths (see p. 487, Vol. II.).