TREATMENT It is not possible to remove the organic changes associated with pericardial adhesion, hence the object of treatment is to minimize and delay, so far as possible, their injurious effect on the heart. The nutrition of the myocardium must be promoted and maintained by suitable hygienic, dietetic, and medicinal means, and all sources of cardiac strain should be carefully avoided. A more detailed description of the measures by which these indications are carried out will be given under the account of the treatment of affections of the myocardium. The treatment of cardiac failure should be conducted on general principles, but care must be observed in the use of cardiac tonics. SECTION III HYDROPERICARDIUM Dropsy of the pericardium is due either to (a) general or (¿) local causes. Under the first head the hydropericardium is usually one of the phenomena of general dropsy consequent on disease of the heart, kidneys, or lungs, but it may appear, in common with effusion into the other large serous sacs, during the early stages of acute Bright's disease, or in the course of the cachexia associated with tuberculosis, cancer, and the graver forms of anæmia, etc. In rare instances hydropericardium depends on a local obstruction to the circulation through the pericardial and cardiac veins caused by thrombosis of these vessels, or by pressure upon them from without, etc. Dropsy of the pericardium is rarely large in amount. It gives rise to the signs which have already been considered in connection with pericarditis with effusion. Hydropericardium may, however, be distinguished from pericarditis with effusion by (1) the history of one or other of the conditions mentioned above, (2) the absence of fever, (3) the absence of friction signs, and (4) the presence of general œdema and of effusion into the other large serous cavities. The treatment of hydropericardium is that of the primary disease. A large effusion may necessitate paracentesis of the pericardium. SECTION IV HÆMOPERICARDIUM Hæmorrhage into the pericardial cavity is usually due to the bursting of an aneurism of the first part of the aorta, or of one of the coronary arteries, or to rupture of the wall of the heart, the result of traumatism, or disease of the myocardium. It may also occur, to a much slighter extent, in pericarditis due to tubercle, cancer, or scurvy, and it occasionally depends on the rupture of recent pericardial adhesions. The clinical phenomena associated with this condition depend, to some extent, on the rapidity of the bleeding into the pericardial sac. If the hæmorrhage takes place gradually, præcordial pain, urgent dyspnoea, syncopal attacks, collapse, and evidence of loss of blood may usher in the fatal termination. A physical examination of the chest, when it can be made, discovers the signs of fluid in the pericardial cavity. The sudden discharge of a large quantity of blood into the pericardial sac usually leads to sudden death. Treatment can be palliative only. SECTION V PNEUMOPERICARDIUM Pneumopericardium, as a clinical phenomenon, is an exceedingly rare condition. The means by which air or gas gains access to the pericardial sac is either a wound of the thorax involving the parietal layer of the pericardium, or the establishment of a communication between the pericardium and an air or gas-containing organ, such as the œsophagus, lungs, or pleuræ, stomach or intestines. In the second and more common event the extension to the pericardium of suppurative or ulcerative processes affecting one or other of these viscera is the determining cause of the perforation of the membrane. Pericarditis quickly follows the entrance of air or gas into the pericardial cavity, and since the effusion which accompanies the inflammatory process is almost invariably purulent, a condition of pyopneumopericardium, rarely of hydropneumopericardium is produced. The spontaneous development of gas in the pericardial cavity, consequent on the presence of gas forming bacilli, is postulated by some observers. The symptoms associated with pneumopericardium are practically those of purulent pericarditis. The physical signs are often very remarkable and are characteristic of the presence of gas and fluid together in the pericardial sac. Bulging of the præcordial area is sometimes very pronounced. The hand placed over the heart occasionally experiences a succession of small shocks or vibrations due to the bursting of air bubbles at the surface of the fluid. In the recumbent posture a clear tympanitic percussion note is obtained over the cardiac area, and when the opening into the pericardial sac is patent, a cracked pot sound may be elicited. If the patient is made to sit up and lean forwards, the tympanitic note is replaced over the lower portion of the præcordial area by a dull sound, in consequence of the displacement of the gas by fluid, under the influence of gravity. For a similar reason a partial replacement of the lateral extent of the area of resonance by dulness can be effected by turning the patient to one side or the other. The sounds of the heart have a characteristic metallic quality, and are described as splashing, gurgling, churning, etc. They have also been compared to the sound produced by a water-wheel in motion. An amphoric echo of the heart sounds, and of pericardial friction sound, etc., has been observed in some instances. In the presence of the physical signs just mentioned the diagnosis of pneumopericardium presents no difficulty. The prognosis is very unfavourable, but recovery has been recorded in cases due to injury. There is little scope for treatment, which should be conducted on the lines indicated under the head of " Acute Pericarditis." The question of operative procedure, in the shape of paracentesis pericardii, or of free drainage of the pericardial sac, has to be taken into consideration in every case. SECTION VI NEW GROWTHS The more important new growths which may affect the pericardium are tubercle, carcinoma, and sarcoma. Tubercular disease of the pericardium is uncommon, and its occurrence is usually secondary to tubercular disease elsewhere. A primary form of pericardial tuberculosis associated only with caseation of the bronchial or anterior mediastinal glands is described by_Osler. In a large number of instances the implication of the pericardium is due to the direct extension of tubercular disease from the lungs. The pericardium is very rarely affected in cases of general acute miliary tuberculosis. Carcinoma of the pericardium is very rare and always secondary. The pericardium usually becomes involved by the direct extension of the growth from neighbouring structures. The sarcomata are nearly always secondary, and are of the spindle or round cell variety. Lymphosarcomata commonly originate in the mediastinal tissue and attack the parietal layer of the pericardium almost exclusively. Syphilitic affections of the pericardium are almost invariably secondary to lesions of the myocardium. New growths of the pericardium usually give rise to chronic inflammation of the membrane, attended, in many instances, by effusion of blood or pus. Clinically, the implication of the pericardium in a new growth may be suspected when the symptoms and signs of pericarditis are observed in conjunction with tubercular disease of the lungs or other organs, or with an intra-thoracic tumour. The prognosis is, of course, hopeless, and treatment can be palliative only. CHAPTER VIII ACUTE ENDOCARDITIS Classification-Section I. Acute Simple Endocarditis-Section II. Malignant or Infective Endocarditis. INFLAMMATION of the endocardium may be either acute or chronic, and in the large majority of cases the morbid process is limited to the valves of the heart and their tendinous attachments. It is customary to distinguish two kinds of acute endocarditis, viz. :— 1. Acute simple endocarditis 2. Acute malignant or infective endocarditis This division of the subject is not altogether satisfactory, either from a clinical or pathological point of view, but it is the most suitable for descriptive purposes, and will therefore be adopted. SECTION I ACUTE SIMPLE ENDOCARDITIS ÆTIOLOGY Acute simple endocarditis arises most commonly in the course of an attack of acute or sub-acute rheumatism, and may precede, accompany, or follow the affection of the joints. It occurs in about 50 per cent. of the cases of acute rheumatism, and the liability of the endocardium to be affected increases with repeated attacks of rheumatic fever. Endocarditis of rheumatic origin occurs more frequently in children than in adults, and the vulnerability of the endocardium appears to be most marked between the ages of four and twelve. The large majority of the cases of rheumatic endocarditis occur in persons under thirty years of age, and women suffer rather more frequently than men. There is no relation between the occurrence of endocardial inflammation in acute rheumatism and the amount of pyrexia, or the severity of the joint implication. The endocarditis which arises in the course of a considerable number of cases of chorea is, probably, of rheumatic origin. Acute endocarditis is also observed in connection with the acute zymotic fevers, more especially with scarlet fever and measles. It occasionally arises in association with enteric fever, variola, diphtheria, and with other septic conditions, such as erysipelas, puerperal fever, septicemia, and pyæmia. In some instances it has occurred as a complication of pneumonia, syphilis, and gonorrhoea. Among other occasional causes of endocarditis may be mentioned such disorders as gout, acute nephritis, and diabetes. Acute and chronic tuberculosis are sometimes accompanied by endocardial inflammation, and in a few instances the tubercle bacillus has been demonstrated in the affected parts. Several cases have been recorded in which endocarditis has followed a blow on the chest. Here the endocardial inflammation depends in all probability on the rupture or tearing of a valve. The occurrence of acute simple endocarditis as a primary or idiopathic affection is mentioned by some observers, but it must be an exceedingly rare event. The exclusion of a rheumatic origin must be very difficult in cases of this kind, since it is probable that endocarditis is, in some instances, the sole expression of the rheumatic state. The presence of old-standing valvular disease, the result of acute or chronic inflammation, or of degenerative changes, is a powerful predisposing cause of acute endocarditis. Endocarditis may be hereditary in so far as the diseases with which it is associated are hereditary. Unhealthy hygienic surroundings, poverty, and exposure are of influence in the causation of endocardial disease, by reason of the fact that such conditions predispose to rheumatism and other disorders which may give rise to endocarditis. PATHOLOGY AND MORBID ANATOMY The inflammatory changes in acute endocarditis are usually limited to the valves of the heart and their tendinous attachments, by reason of the greater strain to which these structures are subjected as compared with the rest of the endocardium. Furthermore, the morbid process in adults is almost invariably confined to the valvular apparatus of the left heart. This is accounted for on the grounds that the endocardium is rendered more vulnerable by the higher blood pressure and greater variation of intra-cardic tension which obtain on this side of the organ. For a similar reason foetal endocarditis most commonly |