Symptoms.—The horse stands quiet, showing signs of pain and anguish, with sunken head, anxious expression in the face, dilated nostrils, frequent (100 to 120), wiry, and sometimes IRREGULAR or intermittent PULSE, and general intense fever.
The breathing is also accelerated (36) and difficult, and is accompanied by a movement of the flank similar to that seen in broken wind, and by a deep depression along the margin of the costal cartilages. In the early stages, pressure on the left side, and smart percussion in the region of the heart, cause flinching and expression of pain; and auscultation, before exudation has taken place, reveals friction—to and fro—sounds. These sounds are, however, not uniformly present in this disorder, nor is their presence an unquestionable proof of its existence, for similar sounds may be do to pleural disease, the latter being characterized by synchronism with the respiratory movements. The friction sounds are therefore of little value, except as concurrent with other symptoms. They also cease when exudation or adhesion has taken place; then the heart’s beats are muffled. In the later stages, the heart, which at first palpitates, soon becomes fluttering and uncertain in its beat, conveying a peculiar pulsation to the hand, not easily to be described. No impulse can be felt when the effusion is considerable. Percussion gives a dull sound over the region of the heart, but not so in other parts of the chest, where the respiratory and bronchial sounds may be heard, thus distinguishing Hydrops Percardii from Hydrothorax. The breathing gradually becomes more distressing, and movement aggravates the distress; the pulse more feeble and even imperceptible at the jaw; the ears and legs cold; the legs, sheath, chest, abdomen, etc., œdematous; and the general wasting rapid till death ensues.
Diagnosis.—The friction sounds, and pain on percussion in the region of the heart, with irregularity in its beats, and a peculiarly anxious expression of countenance, are the principal pathognomic symptoms—to which Delafond adds dyspnœa, attended by an action of the flank like that of a broken winded horse. The great difficulty is to distinguish this disease from Pleurisy, which may be done by accurately marking the period at which the frictional sounds occur, viz.: during the systole or beat of the heart, whereas for Pleuritis we hear it during the respiratory movements of the lungs. When the pericardial fluid becomes much increased, the friction sound ceases, as does also the impulse of the heart, which at first usually palpitates, then becomes fluttering, feeble, and intermittent, and at last can with difficulty be heard. Percussion gives a dull sound in the region of the heart, but just behind it, as well as in other parts of the lungs; if there is no disease in them, or Hydrothorax, the resonance in those parts will serve to distinguish Hydrops Pericardii from Hydrothorax.
Prognosis.—In the strong, and in the majority of cases, favorable.
Treatment.—A.A., given every three hours, and later, four times per day, will be proper.
Endocarditis
Definition.—Inflammation of the fibro-serous membrane which lines the heart.
This is a very common complication in Rheumatism, and is very acute and dangerous; the danger arising less from the fatality of the acute stage, than from the lesions which are consequent upon it.
Symptoms.—In Endocarditis the contractions of the heart are energetic, vibratory, and often irregular; the pulse is also irregular, and frequently intermittent, and there is a contrast between the feebleness of the pulse and the violence of the heart beats. Leblanc states that this last symptom is characteristic of Endocarditis. He has also observed a loud metallic tinkling, and a bruit de souffle, or sound like the blowing of a pair of bellows, or a sawing noise, like bronchial respiration, accompanying the systole of the heart. In the early stages, the breathing is not so difficult as in Pericarditis; but if the auriculo-ventricular valves are thickened, it becomes distressing. Sometimes the whole of the membrane is thickened; in other cases the lesion is limited; in others, the abnormal growth forms a cardiac Polypus, which may grow to an enormous size. The legs are usually cold.
Pathology.—The endocardium, although a serous membrane, is mixed with fibrous elastic tissue at its valvular reduplications, which accounts for the disease being so frequently associated with rheumatism, and for the morbid appearances more commonly witnessed in the valvular structure of the heart than elsewhere. The natural result of inflammation in this, as in other serous membranes, is the effusion of lymph, and consequent thickening, which sometimes interferes with the play of the valves, or narrows the auriculo-ventricular openings, thus producing the bellows-sound which has been described as one of the chief symptoms. The inflammation may extend to the muscular substance of the heart, which becomes darkened in color and easily broken down; while in some cases large quantities of fibrin are thrown out, which quite block up the auriculo-ventricular openings and orifices of the large blood-vessels. To Endocarditis may also be traced Tumors and Polypi, as well as Hypertrophy and Dilatation. Abscess in the walls of the heart has also been observed as a consequence of Endocarditis.