The symptoms which have been already enumerated in the table given under the head of hypertrophy are mainly these: Loss of appetite, spirit and endurance; faintness and difficulty of breathing on the slightest exertion; habitual coldness with a tendency to dropsy of the extremities; loss of control over the extremities when walked or trotted far; venous pulsation in the jugulars; heart’s impulse weak and undulatory or tremulous, or under exertion tumultuous or palpitating; murmur often present with the first sound; the first or more commonly the second sound may be doubled; pulse small, weak, irregular, and often intermittent, and frequently livid spots in the nasal mucous membrane. Paroxysms of unsteady gait from irregular circulation in the brain is frequent, and Dyer asserts that he has repeatedly seen blindness as a result of this condition.
In treatment the main purpose should be to put a stop to the cause of the disease before it has been developed to a dangerous extent. When the malady is manifested by the symptoms above enumerated the subject is rendered permanently unfit for service and will probably die suddenly under some slight exertion. Fattening animals in a condition of quietude will often lay on flesh for an indefinite length of time notwithstanding that the heart is considerably dilated. (See note on digitalis, strophanthus and arsenious acid in dilated heart, under the head of hypertrophy). To relieve the asthmatic attacks attending on an overtaxed heart Zuill strongly recommends the combination of iodide of potassium, digitalis, nux vomica and coca. But heart tonics are often much more affective after the bowels and portal system have been unloaded by a laxative.
INFLAMMATIONS IN THE HEART.
These are among the most common diseases of this organ and moreover lead to many of the changes in structure to be hereafter noticed so that it is convenient to treat of them here. According to their relative frequency they may be ranged:—1st. Inflammation of the external covering of the heart—pericarditis; 2d. Inflammation of the internal lining membrane of the heart—endocarditis; and 3d. Inflammation of the muscular substance of the heart—carditis.
PERICARDITIS.
Definition. Frequency in different genera. Causes, rheumatic, traumatism, extension from pleurisy. Unwholesome buildings and localities, debility. Symptoms, chill, reaction, pleuritic symptoms, hyperthermia, tenderness behind left elbow only, friction sound synchronous with heart beat, later it is lost and heart sounds are muffled, increased area of dulness on percussion, oppressed breathing, venous pulse, patient statant, little fever in chronic cases. Traumatism from the stomach, digestive disorder, grunting, dropsy under the sternum with little fever at first. Lesions, as in pleurisy, obliteration of pericardial sac. In traumatism from stomach the foreign body is formed in the cardiac end of a band of lymph extending to the reticulum. Treatment, in chill, after reaction, medicinal measures as in pleurisy, local applications to the region of the heart. Paracentesis, insertion of needle, antiseptic precautions. Chronic pericarditis in oxen.
Definition. Inflammation of the strong fibro-serous sac in which the heart is contained and which is reflected on the muscular substance of that organ so as to form its external covering.
This is the most common inflammatory disease of the heart and has been met with more frequently in horses and cattle than in the smaller quadrupeds.
Causes. It frequently coincides with or follows other diseases such as influenza, pleuro-pneumonia and above all rheumatism. In cattle and goats wounds from sharp pointed bodies, (needles, pins, nails, etc.), which have been swallowed with the food and have passed through the walls of the second stomach, the diaphragm and pleura to the heart constitute a frequent cause in cattle. The pericardium has been punctured by a fractured rib and has been implicated in inflammation attendant on an abscess or other lesion in the walls of the chest. Besides these the general influences which cause uncomplicated attacks of the disease are the same as those producing pleurisy, peritonitis, rheumatism and inflammation of serous membranes generally. These are sudden changes from heat to cold, cold winds, cold draughts, drenching, chilling rains in animals already overheated and exhausted, or prolonged exposure in severe weather, in low states of the system. Leblanc justly remarks that “with the morbid influences which appear specific, there often coincide intemperate seasons, badly arranged buildings, a want of sufficient attention to the conditions of health, and in the case of herbivora, wet, cold, and badly exposed pastures.” In other words whatever deteriorates the health and vitality predisposes.
Symptoms. These are less characteristic than in man owing to the smaller portion of the heart exposed, but they are usually marked enough to permit a recognition of the disease. Acute form. The affection is ushered in by chill, general fever, hyperthermia, (103° to 104°), staring coat, hot, dry mouth, dilated nostrils, excited, difficult breathing, double lifting of the flank with each expiration, the existence of a prominent ridge from the lower end of the last ribs along the flank to the outer angle of the hip bone, as in pleurisy, pinched, anxious expression of countenance, fixed eyes, accelerated, full, hard and often wiry pulse, and tenderness when the ribs behind the left elbow are pinched or struck. The same tenderness is noticed particularly in the ox and smaller quadrupeds when pressure or compression is made beneath the breast bone. Auscultation over the lower ends of the fifth and sixth ribs and their cartilages detects a friction or rubbing sound in the early stages and until liquid has been thrown out into the pericardial sac. This sound may be at first the finest possible creaking, afterward increasing to a distinct rubbing, is synchronous with the beat of the heart, and usually with the first sound. It is distinguished from the friction sound of pleurisy in occurring rythmically with the sounds of the heart and not with those of breathing, and from sounds produced in the interior of the heart by its absence when auscultation is made over the carotid or other large artery. This friction sound is lost when serous effusion takes place into the pericardium, but reappears when the liquid is absorbed in the process of recovery. Until effusion takes place the impulse of the heart is strong, often irregular, in force, and sometimes accompanied by a purring tremor or, according to Leblanc, a metallic tinkle.