According to the best authorities on medicine, this disease is the result of infective processes; but when the student desires to know what infective process has brought it about, he will learn that it has been caused by some other disease established by an infective process, and he gets nowhere in his investigation in regard to the origin of the disease.

If the student will bear in mind that, primarily, there is but one source of infection, and that is in the alimentary canal, he will have no trouble in tracing all diseases back to their own origin. Toxin poisoning from putrefaction in the intestine, plus constitutional diathesis, or plus organic diathesis, supplies the origin of all organic diseases, which should be called affections. Infection or toxemia starts a process known as rheumatism. The same identical cause will develop pericarditis in a subject who has a cardiac diathesis; and this is the source of the infection that causes this disease.

Etiology

It is very doubtful if this disease is ever anything more than symptomatic. A wound in the chest involving the pericardium, and an inflammation of the pleura, may extend to the pericardium; but when this is true it is symptomatic; hence, barring injuries to the pericardium, diseases of this character must be symptomatic and due to infection through the blood. Injuries have been found to come from passage of foreign bodies in the trachea, such as needles, pins, or small pieces of bone which have found their way through the esophagus. These are rare, however.

The disease is common at any age. Children with scarlet fever, who are badly cared for, are liable to develop this disease. The characteristic form in anemia is acute fibrinous pericarditis.

Symptoms

The principal symptoms are precordial oppression. People with this disease will want to sleep with the head high--with several pillows--especially if there is an effusion in the sac. Pain is never very intense, and is usually more marked in the early stages. The most pronounced case that has ever come under my observation was that of a child five years of age. She had scarlet fever. After the rash had disappeared and she appeared to be convalescing, she lingered on and did not improve satisfactorily. She sat up in bed, not being able to lie down on account of the difficult breathing. When I was called I found radical dullness over the region of the heart, and gave it as my opinion that there was an effusion in the pericardium; which, at my next visit, I withdrew with an aspirator. The fluid withdrawn appeared to be pure blood. However, it could not have been. It was probably a little thinner than normal blood. I removed twelve ounces, and the child made a good recovery. This was a case of hemorrhagic pericarditis--the only case I have ever seen.

Pericarditis with Effusion

The material thrown into the pleura is usually of the character of serum. The symptoms generally are slight: a shortness of breath and an increasing pallor. Seemingly without symptoms to justify it, the physician will find a pronounced accumulation. Great restlessness is one of the principal symptoms; and where the accumulation is large, relief must be procured by aspiration, or the patient will be worn out from difficult breathing and lack of sleep.