Definition:—A tumor caused by a localized dilatation of a blood-vessel. It may involve an artery, a vein or both conjointly.

There are three varieties of aneurism. They are the fusiform, in which the portion of the blood-vessel involved is evenly dilated, and the sacculated, in which an area not including the whole circumference of the blood-vessel is dilated. A sacculated aneurism may be found upon a portion of a fusiform aneurism. The third variety is the dissecting aneurism, in which the blood has dissected its way between the coats of the blood-vessel.

Occurrence:—The order in frequency of occurrence is as follows: Thoracic aorta, ascending and transverse portions, popliteal, carotid, subclavian, innominate, axillary, abdominal aorta. Small arteries are also involved, those in the brain, lungs and heart giving rise to serious conditions.

Etiology:—Aneurisms occur most frequently in the active period of life when the vascular system begins to be weakened and while yet the full tide of life's activities is on. Strain, both physical and emotional, are consequently factors in the etiology of aneurism. Men are more frequently affected than women. Anything that weakens the wall of the blood-vessel may cause aneurism, and syphilis, alcohol, rheumatism and gout are therefore responsible for many cases. Parasitic embolism may give rise to aneurism and trauma may be followed by it.

Symptomatology:—Twenty per cent of aneurisms give rise to no symptoms. Inspection may reveal a tumor, which may be seen to pulsate. Palpation may confirm these findings. The pulsations will be found to be synchronous with the heart-beats. If possible to apply both hands to the tumor they will tend to separate with each pulsation. If pressure is applied to the artery on the side of the tumor proximal to the heart the size of the tumor is lessened. If pressure is applied to the artery on the side of the tumor distal to the heart the size of the tumor is increased. Auscultation will reveal a bruit in the tumor and in the artery beyond it in the majority of cases. Percussion in thoracic and abdominal aneurisms may reveal an increased area of dulness according to the size and location of the tumor.

Pain is a common and early symptom of aneurism, and is due to pressure on nerves. It is especially severe when the tumor erodes bone as the vertebral bodies in the case of thoracic or abdominal aneurism.

There are certain signs and symptoms of aneurism dependent on the size and location of the tumor. In the extremities oedema and gangrene occur, the former constantly after the aneurism has reached a certain size. Aneurism of the vessels of the brain may cause hemiplegia, facial paralysis, blindness, ptosis, strabismus, and deafness by pressure on the cranial nerves.

In the thorax the tumor may compress the oesophagus, causing dysphagia; the trachea, causing the symptom known as tracheal tugging; the thoracic duct, interfering with nutrition; the recurrent laryngeal nerve, causing a characteristic and persistent brassy cough; the phrenic nerve, causing hiccough; the sympathetic ganglia, causing capillary congestion; with pressure on the left common carotid or the innominate, the radial pulse of the side affected will be delayed.

Aneurism of the abdominal aorta may cause pain by eroding the vertebrae; subsequently numbness and tingling in the legs may develop. Paraplegia may be the ultimate consequence.

Disorders of digestion, especially vomiting and pain, are usual. In the epigastric region a distinct tumor is generally visible and palpable. Pulsation of the abdominal aorta must not be mistaken for aneurism. A systolic murmur is usually heard, frequently best elicited behind, near the spinal column.

Diagnosis:—Aneurisms, visible or palpable, are differentiated from other pulsating tumors by being expansile in the majority of cases. The factors of pain and functional disturbance must be considered in relation to other symptoms and usually a diagnosis of aneurism may be arrived at. Rheumatism is sometimes simulated by popliteal aneurisms, and girdle pains of tabes dorsalis by pressure of an abdominal aneurism on the spinal nerves near the intervertebral foramina. The pain of aneurism is more constant and not so variable in intensity. Tumors of the mediastinum usually produce more severe symptoms, as tracheal stenosis rather than tugging, and recurrent laryngeal paralysis as compared to irritation as seen in the brassy cough.

Treatment:—The first essential in the treatment is rest; absolute physical rest, retaining a passive condition of the muscular system as long as possible, at times without any exercise, or even movement. At the same time mental quiet must be maintained and an entire absence of mental exercise, if possible, as well as avoidance of excitement, agitation, worry, anger or grief. All this is done to preserve the least possible muscular effort on the part of the heart, in maintaining the circulation and to slow its action and lessen its force. The main object of the medical treatment is to solidify the contents of the sac through coagulation of the blood and solidification of its fibrin. The old school of physicians accomplished these results by depletion and restriction of the diet.

The use of veratrum viride to slow and steady the heart's action is authorized, with gelsemium to reduce nerve tension, arterial tonus and nerve irritation. The bromids will accomplish the same results and lessen muscular irritability when that exists. The potassium bromid is the best for this purpose if there is no undue sensitiveness or irritation of the stomach. Aconite is an important remedy at this time in its influence upon the entire circulatory apparatus. The potassium iodid has the confidence of the profession in its influence upon the major portion of the conditions involved. It lessens pain, diminishes both the tension of the sac and general arterial tonus and increases the contractile power of the muscular structures which is usually lessened. The influence of the remedy in syphilitics is universally recognized.

Ergot is of some service. We would use it in small doses, in conjunction with similar doses of hydrastin, giving this latter agent short of any active tonic or stimulating influence it might exercise.

The electrical method of consolidation is now employed in sacculated aneurism. From five to ten or more feet of fine gold wire, thoroughly sterilized, are introduced into the sac through an insulated needle. The external end of the wire is attached to the positive electrode of a galvanic battery and the negative electrode is applied to the back, and from five to fifteen milliamperes of electricity are turned on. The current is allowed to pass through the wire from half an hour to an hour. The wire is then clipped close to the wall of the sac, and the tip is caused to be withdrawn within the sac. This, followed by absolute quiet, results in speedy and quite satisfactory consolidation. The condition of the walls, however, may be such that other sacs will quickly form.

The Eclectic Practice of Medicine with especial reference to the Treatment of Disease, 1910, was written by Finley Ellingwood, M.D.