Clinical Diagnosis of Dissecting Aneurysm of the Aorta

Dissecting aneurysm of the aorta, while not extraordinarily frequent , is not an uncommon occurrence. Over 300 cases have been reported in the literature, and there are, no doubt, many cases which have not found their way into print. The diagnosis of the condition during life is, however, extremely rare, only eight cases, including the one about to be presented, having been recorded as definitely diagnosed clinically. Swaine, in 1855, was the first to make. a correct diagnosis. An explanation of the infrequency of the diagnosis of dissecting aneurysms is offered by Shennan3 in a recently published monograph in which he has thoroughly discussed the condition. Although the disease is so overwhelmingly spectacular in most instances, he states that the clinical picture presented is one of great variety. He has found that the only feature common to all the cases he has reviewed is the suddenness of onset, the affliction usually attacking an individual without previous indication of heart disease. This onset appears as a "feeling of something giving way in the thorax, with sensations of choking and strangling" and a fear of impending death. The next most common symptom is sudden, severe pain in the chest or abdomen, which may occasionally be accompanied by pain in the side of the head and neck or extending to the extremities. Where the pain is of this intense nature there usually follows collapse and suddenly developing dyspnea, which may be superseded by loss of consciousness and death. Cyanosis due to venous obstruction is found in all cases in which the ascending aorta is involved. Other symptoms of less frequency are pain in the abdo-pain on the side of the head and neck, and leukocytosis without fever are seen only in individual cases. Shennan concludes that the principal factor predisposing to rupture of the aorta and dissecting aneurysm is a degeneration of the tunica media, due in most cases to a "selective action of the