The implications of patterns of occlusion in arteriosclerosis

Abstract

W ith the advent of operative approaches to the arteries came the necessity for an exact localization of the lesions of arteriosclerosis. So far, more of such data are available for the lower extremities than for other parts of the body. As more information is gained, it becomes apparent that certain patterns of the arterial involvement may be expected in certain clinical situations. As examples, I may cite the youth of patients with occlusion commencing in the aortic bifurcation, the tendency for diffuse arterial involvement in diabetes, and the association of pulmonary arteriosclerosis with previous pulmonary embolism for hypertension. These associations strongly suggest that arteriosclerosis is not a disease per se, but rather the end result of a variety of causative disease states. There are additional indications that some sites of initial involvement are associated with relative discreteness of disease, others with diffuseness. This, in turn, carries an implication of varying prognosis, since diffuse disease involves many areas in the body, and also shows a tendency to a more rapid progression of disease. I will attetipt in this paper to review what is known of the locations of arteriosclerosis, with some consideration of the means of recognizing the lesions in these places, and I will mention the varying prognoses which attach to different sites of involvement. Anatomic factors in the efects of occlusion. Peculiarities in the anatomic pattern of the arteries, particularly with respect to their anastomotic connections, are important in varying the effects of occlusion from one site to another, and between individuals as well. Ischemia of a limb often fails to follow a glove or stocking distribution because of a relative circumscription that exists for the blood supply to muscle, nerve, and even to portions of the integument.ga For this reason, ischemia may be limited to parts of an extremity, as may be seen in interruption to the vessels of a viscus in the abdominal cavity. Thus, because of occlusion of the hypogastric artery, claudication often persists in the buttock after successful restoration of flow to the rest of the limb. Similarly, a neuritis or a cutaneous infarct may be due to an occlusion of the nutrient artery to those parts quite out of proportion to the vascular status of the limb as a whole. Unexpectedly severe ischemia may occur in organs with multiple sources of supply if the anastomoses between these sources are imperfect. -A detailed consideration