Pathogenesis of diffuse intimal thickening (DIT) in aortas and coronary arteries of 2 1 2-year-old minature pigs

Lesions resembling diffuse intimal thickening (DIT) in morphology are reported in the left anterior descending coronary arteries and aortas of 2 1 2-year-old miniature swine. The lesions are similar in composition and location to those previously described under a variety of names in swine, either large or miniature. The lesions are intermediate in size when compared with those of younger and older swine, and when all the data are seen together, a picture emerges of gradually enlarging musculoelastic lesions which eventually assume a double or triple-layered structure. The lesions are mostly focal, and are most pronounced in the abdominal aortas where their rather constant localization to proximal posterior and distal anterior walls suggests thay they are caused in part by hemodynamic stresses.