Cardiovascular pathology in hyperlipoproteinemia: Anatomic observations in 42 necropsy patients with normal or abnormal serum lipoprotein patterns

Abstract

Certain clinical and cardiovascular necropsy findings are described in 28 patients with known hyperlipoproteinemia and 14 patients known to have a normal lipoprotein pattern. Of the 42 patients, 28 had symptomatic ischemic heart disease: 20 of these had hyperlipoproteinemia (9 type II, 2 type III, and 9 type IV), and 8 had a normal lipoprotein pattern. The average age at death in the 20 patients with hyperlipoproteinemia and symptomatic ischemic heart disease was 48 years, and in the 8 with a normal lipoprotein pattern and ischemic heart disease, 46 years. The degree of coronary arterial luminal narrowing was severe in all patients with ischemic heart disease whether their lipoprotein pattern was normal or abnormal. In all 28 patients with symptomatic ischemic heart disease, the lumen of at least 1 of the 3 major coronary arteries was narrowed more than 75 percent by old atherosclerotic plaques, and in 25 of these all 3 major coronary arteries were narrowed to this extent. With the exception of 1 of the 2 patients with a type III pattern, the composition of the coronary atherosclerotic plaques was similar among patients with type II, III and IV hyperlipoproteinemia and among those with a normal lipoprotein pattern. Attention is called to the unique type of valvular aortic stenosis that frequently develops in the homozygote with a type II pattern and also to the reversed distribution of the aortic atherosclerotic plaquing in the homozygote with a type II pattern. In these patients the amount of plaquing appears to be greater in the ascending than in the abdominal portion of the aorta. Lipid plaques were observed on left atrial endocardium in 2 patients: One had type I hyperlipoproteinemia without associated coronary or aortic atherosclerosis; the second had a type III pattern with extensive coronary and aortic atherosclerosis. These left atrial endocardial lipid deposits may be unique to these hyperlipoproteinemias. In conclusion, it appears clear that atherosclerosis is accelerated or occurs prematurely in patients with type II, III and IV hyperlipoproteinemia, but that hyperlipoproteinemia is not a prerequisite for premature development of severe atherosclerosis.