Autopsy of a 78-year-old man demonstrates decreased left ventricular cavity size and a sigmoid-shaped ventricular septum. Light microscopy shows increased collagen content within the ventricular wall. Some myocardial cells also have brownish perinuclear cytoplasmic inclusions. The changes described are most consistent with which of the following conditions?

Question

Autopsy of a 78-year-old man demonstrates decreased left ventricular cavity size and a sigmoid-shaped ventricular septum.  Light microscopy shows increased collagen content within the ventricular wall.  Some myocardial cells also have brownish perinuclear cytoplasmic inclusions.  The changes described are most consistent with which of the following conditions?

Quizplus · Accepted Answer

11ec160b_3c83_6c96_9249_6b87a65e20e0_MD0001_00 The morphologic changes described are consistent with normal aging of the heart. Aging is associated with decreased left ventricular chamber size, particularly in the apex-to-base dimension. This decrease in chamber length causes the ventricular septum to acquire a sigmoid shape, with the basilar portion bulging into the left ventricular outflow tract. Atrophy of the myocardium results in increased interstitial connective tissue, often with concomitant extracellular amyloid deposition. Within the cardiomyocytes, there is a progressive accumulation of cytoplasmic granules containing brownish lipofuscin pigment (the result of indigestible byproducts of subcellular membrane lipid oxidation). (Choice A) Dilated cardiomyopathy causes an increase in the left ventricular chamber size. There is an increased risk of mural thrombi with this condition due to contractile dysfunction. (Choice B) Chronic hemolytic anemia may result in the formation of hemosiderin granules containing excess iron inside cardiac myocytes (hemosiderosis), which can be visualized with Prussian-blue stain. Excessive deposition of iron within the myocytes usually leads to dilated or restrictive cardiomyopathy. (Choice C) Hypertrophic cardiomyopathy (idiopathic hypertrophic subaortic stenosis) causes asymmetric septal hypertrophy with disproportionate thickening of the ventricular septum compared to the left ventricular free wall. Microscopic examination shows extreme myocyte hypertrophy, disorganized myocyte bundles, and myofiber disarray. (Choice D) Chronic ischemic heart disease tends to result in progressive congestive heart failure and ventricular dilation. Histologically, the major findings are diffuse subendocardial vacuolization and fibrosis. (Choice E) Long-standing hypertension results in hypertensive heart disease. Although left ventricular chamber size may be reduced in this condition, the major morphologic change is concentric left ventricular hypertrophy. Educational objective: Normal morphological changes in the aging heart include a decrease in left ventricular chamber apex-to-base dimension, development of a sigmoid-shaped ventricular septum, myocardial atrophy with increased collagen deposition, and accumulation of cytoplasmic lipofuscin pigment within cardiomyocytes.

Autopsy of a 78-Year-Old Man Demonstrates Decreased Left Ventricular Cavity