[Calcified aortal stenosis and osteoporosis: bone metabolism of systemic calcium metabolism in the elderly]

AIM

To examine bone tissue, systemic calcium metabolism and bone remodeling in patients with calcified aortal stenosis of degenerative origin (DAS).

MATERIAL AND METHODS

The examination of 310 patients (mean age 73.2 years) was made with application of questioning, echocardiography, double energetic x-ray absorptionmetry, measurements of C-telopeptides, osteocalcin, vitamin D, parathyroid hormone with solid phase enzyme immunoassay.

RESULTS

Bone tissue mineral density (BTMD) was abnormal in 71% of examinees (osteopenia--40%, osteoporosis--31%). Vitamin D concentration under 50 nmol/l was in 76.3%, parathyroid hormone elevated above 100 pg/ml in 15.8% patients.

CONCLUSION

The severity of lumbar spine affection depended on severity of calcinosis of aortic valve, was associated with lowering of osteosynthetic activity and was not associated with the presence of osteoporosis risk factors, constitutional parameters, calcium metabolism changes. This suggests the existance of a special form of BTMD disorder in elderly patients with aortal stenosis.

Presence of oxidized low density lipoprotein in nonrheumatic stenotic aortic valves

The aim of the present study was to analyze if LDL particles trapped in stenotic aortic valve tissue undergo oxidative modification. Degenerative aortic stenosis affects >3% of the population >75 years of age in the Western world. Recent studies have revealed the presence of a chronic inflammatory process similar to what has been described in other degenerative diseases such as atherosclerosis. However, the underlying disease mechanisms of degenerative aortic stenosis still remain largely unknown. Six tricuspid stenotic valves, obtained at valve replacement, were compared with 3 control valves collected from hearts taken out during transplantation. The stenotic valves and the control valves were examined by immunohistochemistry, using antibodies against apoB, 4-hydroxynonenal-modified LDL, leukocytes, and HLA-DR. All valves were also stained with oil red O for neutral lipids. Extracellular neutral lipids were found in all stenotic valves, extending from the bases along the fibrosa layer. This lipid colocalized with apoB- and 4-hydroxynonenal-modified LDL immunoreactivity. 4-Hydroxynonenal-modified LDLs were present around calcium deposits, subendothelially, and in the deeper layer of the fibrosa. There was also a colocalization with macrophages, T lymphocytes, and HLA-DR expression. Control valves had a thin area of neutral lipid accumulation, a small amount of apoB, but no signs of inflammation. A distinct colocalization between oxidized LDLs, T-lymphocyte accumulation, and calcium deposits suggests that oxidized lipids may play a role in the disease process.