[Phosphocalcium metabolism in patients with calcified valvular bioprosthesis].
Calcium and gla-protein content are increased in the calcifications of cardiac bioprostheses. Such calcifications are more frequent during growth, pregnancy and renal failure when bone gla-protein levels are elevated. We investigated whether bone gla-protein and other markers of calcium metabolism play a role in bioprostheses calcifications. Forty-seven patients were separated into 2 groups according to the presence (group A, n = 9) or absence (group B, n = 38) of bioprostheses calcifications, as assessed by echo-doppler and surgery. Plasma levels of calcium, phosphorus, magnesium, creatinine and alkaline phosphatases were measured by standard laboratory methods, parathormone and those of bone gla-protein by specific radioimmunoassays. Results (mean +/- SEM) were compared (group A versus group B, P < 0.01) using Student's test and one-factor variance analysis (ANOVA). Age was similar in both group (53 +/- 12.9 vs 50 +/- 12.3 yrs), whereas duration of implant was greater in group A (104 +/- 12.4 vs 66 +/- 6.5 months, P < 0.01). No statistically significant difference was found between group A and B concerning biochemical and/or hormonal markers of calcium metabolism. These negative results merit to be discussed, and further studies will be needed to explore the potential role of circulating bone gla-protein in bioprostheses calcifications.
Farge
D
D
Service de Médecine interne et Pathologie vasculaire, Hôpital Saint-Louis, Paris.
Shen
M
M
Castaldo
F
F
Gardin
J P
JP
Carpentier
S
S
Cambillau
M
M
Puaud
A C
AC
Carpentier
A
A
D001021:Aortic Valve; D001705:Bioprosthesis / Q000009:adverse effects*; D002114:Calcinosis / Q000209:etiology / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve; D010758:Phosphorus / Q000378:metabolism*; D011475:Prosthesis Failure
D010758:Phosphorus; D002118:Calcium
Métabolisme phosphocalcique chez les malades ayant une bioprothèse valvulaire calcifiée.