Lower serum calcium levels are associated with greater calcium hydroxyapatite deposition in native aortic valves of male patients with severe calcific aortic stenosis.
OBJECTIVE
The study aim was to evaluate the relationship between serum calcium levels and the degree of calcification found in stenotic aortic valves.


METHODS
Using atomic absorption spectroscopy, the hydroxyapatite content of 228 excised human stenotic aortic valves was determined and expressed as a percentage of valve mass. Left heart catheterization preceded valve replacement. In addition, serum levels of calcium and creatinine were determined before native calcific aortic valve excision.


RESULTS
Valves from male patients contained more hydroxyapatite than those of female patients (26 +/- 9 versus 22 +/- 9 mass%; p < 0.001). Patients presenting with lower serum calcium levels showed a slight trend towards higher levels of valve calcification (r = -0.15, p = 0.026), but this association appeared only within the subgroup of male patients. Male patients with lowest serum calcium levels displayed greatest valvular hydroxyapatite deposition (1st calcium tertiary: 29.5 +/- 8.9 mass% versus 2nd calcium tertiary 26.4 +/- 7.8 mass% versus 3rd calcium tertiary 21.4 +/- 8.9 mass%; n = 122; p = 0.001; r = -0.25; p = 0.006). This association was even more distinct in male patients with normal serum creatinine levels. Furthermore, serum calcium was inversely and significantly associated with serum C-reactive protein in male patients (r = - 0.34; p < 0.001).


CONCLUSIONS
Serum calcium levels appear to be inversely related to valve calcification in patients with severe calcific aortic stenosis (AS). This finding indicates the importance of systemic calcium metabolism in calcific AS, independent of manifest disorders of calcium metabolism or renal function. Interestingly, this association was evident only in male patients, suggesting a gender-dependent pathogenesis.
Ortlepp
Jan R
JR
Clinic for Interdisciplinary Intermediate Care and Medical Clinic I, University Hospital of Aachen, Germany. jrortlepp@ukaachen.de
Pillich
Manuela
M
Schmitz
Fabian
F
Mevissen
Vera
V
Koos
Ralf
R
Weiss
Stefan
S
Stork
Ludwig
L
Dronskowski
Richard
R
Langebartels
Georg
G
Autschbach
Rüdiger
R
Brandenburg
Vincent
V
Woodruff
Seth
S
Kaden
Jens J
JJ
Hoffmann
Rainer
R
D000368:Aged; D001021:Aortic Valve / Q000737:chemistry / Q000378:metabolism*; D001024:Aortic Valve Stenosis / Q000378:metabolism*; D002097:C-Reactive Protein / Q000032:analysis; D002114:Calcinosis / Q000378:metabolism*; D002118:Calcium / Q000097:blood*; D017886:Durapatite / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D012737:Sex Factors
D002097:C-Reactive Protein; D017886:Durapatite; D002118:Calcium