Autor: |
Guillaume, Hekimian, Stephanie, Passefort, Liliane, Louedec, Xavier, Houard, Marie-Paule, Jacob, Alec, Vahanian, Jean-Bapstiste, Michel, David, Messika-Zeitoun |
Rok vydání: |
2009 |
Předmět: |
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Zdroj: |
The Journal of heart valve disease. 18(2) |
ISSN: |
0966-8519 |
Popis: |
Recent data have shown that aortic valve stenosis (AS) is an active and highly regulated process which shares similarities with atherosclerosis. However, AS cannot be considered as a purely atherosclerotic phenomenon, and a hypercholesterolemic rabbit model might not be fully representative of human AS pathophysiology.Twenty-eight New Zealand White rabbits were assigned to three groups: group 1 (no dietary supplement for three months); group 2 (0.3% cholesterol-enriched-diet + 50,000 IU/day vitamin D2 for six months); and group 3 (1% cholesterol-enriched-diet + vitamin D2 for three months). The peak aortic gradient and permeability index (outflow tract/aortic velocity-time-integral) were assessed, as well as calcium staining within the aortic valve and ascending aorta.AS hemodynamic severity was not different among the groups. The peak gradient was 4 +/- 2 mmHg at baseline, 4 +/- 2 mmHg at three months in controls, 4 +/- 1 mmHg at three months and 6 +/-3 mmHg at six months in group 2, and 4 +/- 1 mmHg at three months in group 3 (p = NS). The permeability index was 64 +/- 7 at baseline, 60 +/- 12 at three months in controls, 63 +/- 14 at three months and 58 +/- 12 at six months in group 2, and 60 +/- 5 at three months in group 3 (p = NS). The aortic valve of cholesterol-enriched-diet rabbits was thickened but not calcified, whereas the ascending aorta was both thickened and calcified.When using a hypercholesterolemic rabbit model plus vitamin D2, no adverse hemodynamic effect or aortic valve calcification was observed, despite a high-level and prolonged cholesterol-regimen supplementation. These results raise questions with regard to the extrapolation of this animal model to humans. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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