Endothelin-1 and nitric oxide levels in patients with mitral annulus calcification.

Mitral annulus calcification (MAC) is a chronic degenerative noninflammatory process. The goal of this study was to determine endothelin-1 (ET-1) and nitric oxide (NOx) levels in patients with MAC and compare them with those in normal subjects. The study group included 39 patients [26 females (66%), age, 63 +/- 8 years] with MAC and 20 [11 females (55%), age, 61 +/- 7 years] healthy subjects. The patients were divided into two subgroups, group A with severe MAC and group B with mild MAC, according to the severity of the MAC. Plasma ET-1 levels were higher and NOx levels were lower in patients than controls [(6.5 +/- 5.6 pg/mL vs 3.7 +/- 2.9 pg/mL for ET-1 and 35.0 +/- 10.6 micromol/L vs 42.3 +/- 9.9 micromol/L for NOx; P < 0.05 for both)]. In the subgroups, ET-1 levels were higher in group A than group B (8.65 +/- 6.84 pg/mL vs 4.74 +/- 3.45 pg/mL, P < 0.05) and the control group (8.65 +/- 6.84 pg/mL vs 3.70 +/- 2.88 pg/mL, P < 0.05). There was no difference between group B and the control group. Plasma NOx levels were significantly decreased in group A compared to controls (32.22 +/- 11.88 micromol/L vs 42.25 +/- 9.99 micromol/L, P < 0.05). However, no significant difference was observed between group B (37.38 +/- 9.06 micromol/L) and the other groups. Diabetes mellitus, coronary artery disease, and dyslipidemia were significantly associated with ET-1 levels. However, this association was not observed for NOx. In conclusion, patients with MAC have increased ET-1 and decreased NOx levels. This seems to be more prominent in patients with severe MAC.