ELEVATED PLASMA ENDOTHELIN-1 LEVELS IN SICKLE-CELL-ANEMIA - RELATIONSHIPS TO OXYGEN-SATURATION AND LEFT-VENTRICULAR HYPERTROPHY

Endothelin-1 (Et-1) is a vasoconstrictor produced by endothelial and v ascular smooth muscle cells in response to hypoxia, which induces hype rtrophy in cultured cardiac myocytes, We measured plasma Et-1 levels a nd left ventricular dimensions in 13 patients with sickle cell anemia (SCD) and in 12 African-American controls ages 16-29 years. Endothelin -l concentrations are significantly higher in SCD subjects than contro ls (10.6 +/- 1.9 vs. 3.0 +/- 1.3 pmol/L). There was a negative correla tion between oxygen saturation and Et-1 levels in SCD patients (r = -0 .71, P = 0.01). SCD subjects have more dilated and hypertrophied heart s corrected for body surface area than controls as evidenced by signif icant increases in left ventricular end diastolic dimension (31 +/- 0. 8 vs. 24 +/- 0.9 mm/m(2), P < 0.001), left ventricular end systolic di mension (20 +/- 0.9 vs. 16 +/- 0.8 mm/m2, P = 0.002), left ventricular posterior wall thickness (5.0 +/- 0.1 vs. 4.0 +/- 0.1 mm/m(2), P< 0.0 01), and left ventricular mass (125 +/- 7.2 vs, 69 +/- 5.1 g/m(2), P < 0.001). The index of left ventricular function, the shortening fracti on, was not different between groups (34 +/- 1.2% in SCD vs, 35 +/- 1. 5% in controls). The correlation between left ventricular mass and lev els of Et-1 in SCD subjects was not significant (r = 0.47, P = 0.121), Am, J, Hematol. 58:195-199, 1998, (C) 1998 Wiley-Liss, Inc.