Thrombomodulin levels in asymptomatic familial hypercholesterolemia.

: In order to ascertain whether young asymptomatic patients with heterozygous familial hypercholesterolemia (FH) but without clinical signs of atherosclerosis have increased plasma thrombomodulin (TM) levels expressing early endothelial damage, we determined TM in 23 heterozygous FH subjects (aged 28-44 years, x: 32 +/- 6) and in a well matched control group (CG). In addition, carotid Doppler ultrasonography was done in all the patients and controls in order to assess the state of the vascular tree. Results show a tendency for FH subjects to have higher TM values than the CG (37.8 +/- 14.2 ng/ml vs. 30.1 +/- 11.2 ng/ml), although the differences are not statistically significant. When taken together the results of TM and carotid ultrasound, the sensitivity and specificity of the former were only 66% and 80%, respectively. The fact that only 66% of the FH patients with atherosclerotic injury had high TM values eliminates the possibility of using this as an early marker of atherosclerosis in FH individuals.