The aim of the study was to evaluate the relationship between phytosterols, oxyphytosterols, and other
markers of cholesterol metabolism and concomitant coronary artery disease (CAD) in patients with severe aortic stenosis who were scheduled for elective aortic valve replacement.
Markers of cholesterol metabolism (plant sterols and cholestanol as markers of cholesterol absorption
and lathosterol as an indicator of cholesterol synthesis) and oxyphytosterols were determined in plasma
and aortic valve tissue from 104 consecutive patients with severe aortic stenosis (n = 68 statin treatment;
n = 36 no statin treatment) using gas chromatography-flame ionization and mass spectrometry. The
extent of CAD was determined by coronary angiography prior to aortic valve replacement.
Patients treated with statins were characterized by lower plasma cholesterol, cholestanol, and lathosterol concentrations. However, statin treatment did not affect the sterol concentrations in cardiovascular
tissue. The ratio of campesterol-to-cholesterol was increased by 0.46 ± 0.34 lg/mg (26.0%) in plasma of
patients with CAD. The absolute values for the cholesterol absorption markers sitosterol and campesterol
were increased by 18.18 ± 11.59 ng/mg (38.8%) and 11.40 ± 8.69 ng/mg (30.4%) in the tissues from
patients with documented CAD compared to those without concomitant CAD. Campesterol oxides were
increased by 0.06 ± 0.02 ng/mg (17.1%) in the aortic valve cusps and oxidized sitosterol-to-cholesterol
ratios were up-regulated by 0.35 ± 0.2 ng/mg (22.7%) in the plasma of patients with CAD. Of note, neither
cholestanol nor the ratio of cholestanol-to-cholesterol was associated with CAD.
Patients with concomitant CAD are characterized by increased deposition of plant sterols, but not cholestanol in aortic valve tissue. Moreover, patients with concomitant CAD were characterized by increased
oxyphytosterol concentrations in plasma and aortic valve cusps.