Oxidative stress and cytochrome P450-dependent liver metabolism decrease in patients with acquired valvular heart disease

Aim of investigation. The evaluation of oxidative stress and liver monooxygenase function in patients with acquired valvular heart disease (AVHD) after cardiac surgery. Methods. Ninety-seven AVHD patients were studied. Oxidative stress (OS) was quantified with malon dialdehyde (MD), coupled triens (CT), hepatocuprein (HC) and catalase activity (CA). Liver monooxygenase function (LMF) was evaluated with Т ½ and clearance of antipyrine (Cl АР). Results. On the first postoperative day were characterized by high lipid peroxidation activation (MD, CT, CA: +25, +39, +121,6%; HC: -31.3%) and significant decrease in LMF (Т S АР: +95.4%; Cl АР: -53.1%). On the 3rd-4th and 10th-12th postoperative day were noticed marked OS decrease and LMF increase fitted the baseline. The correlation analysis showed a positive relationship between Т ½ АР and OS parameters, and negative relationship between Cl АР and duration of cardiopulmonary bypass. Conclusion. The cardio-surgical intervention caused significant decrease of MLF (in two times) on the first postoperative day in AVHD patients. Lipid peroxidation activation is one of the main causes of LMF depression. Slowdown of liver microsomal oxidation might change pharmacokinetic response of AVHD patients under drug therapy.