Association of prolidase activity, oxidative parameters, and presence of atrial fibrillation in patients with mitral stenosis.

Background: Mitral stenosis (MS) is a common cause of atrial fibrillation (AF). Oxidative stress and inflammation factors were shown to be involved in atrial remodeling. The study aim was to compare the oxidative parameters and prolidase activity in severe MS patients with and without AF.

Methods: The study population was comprised of 33 patients with MS and sinus rhythm (group I), 27 patients with MS and AF (group II), and 25 healthy controls (group III). Plasma prolidase activity, total antioxidant capacity (TAC), total oxidative status (TOS), and oxidative stress index (OSI) were determined. Additionally, we measured tissue TOS and TAC in patients with mitral valve replacement.

Results: TAC and OSI were higher, but TOS and prolidase were lower in patients with MS than control (all p <0.001). These parameters were similar in group I and group II (ANOVA p >0.05). Tissue TAC was significantly lower in group II than group I (0.015 +/- 0.01 vs. 0.026 +/- 0.01 mmol Trolox equiv/L, p = 0.014), tissue TOS was similar between groups I and II (0.24 +/- 0.06 vs. 0.22 +/- 0.05 mmol Trolox equiv/L, p = 0.161). Presence of AF was correlated with systolic blood pressure, left atrial diameter, plasma TAC, tissue TAC, plasma TOS, plasma OSI, and plasma prolidase activity. Tissue TAC level (beta = -0.435, p = 0.006) and left atrial diameter (beta = 0.460, p = 0.003) were independently related with presence of AF in patients with MS.

Conclusions: This study suggested that the presence of AF in patients with severe MS may be associated with the plasma prolidase activity, tissue and plasma oxidative parameters.