Atrial nitroso-redox balance and refractoriness following on-pump cardiac surgery: a randomized trial of atorvastatin.

Aims: Systemic inflammation and increased activity of atrial NOX2-containing NADPH oxidases have been associated with the new onset of atrial fibrillation (AF) after cardiac surgery. In addition to lowering LDL-cholesterol, statins exert rapid anti-inflammatory and antioxidant effects, the clinical significance of which remains controversial.

Methods And Results: We first assessed the impact of cardiac surgery and cardiopulmonary bypass (CPB) on atrial nitroso-redox balance by measuring NO synthase (NOS) and GTP cyclohydrolase-1 (GCH-1) activity, biopterin content, and superoxide production in paired samples of the right atrial appendage obtained before (PRE) and after CPB and reperfusion (POST) in 116 patients.

Myocardial redox state predicts in-hospital clinical outcome after cardiac surgery effects of short-term pre-operative statin treatment.

Objectives: The purpose of this study was to evaluate the role of the myocardial redox state in the development of in-hospital complications after cardiac surgery and the effect of statins on the myocardial redox state.

Background: Statins improve clinical outcome after cardiac surgery, but it is unclear whether they exert their effects by modifying the myocardial redox state.

Methods: We quantified myocardial superoxide anion (O(2)(-)) and peroxynitrite (ONOO(-)) and their enzymatic sources in samples of the right atrial appendage (RAA) from 303 patients undergoing cardiac surgery who were followed up until discharge, and in 42 patients who were randomized to receive 3-day treatment with atorvastatin 40 mg/d or placebo before surgery.

Atrial sources of reactive oxygen species vary with the duration and substrate of atrial fibrillation: implications for the antiarrhythmic effect of statins.

Background: An altered nitric oxide-redox balance has been implicated in the pathogenesis of atrial fibrillation (AF). Statins inhibit NOX2-NADPH oxidases and prevent postoperative AF but are less effective in AF secondary prevention; the mechanisms underlying these findings are poorly understood.

Methods And Results: By using goat models of pacing-induced AF or of atrial structural remodeling secondary to atrioventricular block and right atrial samples from 130 patients undergoing cardiac surgery, we found that the mechanisms responsible for the NO-redox imbalance differ between atria and with the duration and substrate of AF.