Prevention of Postoperative Atrial Fibrillation: Novel and Safe Strategy Based on the Modulation of the Antioxidant System

Abstract

Postoperative atrial fibrillation (AF) is the most common arrhythmia following cardiac surgery with extracorporeal circulation. The pathogenesis of postoperative AF is multifactorial. Oxidative stress, caused by the unavoidable ischemia–reperfusion event occurring in this setting, is a major contributory factor. Reactive oxygen species (ROS)-derived effects could result in lipid peroxidation, protein carbonylation, or DNA oxidation of cardiac tissue, thus leading to functional and structural myocardial remodeling. The vulnerability of myocardial tissue to the oxidative challenge is also dependent on the activity of the antioxidant system. High ROS levels, overwhelming this system, should result in deleterious cellular effects, such as the induction of necrosis, apoptosis, or autophagy. Nevertheless, tissue exposure to low to moderate ROS levels could trigger a survival response with a trend to reinforce the antioxidant defense system. Administration of n−3 polyunsaturated fatty acids (PUFA), known to involve a moderate ROS production, is consistent with a diminished vulnerability to the development of postoperative AF. Accordingly, supplementation of n−3 PUFA successfully reduced the incidence of postoperative AF after coronary bypass grafting. This response is due to an up-regulation of antioxidant enzymes, as shown in experimental models. In turn, non-enzymatic antioxidant reinforcement through vitamin C administration prior to cardiac surgery has also reduced the postoperative AF incidence. Therefore, it should be expected that a mixed therapy result in an improvement of the cardioprotective effect by modulating both components of the antioxidant system. We present novel available evidence supporting the hypothesis of an effective prevention of postoperative AF including a two-step therapeutic strategy: n−3 PUFA followed by vitamin C supplementation to patients scheduled for cardiac surgery with extracorporeal circulation. The present study should encourage the design of clinical trials aimed to test the efficacy of this strategy to offer new therapeutic opportunities to patients challenged by ischemia–reperfusion events not solely in heart, but also in other organs such as kidney or liver in transplantation surgeries.

Postoperative Atrial Fibrillation in Liver Transplantation

“…Management of POAF has been extensively studied in cardiac and thoracic patients and the guidelines on the management of these patients have been regularly updated (1,(22)(23)(24)(25)(26). Several large prospective, randomized trials and meta-analyses in cardiac surgery show pharmacologic agents can effectively reduce POAF (1).…”

Impact of antioxidant supplementations on cardio‐renal protection in cardiac surgery: an updated and comprehensive meta‐analysis and systematic review

“…Reactive oxygen species (ROS) are involved in the structural and electrical remodeling of the myocardium. In particular, NADPH oxidase can be activated by well‐known triggers of AF, such as angiotensin II and atrial stretch . Cellular damage is mediated by an alteration in the antioxidant status, which increases the concentration of ROS in oxidative stress.…”

“…In particular, NADPH oxidase can be activated by well-known triggers of AF, such as angiotensin II and atrial stretch. 5,6 Cellular damage is mediated by an alteration in the antioxidant status, which increases the concentration of ROS in oxidative stress. Oxidative stress mediates a wide spectrum of renal impairments, from acute renal failure, obstructive nephropathy to chronic renal failure, and hemodialysis.…”

Effect of dietary supplementation of tiger nut (Cyperus esculentus l.) and walnut (Tetracarpidium conophorum müll. Arg.) on sexual behavior, hormonal level, and antioxidant status in male rats

“…Oxidative stress interferes with the NO pathway and causes vascular damage (Jeremy et al, 2000;Jones et al, 2002). Antioxidant enzymes such as SOD, CAT, and glutathione peroxidase are the first line of defense against oxidative injury (Rodrigo, 2012). SOD protects tissues against oxygen free radicals by catalyzing the removal of superoxide radicals, converting them to H 2 O 2 and molecular oxygen, which damages the cell membrane and other biological structures (Arivazhagan, Thilagavathy, & Pannerselvam, 2000).…”