Effect of fish oil on circulating asymmetric dimethylarginine and adiponectin in overweight or obese patients with atrial fibrillation.

Obesity and adipose-derived peptides might be involved in the pathogenesis of atrial fibrillation (AF). Adiponectin plays a major role in the modulation of several metabolic pathways, and asymmetric dimethylarginine (ADMA) has been suggested to be predictive of AF and associated adverse events. The aim of this study was to investigate the effect of fish oil supplementation on circulating adiponectin and ADMA in overweight or obese patients with persistent AF. In this randomized, double-blind, placebo-controlled trial, 80 overweight or obese (body mass index (BMI) ≥ 25 kg/m2) patients with persistent AF were randomly assigned to two groups to receive either 2 g/day fish oil or placebo, for 8 weeks. Serum levels of adiponectin and ADMA, and anthropometric indexes were measured. This study showed that serum adiponectin concentrations increased significantly following fish oil supplementation compared with the placebo group (13.15 ± 7.33 vs. 11.88 ± 6.94 µg/ml; p = .026). A significant reduction was also observed in serum ADMA levels in the fish oil compared with the placebo group following the intervention (0.6 ± 0.13 vs. 0.72 ± 0.15 µmol/L; p = .001). The changes in serum adiponectin and ADMA concentrations remained significant after adjustments for baseline values, age, sex, and changes of BMI and waist circumference (p = .011 and p = .001, respectively). In conclusion,  8 weeks supplementation with fish oil increased serum adiponectin and decreased ADMA concentrations in overweight or obese patients with persistent AF. As adiponectin and ADMA are suggested to be involved in many pathways associated with AF, the current findings might be promising in the clinical management of this disease, an issue that needs further investigations.

Fish oil supplementation for primary prevention of atrial fibrillation after coronary artery bypass graft surgery: A randomized clinical trial.

BACKGROUND: Atrial fibrillation (AF) after cardiac surgery is a common complication that may influence patients' early and long term outcomes and hospital costs. The purpose of this study was to assess the effect of fish oil on occurrence of AF following coronary artery bypass graft surgery (CABG). METHODS: This study was a single-center, randomized, double blinded, placebo-controlled clinical trial. Four-hundred and one patients undergoing coronary artery bypass graft surgery were randomly assigned to receive 2 g/d fish oil or placebo (olive oil) for at least 5 days before surgery. The primary end point was defined as time to AF improvement After AF incidence following isolated CABG or a need for pharmacologic therapy or cardioversion. RESULTS: The time to AF improvement in intervention group was shorter than control group (HR: 2.05; 95% CI = 0.70-6.22, P = 0.20). The incidence of AF in the intervention and control groups was 8.40% vs. 14.07% respectively (p = 0.07). Mean total duration of AF was 20.96 ± 4.71 h in intervention groups and 46.87 ± 7.44 h in control groups (p = 0.04). Mean duration of stay in the ICU and total hospital stay showed a significant reduction in the intervention group (p = 0.003 and p = 0.04, respectively). CONCLUSION: The consumption of PUFA leads to a shorter time to AF improvement, which was not statistically significant. The incidence of AF in patients undergoing CABG surgery was decreased by approximately 5.7%; which was statistically on the borderline. Fish oil reduced median length of stay in the ICU and hospital. Further well-designed studies are needed to overcome the limitations of the existing trials and provide conclusive conclusions.

Assessment of Apelin Serum Levels in Persistent Atrial Fibrillation and Coronary Artery Disease.

BACKGROUND: Apelin, the endogenous ligand of orphan receptor APJ (gene symbol APLNR), is an adipokine that was suggested to have a direct correlation with obesity. This peptide might play a role in obesity-related disorders, especially in the cardiovascular system. Currently, few data are available on levels and potential metabolic functions of apelin in different cardiac diseases including atrial fibrillation (AF) and coronary artery disease (CAD), which have common underlying pathophysiological mechanisms. This study aimed to investigate apelin levels in patients with AF and CAD that were overweight or obese, as well as its relationship with anthropometry and metabolic profile. METHODS: This preliminary investigation was compromised of 41 patients with AF and 39 with CAD aged > 50 years and body mass index (BMI) > 25kg/m2. Serum levels of apelin, fasting plasma glucose, insulin, homeostatic model assessment, triglyceride, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and very-low-density lipoprotein were measured. RESULTS: The apelin serum levels were not statistically different between patients with AF and CAD. A negative correlation was observed between apelin with weight (r = -0.257, P = 0.023) and BMI (r = -0.258, P = 0.023). Moreover, apelin showed an inverse correlation with insulin (r =-0.227, P = 0.045) and marginally with homeostatic model assessment (r = -0.21, P = 0.066). There was a negative association between apelin and triglyceride (r = -0.238, P = 0.036) and very-low-density lipoprotein (r = -0.25, P = 0.027). CONCLUSIONS: Apelin serum levels were not significantly different among patients with AF and CAD. The unexpected inverse correlation of apelin with weight and BMI might indicate the dominant effects of pathophysiological conditions such as AF and CAD on serum levels of apelin compared with BMI and adipose tissue. Understanding the precise role of apelin in modulating obesity-induced disorders including AF and CAD requires further studies.