RESUMO
Objective and methods There is little information concerning the influence of the heart rhythm on the vascular endothelial function in patients with non-valvular atrial fibrillation (AF) compared with studies concerning sinus rhythm (SR). The present study included paroxysmal (n=184) or chronic (n=53) AF patients without heart failure and control subjects with SR (n=79) matched for age, gender and the CHA2DS2-VASc score. Paroxysmal AF was defined as episodes that terminated spontaneously within 7 days, while chronic AF was defined as longstanding AF that was refractory to cardioversion for 12 months or longer. There were no significant differences in the numbers of patients receiving renin-angiotension-aldosterone system inhibitors or statins among the three groups. Results Among the 237 AF patients (155 men, mean age 64±9 years, mean CHA2DS2-VASc score 1.8±1.4), the flow-mediated dilatation (FMD) was 5.4%±2.6% in the paroxysmal AF group, 4.3%±2.1% in the chronic AF group and 6.5%±3.5% in the SR group. There were significant differences among the 3 groups (all, p<0.05). Nitroglycerin-induced dilatation (NMD) was noted in 14.6%±6.5% of the paroxysmal AF group, 16.5%±9.1% of the chronic AF group and 12.7%±5.9% of the SR group, with no significant differences among the 3 groups. There was a significant negative correlation between the CHA2DS2-VASc scores and the FMDs value in all 3 groups (paroxysmal AF group:r=-0.322, p<0.01; chronic AF group:r=-0.291, p<0.05; SR group:r=-0.326, p<0.01). Conclusion In comparison with SR, the frequency and duration of AF episodes appear to cause deterioration of the vascular endothelial function.