Endothelial dysfunction predicts cardiovascular events in patients with paroxysmal atrial fibrillation

  AIM  To examine the relationship between endothelial dysfunction (measured by flow-mediated dilation, FMD) and cardiovascular events in patients with paroxysmal atrial fibrillation (AF).

  METHODS  In this prospective observational study, FMD of brachial artery was measured by ultrasound in 291 patients with paroxysmal AF and 40 patients with sinus arrhythmia. The AF patients were divided into low FMD group (n=97, FMD<5.9%) or high FMD group (n=194, FMD≥ 5.9%). The patients were followed up for at least 30 months and primary end point was cardiovascular events, including stroke, heart failure hospitalization, cardiovascular death and non-fatal myocardial infarction.

  RESULTS  The average age of low FMD atrial fibrillation group was higher than that of the control group (P<0.05), and it was also higher in high FMD atrial fibrillation group (P<0.05). The CHA₂DS₂ VASc score in low FMD atrial fibrillation group was significantly higher than that in FMD atrial fibrillation group (P<0.05). At the same time, cardiac ultrasound data showed that the value of left atrial end diameter in low FMD atrial fibrillation group was higher than that in control group (P<0.01), and it was also higher in high FMD atrial fibrillation group (P<0.05); The left atrial end diameter in the high FMD group was also significantly higher than that in the control group (P<0.01). Compared with the control group, the incidence of cardiovascular events increased in the low FMD atrial fibrillation group (P<0.01) and in the high FMD atrial fibrillation group (P<0.05); Compared with the low FMD AF group, the high FMD AF group had a lower incidence of cardiovascular events (P<0.05); There were significant differences in the incidence of cardiovascular events, mainly heart failure and stroke. Logistic multivariate regression analysis showed that low FMD value (OR=1.941, 95% CI 1.005～3.748, P<0.05), CHA₂DS₂ VASc score (OR=1.415, 95% CI 1.024～1.956, P<0.05) and LAD value (OR=1.055, 95% CI 1.013～1.099, P≤0.01) were independent risk factors for cardiovascular events in patients with paroxysmal atrial fibrillation.

  CONCLUSION  In patients with paroxysmal AF, endothelial dysfunction is associated with cardiovascular events, especially heart failure. FMD is a significant predictor of cardiovascular events independent of conventional cardiovascular risk in patients with paroxysmal AF.