Endothelial dysfunction predicted cardiovascular events in patients with paroxysmal atrial fibrillation

OBJECTIVES: To examine the relationship between endothelial dysfunction and adverse cardiovascular events in patients with paroxysmal atrial fibrillation (AF). METHODS: In this prospective observational study, flow-mediated dilation (FMD) was measured by ultrasound in 291 patients with paroxysmal AF. Then, the patients were divided into low FMD group (n=97, FMD of <5.9%) or high FMD group (n=194, FMD of ≥5.9%). Patients were followed up for at least 30 months. Primary end point was cardiovascular events (stroke, heart failure hospitalization, cardiovascular death, and non-fatal myocardial infarction) and second endpoint was heart failure hospitalization, or stroke. RESULTS: Rate of cardiovascular events was higher in low FMD group compared with high FMD group (37.1% versus 18%, p<0.001). This higher risk of cardiovascular events in patients with low FMD was primarily due to a higher risk of heart failure hospitalization compared with patients with high FMD (19.6% versus 10.8%, p<0.05). There was no significant difference of stroke between both groups. Cox proportional hazards ratio (HR) analysis showed that low FMD (HR: 3.036, 95% CI: [1.546-5.963], CHA2DS2-VASc scores (HR: 1.383, 95% CI: [1.035-1.847]), and left atrial diameter (HR: 1.304, 95% CI: [1.001-1.069]) were independent predictors for composite cardiovascular events. CONCLUSION: In patients with paroxysmal AF, endothelial dysfunction was associated with composite cardiovascular events. Flow-mediated dilation was a significant predictor of cardiovascular events in patients with paroxysmal AF.