Abstract 16891: Beat-to-beat Systolic as Well as Diastolic Blood Pressure Variability is High in Atrial Fibrillation

Abstract

Background: Atrial fibrillation (AF) is associated with an increased risk for cardiovascular morbidity and mortality, beyond thromboembolism. The underlying mechanisms for this association are not fully understood but may involve effects on artery walls and endothelial function. High blood pressure (BP) incurs an increased risk of cardiovascular events. The interplay between AF and BP is insufficiently studied. Material and methods: We studied 33 patients, 21 in AF and 13 in sinus rhythm (SR), during coronary angiography. After catheterization of the radial artery invasive BP was recorded four times at three locations (radial artery, brachial artery (twice) and ascending aorta). BP was recorded for a minimum of 15 consecutive beats. BP variability defined as mean beat-to-beat BP difference was calculated for systolic and diastolic BP at each site. Results: There was a significant difference (p<0.001) in mean systolic and diastolic beat-to-beat BP variability between the AF and SR groups at all locations, see figures. No significant difference in BP variability was seen between locations. RA = Radial Artery; BA = Brachial Artery; AA = Ascending Aorta Conclusions: Beat-to-beat BP variability in patients with AF is substantially higher than in patients with SR. Systolic BP variability was almost twice as high and diastolic BP variability was almost seven times as high in AF as compared to SR. Hemodynamic effects of this beat-to-beat variation in BP may have negative effects on vascular structure and function, possibly contributing to the disproportionate increase in cardiovascular morbidity and mortality seen in AF patients.