Clinical significance of aortic spontaneous echo contrast in patients with nonvalvular atrial fibrillation.

Abstract

Little is known about spontaneous echo contrast (SEC) in the descending aorta (DASEC), occurring with or without SEC in the left atrium (LASEC), in the presence of atrial fibrillation (AF). We examined the clinical significance of DASEC, including its relationship with LASEC, in patients with nonvalvular AF. Among 176 patients, 41 (23%) had DASEC and 51 (29%) had LASEC. The patients were divided into four groups based on the presence/absence of LASEC and DASEC, as Group A: no SEC (n=107); Group B: only LASEC (n=28); Group C: only DASEC (n=18); and Group D: both types of SEC (n=23). Clinical and echocardiographic parameters were compared between groups, and the possible determinants of DASEC were evaluated. Age, sex, and CHA2 DS2 -VASc score were similar in the four groups. Group D was more likely to have an increased LA diameter, decreased left ventricular ejection fraction (LVEF), and low LA appendage velocity compared to Group A. Group C had a smaller LA diameter and a higher appendage velocity than Group B. Multivariate logistic regression analysis, with age ≥75 years, female sex, LASEC, LVEF<50%, and presence of DA plaques included as covariates, showed that LASEC (OR 4.22, 95% CI 1.92-9.26, p<.001) and LVEF<50% (OR 2.70, 95% CI 1.12-6.52, p=.027) were significant determinants of DASEC. The prevalence of DASEC increased with increasing LASEC severity in order of none (13%), mild (28%), and dense (50%) (p<.001). In nonvalvular AF patients, DASEC is common, and it partly originates from LASEC, particularly in the presence of LV systolic dysfunction.