HEMODYNAMIC CORRELATES OF SPONTANEOUS ECHO CONTRAST IN THE DESCENDINGAORTA

To identify the hemodynamic associations of spontaneous echo contrast (SEC) in the descending aorta (DA), we measured aortic flow parameters in 102 consecutive patients studied with transesophageal echocardiogr aphy. SEC in the DA was identified in 19 of 102 patients (19%). Patien ts with SEC in the DA were older (67 +/- 9 vs 57 +/- 17 years; p = 0.0 01), had a higher proportion of chronic atrial arrhythmia (13 of 19 vs 11 of 83; p = 0.000001), and had a higher frequency of decreased left ventricular performance (10 of 19 vs 19 of 83; p = 0.01). Patients wi th SEC in the DA had larger aortic diameters (2.9 +/- 0.5 vs 2.3 +/- 0 .4 cm; p 0.0001), lower maximal velocity in the DA (42.6 +/- 12.8 vs 7 5.6 +/- 34.4 cm/s; p = 0.0001), and lower maximal shear rate (61.6 +/- 20.3 vs 139.9 +/- 78.8 s(-1); p = 0.0001). There was no difference in volumetric flow in the DA between groups. In multivariate analysis, o nly arrhythmia (p = 0.008) and maximal shear rate (p = 0.002) were ide ntified as significant independent predictors of SEC in the DA. We con clude that SEC in the DA is related to chronic atrial arrhythmia and s hear rate but not to volumetric flow.