Determinants of aortic artifacts during transesophageal echocardiography of the ascending aorta

Background The origin of artifacts of the ascending aorta during transesoph ageal echocardiography has not been widely studied. This study was undertak en to investigate in vivo whether anatomic features could determine the app earance of artifacts. Methods and Results Transesophageal echocardiograms of 46 patients studied for suspected dissection with proven diagnosis (30 patients with and 16 wit hout ascending aortic dissection) were reviewed. The incidence of artifacts was 46%, and it was similar in patients with and those without dissection (chi-square 0.516; P = not significant). Artifacts were located in the aort ic lumen twice as for from the transducer as the atrial-aortic interface. T he aortic diameter was larger in patients with than in those without artifa cts (6.4 +/- 1.1 vs 4.2 +/- 0.9 cm, P < .001). An aortic diameter >5 cm and an atrial-aortic ratio less than or equal to 0.6 predicted the artifact ap pearance with good sensitivity, specificity, positive and negative predicti ve values, and diagnostic accuracy; these parameters reached a value of 100 % by analysis only of patients without dissection. Conclusions An ascending aortic diameter >5.0 cm that exceeds the left atri al diameter with an atrial-aortic ratio less than or equal to 0.6 creates i n vivo the conditions for the reverberation of the atrial-aortic interface within the aorta. Therefore, in patients with such anatomic Features, artif acts must be suspected in the presence of linear structures within the aort a.