Pathologic correlates of aortic plaques, thrombi and mobile "aortic debris" imaged in vivo with transesophageal echocardiography.

OBJECTIVES

This study sought to evaluate the pathologic correlates of aortic atheromas, thrombi and mobile "aortic debris" imaged in vivo by transesophageal echocardiography (TEE).

BACKGROUND

Atherosclerotic plaques with various complexity, thrombi and debris are frequently identified by TEE during imaging of the aorta. However, pathologic data to characterize these lesions imaged in vivo are lacking.

METHODS

Intraoperative TEE was performed prospectively in 31 patients undergoing repair of aortic aneurysm or dissection. TEE was used to guide the surgeon to mark aortic areas of interest that were sent for pathologic examination. A four-point scoring system was used for both TEE and pathologic evaluation to grade the degree of involvement of the aortic wall with atheroma. Ultrasound video intensity of the aortic wall lesions was measured and compared with quantitative measures of wall composition at pathologic examination. The presence of thrombi and mobile aortic debris by TEE was noted and compared with pathologic findings.

RESULTS

Histologic-TEE correlations were possible in 62 aortic segments. There was 73% exact agreement between TEE and pathologic grading. Discrepancies were mostly in the inability of TEE to detect superficial ulcerations. However, separation of normal aorta and minimal intimal thickening (grades I and II) from more complex atheromas (grades III and IV) was observed in 93%. For identification of thrombus, TEE had a sensitivity of 91% (29 of 32 segments) and a specificity of 90% (27 of 30 segments). Mobile aortic debris were identified in six aortic segments and were confirmed at pathologic examination to be thrombi. Ultrasound video intensity increased with worsening complexity of atheroma and related significantly to aortic plaque composition at pathologic evaluation (r = 0.80, p < 0.0001). Ultrasound intensity of thrombi and mobile debris was similar and was lower than that of complex atheromas.

CONCLUSIONS

Thus, in the evaluation of aortic pathologic segments, TEE can assess aortic plaque complexity and identify thrombus formation, findings that may have important therapeutic implications.