Ultrasonographic demonstration of manipulation-related aortic injuries after cardiac surgery.

OBJECTIVES This study was performed to evaluate the frequency and risk factors associated with new aortal lesions induced by surgical manipulation and their correlation with postoperative stroke. BACKGROUND Little is known about the causative mechanism of intraoperative atheroembolism after cardiac surgery. METHODS Epiaortic echocardiography was performed before cannulation and after decannulation in 472 patients undergoing cardiac surgery with extracorporeal circulation. RESULTS A new lesion in the ascending aortal intima was identified in 16 patients (3.4%) after decannulation. New lesions were severe, with mobile lesions or disruption of the intima in 10 patients. Six of the severe lesions were related to aortic damping and the other four to aortic cannulation. Three patients in this group had postoperative stroke. Univariate analysis identified only the maximal thickness of the atheroma near the aorta manipulation site as a predictor of new lesions. The incidence of new lesions was 11.8% if the atheroma was approximately 3 to 4 mm thick and as high as 33.3% if the atheroma was >4 mm, but only 0.8% when it was <3 mm. Total 10 patients (2.1%) sustained neurological complications. Arteriosclerosis obliterans, atherosclerosis of the aorta and new mobile lesions were identified as predictors of strokes. CONCLUSIONS This study demonstrated an association between new lesions created by surgical maneuvers and postoperative stroke. Embolic strokes were more likely to occur if new lesions were complicated with intimal disruption, especially of the mobile type. Modifications in surgical procedures will be needed if thick plaque (especially >4 mm) is noted near the manipulation site.