OBJECTIVES This study was performed to evaluate the frequency and risk fact
ors 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 aft
er decannulation in 472 patients undergoing cardiac surgery with extracorpo
real circulation.
RESULTS A new lesion in the ascending aortal intima was identified in 16 pa
tients (3.4%) after decannulation. New lesions were severe, with mobile les
ions or disruption of the intima in 10 patients. Six of the severe lesions
were related to aortic clamping and the other four to aortic cannulation. T
hree patients in this group had postoperative stroke. Univariate analysis i
dentified only the maximal thickness of the atheroma near the aorta manipul
ation site as a predictor of new lesions. The incidence of new lesions was
11.8% if the atheroma was similar to 3 to 4 mm thick and as high as 33.3% i
f the atheroma was >4 mm, but only 0.8% when it was <3 mm. Total 10 patient
s (2.1%) sustained neurological complications. Arteriosclerosis obliterans,
atherosclerosis of the aorta and new mobile lesions were identified as pre
dictors of strokes.
CONCLUSIONS This study demonstrated an association between new lesions crea
ted by surgical maneuvers and postoperative stroke. Embolic strokes were mo
re likely to occur if new lesions were complicated with intimal disruption,
especially of the mobile type. Modifications in surgical procedures will b
e needed if thick plaque (especially >4 mm) is noted near the manipulation
site. (J Am Coil Cardiol 2000;35:1303-10) (C) 2000 by the American College
of Cardiology.