The impact of aortic manipulation on neurologic outcomes after coronary artery bypass surgery: a risk-adjusted study.
BACKGROUND
Cerebral embolization of atherosclerotic plaque debris caused by aortic manipulation during conventional coronary artery bypass grafting (CABG) is a major mechanism of postoperative cerebrovascular accidents (CVA). Off-pump CABG (OPCABG) reduces stroke rates by minimizing aortic manipulation. Consequently, the effect of different levels of aortic manipulation on neurologic outcomes after CABG surgery was examined.


METHODS
From January 1998 to June 2002, 7,272 patients underwent isolated CABG surgery through three levels of aortic manipulation: full plus tangential (side-biting) aortic clamp application (on-pump surgery; n = 4,269), only tangential aortic clamp application (OPCABG surgery; n = 2,527) or an "aortic no-touch" technique (OPCABG surgery; n = 476). A risk-adjusted logistic regression analysis was performed to establish the likelihood of postoperative stroke with each technique. Preoperative risk factors for stroke from the literature, and those found significant in a univariable model were used.


RESULTS
A significant association for postoperative stroke correspondingly increasing with the extent of aortic manipulation was demonstrated by the univariable analysis (CVA incidence respectively increasing from 0.8% to 1.6% to a maximum of 2.2%, p < 0.01). In the logistic regression model, patients who had a full and a tangential aortic clamp applied were 1.8 times more likely to have a stroke versus those without any aortic manipulation (95% confidence interval: 1.15 to 2.74, p < 0.01) and 1.7 times more likely to develop a postoperative stroke than those with only a tangential aortic clamp applied (95% confidence interval: 1.11 to 2.48, p < 0.01).


CONCLUSIONS
Aortic manipulation during CABG is a contributing mechanism for postoperative stroke. The incidence of postoperative stroke increases with increased levels of aortic manipulation.
Kapetanakis
Emmanouil I
EI
Department of Surgery, Section of Cardiac Surgery, Washington Hospital Center, Washington, DC 20010-2975, USA.
Stamou
Sotiris C
SC
Dullum
Mercedes K C
MK
Hill
Peter C
PC
Haile
Elizabeth
E
Boyce
Steven W
SW
Bafi
Ammar S
AS
Petro
Kathleen R
KR
Corso
Paul J
PJ
D000368:Aged; D001011:Aorta; D001018:Aortic Diseases / Q000150:complications* / Q000175:diagnosis; D001161:Arteriosclerosis / Q000150:complications* / Q000175:diagnosis; D003072:Cognition Disorders / Q000453:epidemiology / Q000209:etiology*; D015897:Comorbidity; D003250:Constriction; D001026:Coronary Artery Bypass / Q000379:methods*; D047549:Coronary Artery Bypass, Off-Pump / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D020766:Intracranial Embolism / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D007431:Intraoperative Complications / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D010173:Palpation; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D012189:Retrospective Studies; D013314:Stress, Mechanical; D016896:Treatment Outcome