Off-pump coronary bypass surgery: risk of ischemic brain lesions in patients with atheromatous thoracic aorta.
OBJECTIVE
The purpose of this study was to determine if there is an association between the proximal thoracic aortic (ascending aorta and aortic arch) atheroma and ischemic brain lesions on diffusion-weighted magnetic resonance imaging (DW-MRI) after on-pump (ONCAB) and off-pump (OPCAB) coronary artery bypass surgery.


METHODS
Patients who underwent ONCAB surgery (n = 13) and who had aortic atheroma > 2 mm were compared to a risk-adjusted prospective cohort of patients (n = 13) undergoing OPCAB surgery. Transesophageal echocardiography and epiaortic scanning were performed to assess the proximal thoracic aorta. Patients were evaluated for new ischemic brain lesions utilizing DW-MRI three to seven days after surgery. The NEECHAM confusion scale was used to evaluate patient consciousness.


RESULTS
The groups were comparable with respect to demographic data, and prevalence of preoperative risk factors. The extent and severity of aortic atheroma was similar in the two groups. The average maximum height of atheroma was 5.0 +/- 2.0 mm in the OPCAB and 4.8 +/- 1.9 in the ONCAB groups, respectively. The prevalence of new ischemic brain lesions on DW-MRI was 0% in the OPCAB group and 61% in the ONCAB group (P = 0.001). Patients in the OPCAB group were less confused during the first two postoperative days.


CONCLUSIONS
Patients with aortic atheroma > 2 mm may have a lower risk of new ischemic brain lesions as identified by DWMRI after OPCAB surgery. Patient stratification based upon aortic atheroma burden should be addressed in future trials designed to tailor treatment strategies to improve short- and long-term neurological outcomes in patients undergoing cardiac surgery.
Djaiani
George
G
Department of Anesthesia and Pain Medicine, Eaton North 3-410, Toronto General Hospital, University of Toronto, Ontario M5G 2C4, Canada. george.djaiani@uhn.on.ca
Fedorko
Ludwik
L
Cusimano
Robert J
RJ
Mikulis
David
D
Carroll
Jo
J
Poonawala
Humara
H
Beattie
Scott
S
Karski
Jacek
J
D000368:Aged; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000601:surgery*; D001018:Aortic Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D050197:Atherosclerosis / Q000000981:diagnostic imaging / Q000601:surgery*; D002545:Brain Ischemia / Q000209:etiology*; D015331:Cohort Studies; D003221:Confusion / Q000145:classification; D003243:Consciousness / Q000502:physiology; D001026:Coronary Artery Bypass; D047549:Coronary Artery Bypass, Off-Pump; D038524:Diffusion Magnetic Resonance Imaging; D017548:Echocardiography, Transesophageal; D005260:Female; D006801:Humans; D008297:Male; D011183:Postoperative Complications; D011446:Prospective Studies; D012307:Risk Factors; D016896:Treatment Outcome