Brain SPECT imaging and neuropsychological testing in coronary artery bypass patients: single photon emission computed tomography.
BACKGROUND
Cognitive deficits appear frequently after cardiac operation. While the etiology remains unclear, alterations in cerebral perfusion during cardiopulmonary bypass may be causative. Single photon emission computed tomography (SPECT) scanning utilizes a radiopharmaceutical to provide images of cerebral perfusion. We proposed to study the cerebral circulation of patients during coronary artery bypass operation employing cardiopulmonary bypass.


METHODS
Thirty-five neurologically normal patients underwent preoperative SPECT brain scanning and neuropsychological testing. A second SPECT brain perfusion scan was obtained by administering the radioisotope during cardiopulmonary bypass, with subsequent scanning upon completion of the procedure. Postoperative neuropsychological testing was performed prior to discharge.


RESULTS
Fourteen (40%) of patients demonstrated significant neuropsychological decline. Patients who suffered cognitive impairment were no different in demographic, general health, or surgical variables. Patients who demonstrated neuropsychological decline had significantly poorer cerebral perfusion both at baseline and during operation.


CONCLUSIONS
Impaired cerebral perfusion at baseline may identify patients at risk for cognitive injury after cardiac operation. Alterations in cerebral perfusion during cardiopulmonary bypass is common, and may be a factor in neuropsychological deficits seen after cardiac operation.
Hall
R A
RA
Department of Physical Medicine and Rehabilitation, Virginia Mason Medical Center, Seattle, Washington, USA. r.alanhall@vmmc.org
Fordyce
D J
DJ
Lee
M E
ME
Eisenberg
B
B
Lee
R F
RF
Holmes
J H
JH
Campbell
W G
WG
D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging*; D002315:Cardiopulmonary Bypass; D002560:Cerebrovascular Circulation; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012307:Risk Factors; D015899:Tomography, Emission-Computed, Single-Photon