title: Preoperative cerebral hypoperfusion in the left, not in the right, hemisphere is associated with cognitive decline after cardiac surgery.
abstract: OBJECTIVE
  Postoperative cognitive decline (POCD) is a frequent complication after cardiac surgery. Although intraoperative events are risk factors for POCD, the role played by preoperative hypoperfusion in cognitive decline has not yet been investigated. It is also unknown whether the impact of preoperative hypoperfusion in the left or right middle cerebral arteries (MCAs) can differentially account for POCD. The main aims of this study were to investigate whether preoperative cerebral hypoperfusion was associated with early POCD and whether lateralized hypoperfusion would differentially affect POCD in patients after cardiac surgery.
  
  
  METHODS
  Bilateral MCA continuous transcranial Doppler (TCD) sonography was preoperatively performed at rest in 31 right-handed patients who underwent cardiac surgery to detect cerebral blood flow (CBF) velocity. All patients completed a neuropsychological evaluation to assess attention, short-term memory, working memory, and psychomotor function before surgery and at discharge. POCD was defined using the standard deviation method. Logistic regression was used to investigate the association between hypoperfusion and POCD, controlling for common preoperative risk factors.
  
  
  RESULTS
  Fourteen patients (45%) exhibited POCD. Cerebral hypoperfusion in the left MCA selectively predicted the incidence of POCD (odds ratio = 0.90, p < .02), whereas CBF velocity in the right MCA was unrelated to POCD (odds ratio = 1.07, p = .39).
  
  
  CONCLUSIONS
  Patients who underwent cardiac surgery with reduced CBF velocity in the left MCA preoperatively are at greater risk for POCD. Left cerebral hypoperfusion may also represent an independent predictor of POCD in these patients. TCD evaluation may have substantial clinical benefits for the detection of patients at high risk of POCD after cardiac surgery.
authors.affiliation: Department of General Psychology, University of Padua, via Venezia, 35131 Padua, Italy. simone.messerotti@unipd.it
authors.forename: Simone
authors.initials: S
authors.lastname: Messerotti Benvenuti
authors.forename: Paolo
authors.initials: P
authors.lastname: Zanatta
authors.forename: Carolina
authors.initials: C
authors.lastname: Longo
authors.forename: Anna Paola
authors.initials: AP
authors.lastname: Mazzarolo
authors.forename: Daniela
authors.initials: D
authors.lastname: Palomba
mesh_terms: D001783:Blood Flow Velocity; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D054022:Cerebrum / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000503:physiopathology; D003072:Cognition Disorders / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D057234:Preoperative Period; D012307:Risk Factors; D017585:Ultrasonography, Doppler, Transcranial