title: Long-term neurocognitive function after mechanical aortic valve replacement.
abstract: BACKGROUND
  Mechanical aortic valves are a possible source of microemboli potentially causing cerebral injury. Therefore, the long-term impact of mechanical aortic valve replacement on neurocognitive function is uncertain.
  
  
  METHODS
  In this prospective, contemporary study, we followed 32 consecutive patients (aged 51 +/- 8 years; range, 38 to 70; EuroSCORE [European System for Cardiac Operative Risk Evaluation] 4.4 +/- 1.7) undergoing isolated aortic valve replacement with a mechanical prosthesis. A cohort of age- and sex-matched patients (n = 28, aged 50 +/- 7 years) served as nonsurgical controls. After aortic valve replacement, neurocognitive function was serially reevaluated at 7-day (n = 32), 4-month (n = 31), and 3-year (n = 29) follow-up. Neurocognitive function was measured by means of P300 auditory evoked potentials.
  
  
  RESULTS
  Before the operation, P300 peak latencies were comparable between surgical patients (361 +/- 32 ms) and nonsurgical controls (365 +/- 33 ms, p = 0.783). In patients undergoing aortic valve replacement, P300 peak latencies were prolonged 7 days after surgery (380 +/- 32 ms) as compared with before the operation (361 +/- 32 ms, p < 0.0001) and as compared with nonsurgical controls (364 +/- 34 ms, p = 0.002). At 4-month (369 +/- 30 ms, p = 0.752) and 3-year (370 +/- 31 ms, p = 0.825) follow-up, P300 peak latencies normalized as compared with before operation and as compared with nonsurgical controls (4-month follow-up 363 +/- 31 ms, p = 0.832; 3-year follow-up 366 +/- 32 ms, p = 0.432). We found no difference in patients with different valve types.
  
  
  CONCLUSIONS
  Despite previous assumptions based on the potential occurrence of microemboli in patients with mechanical valves, mechanical aortic valve replacement has no adverse long-term impact on neurocognitive function. This finding is only valid for patients with a comparable age range undergoing isolated aortic valve replacement.
authors.affiliation: Department of Cardiothoracic Surgery, University of Vienna, Vienna, Austria. daniel.zimpfer@meduniwien.ac.at
authors.forename: Daniel
authors.initials: D
authors.lastname: Zimpfer
authors.forename: Martin
authors.initials: M
authors.lastname: Czerny
authors.forename: Philipp
authors.initials: P
authors.lastname: Schuch
authors.forename: Richard
authors.initials: R
authors.lastname: Fakin
authors.forename: Christian
authors.initials: C
authors.lastname: Madl
authors.forename: Ernst
authors.initials: E
authors.lastname: Wolner
authors.forename: Michael
authors.initials: M
authors.lastname: Grimm
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D001021:Aortic Valve / Q000601:surgery*; D001281:Atrial Fibrillation / Q000150:complications / Q000453:epidemiology; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D015331:Cohort Studies; D018913:Event-Related Potentials, P300; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D020766:Intracranial Embolism / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D011446:Prospective Studies; D011930:Reaction Time; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants