title: Incidence and mechanisms of cerebral ischemia after transcatheter aortic valve implantation compared with surgical aortic valve replacement.
abstract: BACKGROUND
  The most likely mechanisms of neurologic injury after transcatheter aortic valve implantation (TAVI) and aortic valve replacement (AVR) are cerebral embolization and hypoperfusion. We set out to determine potential mechanisms of neurologic injury after TAVI compared with AVR.
  
  
  METHODS
  One hundred twenty-seven consecutive high-risk patients with severe aortic stenosis (AS) who underwent TAVI (n = 85) or AVR (n = 42) were studied. Transcranial Doppler ultrasound (TCD), cerebral oximetry, diffusion-weighted magnetic resonance imaging (DW-MRI) (before, 6 days, and 3 months after procedure), and neurocognitive assessment before and at 3 months were performed.
  
  
  RESULTS
  Neurologic injury was not significantly different between TAVI and AVR at 1 (1.1% vs 2.2%, p = 0.25) and 3 months (4.7% vs 2.2%, p = 1). At 3 months, overall cognitive score was higher in AVR compared with TAVI when adjusted for baseline score; the estimated difference between groups was 0.63 (95% confidence interval 0.87% to 1.17%; p = 0.02). Cerebral embolic load was 212 (123 to 344) during AVR and 134 (76 to 244) during TAVI (p = 0.07). Cerebral oxygen desaturation during AVR (7.56 ± 2.16) was higher compared with TAVI (5.93 ± 2.47) (p < 0.01). Ischemic lesions measured by DW-MRI occurred in 76% of TAVI and 71% of AVR patients at 6 days (p = 0.69) and 63% and 39% at 3 months (p = 0.11). No significant association was found between cerebral emboli, cerebral oxygen desaturation, brain ischemic lesions, and general cognitive score.
  
  
  CONCLUSIONS
  At 3 months follow-up, overall cognitive score was higher in AVR compared with TAVI, adjusted for baseline score. However, there was no difference in cerebral embolic load, ischemic lesions, and oxygen desaturation.
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: Aiman
authors.initials: A
authors.lastname: Alassar
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: Gopal
authors.initials: G
authors.lastname: Soppa
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: Edsell
authors.affiliation: Department of Neuroradiology, St. George's Hospital, London, United Kingdom.
authors.forename: Philip
authors.initials: P
authors.lastname: Rich
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Roy
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: Irina
authors.initials: I
authors.lastname: Chis Ster
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: Ruth
authors.initials: R
authors.lastname: Joyce
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom.
authors.forename: Oswaldo
authors.initials: O
authors.lastname: Valencia
authors.affiliation: Department of Neuroradiology, St. George's Hospital, London, United Kingdom.
authors.forename: Thomas
authors.initials: T
authors.lastname: Barrick
authors.affiliation: Department of Neuroradiology, St. George's Hospital, London, United Kingdom.
authors.forename: Franklyn
authors.initials: F
authors.lastname: Howe
authors.affiliation: Department of Cardiac Surgery, Royal Brompton Hospital, London, United Kingdom.
authors.forename: Neil
authors.initials: N
authors.lastname: Moat
authors.affiliation: Department of Psychology, King's College Hospital, London, United Kingdom.
authors.forename: Robin
authors.initials: R
authors.lastname: Morris
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Hugh S
authors.initials: HS
authors.lastname: Markus
authors.affiliation: Department of Cardiac Surgery, Cardiology and Anesthesia, St. George's Hospital, London, United Kingdom. Electronic address: marjan.jahangiri@stgeorges.nhs.uk.
authors.forename: Marjan
authors.initials: M
authors.lastname: Jahangiri
mesh_terms: D001024:Aortic Valve Stenosis / Q000601:surgery*; D002545:Brain Ischemia / Q000453:epidemiology* / Q000209:etiology*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000379:methods*; D006801:Humans; D015994:Incidence; D020766:Intracranial Embolism / Q000209:etiology / Q000601:surgery; D065467:Transcatheter Aortic Valve Replacement / Q000009:adverse effects