title: Postablation asymptomatic cerebral lesions: long-term follow-up using magnetic resonance imaging.
abstract: BACKGROUND
  Catheter ablation of atrial fibrillation (AF) is complicated by cerebral emboli resulting in acute ischemia. Recently, cerebral ischemic microlesions have been identified with diffusion-weighted magnet resonance imaging (MRI).
  
  
  OBJECTIVE
  The clinical course and longer-term characteristics of these lesions are not known and were investigated in this study.
  
  
  METHODS
  Of 86 patients, 33 (38%) had new asymptomatic cerebral lesions documented on MRI after catheter ablation for AF; 14 of these 33 (42%) underwent repeat MRI at different time intervals (2 weeks to 1 year) during follow-up, and clinical symptoms as well as size and number of residual lesions were documented.
  
  
  RESULTS
  In postablation cerebral MRI, 50 new lesions were identified (3.6 lesions/patient) in 14 patients. No patient presented any neurological symptoms. Distribution of the lesions was predominantly in the left hemisphere (60%) and the cerebellum (26%); 52% of the lesions were small (≤3 mm maximum diameter), 42% were medium (4 to 10 mm) and 3 lesions (6%) had a maximum diameter >10 mm. Follow-up MRI after a median of 3 months revealed 3 residual lesions in 3 of 14 patients corresponding to the large acute postablation lesions (>10 mm). The remaining 47 of 50 (94%) of the small or medium-sized lesions were not detectable at follow-up evaluation.
  
  
  CONCLUSIONS
  Most asymptomatic cerebral lesions observed acutely after AF ablation procedures were ≤10 mm in diameter. 94% of all lesions healed without scarring at follow-up >2 weeks after ablation. The larger acute lesions produced chronic glial scars. Neither chronic nor acute lesions were associated with neurological symptoms.
authors: Department of Electrophysiology, Academic Heart Center Cologne-Porz, Cologne, Germany. thomas.deneke@rub.de
authors: Thomas
authors: T
authors: Deneke
authors: Dong-In
authors: DI
authors: Shin
authors: Osman
authors: O
authors: Balta
authors: Kathrin
authors: K
authors: Bünz
authors: Frank
authors: F
authors: Fassbender
authors: Andreas
authors: A
authors: Mügge
authors: Helge
authors: H
authors: Anders
authors: Marc
authors: M
authors: Horlitz
authors: Markus
authors: M
authors: Päsler
authors: Sinthu
authors: S
authors: Karthikapallil
authors: Thomas
authors: T
authors: Arentz
authors: Dieter
authors: D
authors: Beyer
authors: Martin
authors: M
authors: Bansmann
mesh_terms: D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects*; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis* / Q000209:etiology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013997:Time Factors