title: Predictors of silent brain infarction on magnetic resonance imaging in patients with nonvalvular atrial fibrillation: A transesophageal echocardiographic study.
abstract: BACKGROUND
  Silent brain infarction (SBI) is often found in patients with atrial fibrillation (AF) and may be related to cognitive decline. We investigated the predictors of SBI on brain magnetic resonance imaging (MRI) using transesophageal echocardiography (TEE) in patients with nonvalvular AF.
  
  
  METHODS
  The study population consisted of 103 neurologically asymptomatic patients with nonvalvular AF who underwent TEE before transcatheter AF ablation (76 men; mean age 63 ± 10 years). Left atrial (LA) abnormalities such as LA thrombus, spontaneous echo contrast, or abnormal LA appendage emptying velocity (<20 cm/s) and complex plaques in the aortic arch defined as large plaques ≥4 mm thickness, ulcerated plaques, or mobile plaques were evaluated by TEE. All patients were screened for SBI by brain MRI.
  
  
  RESULTS
  Of 103 patients, 31 (30%) showed SBI on brain MRI. Most lesions were multiple (61%) and small (<15 mm) in diameter (84%). Patients with SBI had a higher prevalence of LA abnormalities (45% vs 14%; P < .001) and complex arch plaques (45% vs 7%; P < .001) compared with those without SBI. In a multivariate logistic regression analysis including age and CHADS2 score ≥2, LA abnormalities (odds ratio 4.13; 95% CI 1.34-12.72; P = .014) and complex arch plaques (odds ratio 4.82; 95% CI 1.23-18.92; P = .024) were independent predictors of SBI.
  
  
  CONCLUSIONS
  Left atrial abnormalities and complex arch plaques detected by TEE were closely associated with the presence of SBI on brain MRI, suggesting that microembolization of small thrombi derived from the fibrillating LA or advanced aortic atherosclerotic lesions may be important causes of SBI in patients with nonvalvular AF.
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan. Electronic address: k-sugioka@med.osaka-cu.ac.jp.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sugioka
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Takagi
authors.affiliation: Department of Radiology, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sakamoto
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Suwako
authors.initials: S
authors.lastname: Fujita
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Asahiro
authors.initials: A
authors.lastname: Ito
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Iwata
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Matsumura
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Nakagawa
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Doi
authors.affiliation: Department of Radiology, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Miki
authors.affiliation: Department of Cardiovascular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Yoshiyama
authors.affiliation: Department of Pathology, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Ueda
mesh_terms: D000368:Aged; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging*; D001281:Atrial Fibrillation / Q000150:complications / Q000000981:diagnostic imaging*; D020520:Brain Infarction / Q000473:pathology*; D017548:Echocardiography, Transesophageal; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging*; D011446:Prospective Studies