title: Frequent premature atrial contractions in stroke of undetermined etiology.
abstract: BACKGROUND
  The cause of ischemic stroke is undetermined in 15-40% of patients. We studied the association between frequent premature atrial contractions (PAC) and stroke of undetermined etiology.
  
  
  METHODS
  We retrospectively studied ischemic stroke patients who were consecutively admitted to our department and underwent 24-hour Holter ECG recording including 163 noncardioembolic stroke patients (group A), 24 stroke patients of undetermined etiology (group B), and 37 cardioembolic stroke patients with prior-diagnosed paroxysmal atrial fibrillation (group C). The number of PAC per 24 h and the prevalence of patients with frequent PAC (200 or more per 24 h) were compared between the groups.
  
  
  RESULTS
  The number of PAC was significantly larger in groups B and C than in group A. The proportion of patients with frequent PAC was larger in group B (13/24, 54%) and in group C (18/37, 48%) than in group A (32/163, 20%).
  
  
  CONCLUSIONS
  Our data suggest that frequent PAC should be regarded as a masked type of paroxysmal atrial fibrillation and should be included in one of the causes of cardioembolic stroke.
authors.affiliation: Cerebrovascular Division, Department of Medicine, National Cardiovascular Center, Suita, Japan. ktodo@kcgh.gr.jp
authors.forename: Kenichi
authors.initials: K
authors.lastname: Todo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Moriwaki
authors.forename: Kozue
authors.initials: K
authors.lastname: Saito
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Naritomi
mesh_terms: D000368:Aged; D016275:Atrial Function / Q000502:physiology*; D018880:Atrial Premature Complexes / Q000150:complications* / Q000503:physiopathology; D002545:Brain Ischemia / Q000209:etiology*; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D009200:Myocardial Contraction; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000209:etiology*