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Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
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Frequent premature atrial contractions in stroke of undetermined etiology

Kenichi Todo1, Hiroshi Moriwaki, Kozue Saito

  • 1Cerebrovascular Division, Department of Medicine, National Cardiovascular Center, Suita, Japan. ktodo@kcgh.gr.jp

European Neurology
|March 20, 2009
PubMed

Insights

Frequent premature atrial contractions (PAC) are linked to strokes of unknown causes. This suggests PAC may be a hidden sign of atrial fibrillation, a cause of cardioembolic stroke.

Area of Science:

  • Cardiology
  • Neurology
  • Medical Diagnostics

Background:

  • Ischemic stroke etiology remains undetermined in 15-40% of cases.
  • The association between frequent premature atrial contractions (PAC) and stroke of undetermined origin was investigated.
  • Understanding stroke causes is crucial for effective prevention and treatment.

Purpose of the Study:

  • To determine if frequent premature atrial contractions (PAC) are associated with cryptogenic stroke.
  • To evaluate PAC as a potential indicator for paroxysmal atrial fibrillation in stroke patients.
  • To explore the role of PAC in the etiology of cardioembolic stroke.

Main Methods:

  • Retrospective study of ischemic stroke patients undergoing 24-hour Holter ECG.
  • Comparison of PAC frequency between noncardioembolic stroke (n=163), undetermined etiology stroke (n=24), and cardioembolic stroke (n=37) groups.
  • Analysis of the prevalence of frequent PAC (≥200 per 24 hours).

Main Results:

  • Patients with undetermined etiology stroke and cardioembolic stroke showed significantly more PAC than noncardioembolic stroke patients.
  • Frequent PAC were observed in 54% of undetermined etiology stroke patients and 48% of cardioembolic stroke patients, versus 20% in noncardioembolic stroke patients.
  • A higher proportion of patients with frequent PAC was found in groups with undetermined and cardioembolic stroke.

Conclusions:

  • Frequent PAC should be considered a potential marker for masked paroxysmal atrial fibrillation.
  • Frequent PAC may represent an underdiagnosed cause of cardioembolic stroke.
  • Identifying frequent PAC can improve stroke risk stratification and management strategies.
Abstract

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