Background: The role of short-lasting (<30 sec) runs of atrial fibrillation (AF) in ischemic stroke pathophysiology is currently unknown. Although these non-sustained attacks are considered as a risk factor for future development of longer lasting, classical AF episodes, prior research has highlighted that associated clinical stroke features are not entirely similar between these two types of arrhythmias. In this study we determined the prevalence of short-lasting AF in stroke-free controls and compared it to a consecutive series of ischemic stroke patients.
Methods: A total 235 controls, without any prior history stroke or AF, were evaluated with ECG and 24-hour Holter monitoring for the presence of <30-sec or ≥30-sec lasting AF episodes. The results were compared to a consecutive series of ischemic stroke patients without prior history of AF (n=456). Univariate and multivariate analyses were performed to determine demographic and cardiovascular factors related to <30-sec lasting AF and its association with ischemic stroke.
Results: Expectedly, the frequency of newly diagnosed ≥30-sec lasting AF, detected either on ECG or Holter monitoring, was significantly higher in patients with ischemic stroke (18% vs. 2%; p<0.01). Non-sustained AF was positively related to old age (p<0.01), female gender (p=0.01) and hypertension (p<0.01) in univariate analyses. In multivariate analyses, after adjustment for demographic and cardiovascular risk factors, presence of non-sustained AF was significantly higher among both cryptogenic (OR 1.78; 95% CI 1.02-3.10) and non-cryptogenic (OR 1.84; 95% CI 1.15-2.94) stroke patients with respect to controls.
Conclusion: Our study shows a higher prevalence of non-sustained AF episodes in ischemic stroke patients in comparison to controls. Whether this cross-sectional association translates into causality in terms of stroke pathophysiology will be the subject of future studies.