Related Experiment Video
Updated: Jun 18, 2026
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Delayed detection of atrial fibrillation after ischemic stroke
Hooman Kamel1, Kennedy R Lees, Patrick D Lyden
1Department of Neurology, University of California, San Francisco, CA, USA.
Insights
Delayed detection of atrial fibrillation (AF) after ischemic stroke is common. Current screening methods may miss underlying AF in many patients, highlighting a need for improved detection strategies.
Area of Science:
- Cardiology
- Neurology
- Clinical Trials
Background:
- Atrial fibrillation (AF) detection post-stroke is crucial for anticoagulation and recurrent stroke prevention.
- Optimal methods for detecting paroxysmal AF after ischemic stroke remain undefined.
- This study aimed to determine the rate, timing, and predictors of delayed AF detection.
Purpose of the Study:
- To characterize the incidence, delay, and associated risk factors for detecting atrial fibrillation (AF) in patients following ischemic stroke.
- To evaluate the effectiveness of current screening protocols in identifying underlying paroxysmal AF.
Main Methods:
- Analysis of 2504 patients from placebo arms of acute ischemic stroke trials (Virtual International Stroke Trials Archive).
- Exclusion of patients with prior AF history or baseline ECG evidence of AF.
- Kaplan-Meier survival analysis for time to AF detection and Cox proportional hazards analysis for risk factors.
Main Results:
- Atrial fibrillation (AF) was detected in 6.9% of patients (174/2504).
- In 68% of cases, AF was detected over 48 hours post-stroke presentation.
- Predictors of delayed AF detection included older age, female sex, congestive heart failure, and absence of hypertension.
Conclusions:
- Delayed detection of atrial fibrillation (AF) is prevalent in patients monitored after ischemic stroke.
- Existing screening methods appear insufficient for detecting paroxysmal AF in a significant number of stroke patients.
- Further research is needed to optimize AF detection strategies in this population.
Background:
Detection of atrial fibrillation (AF) after ischemic stroke is important because anticoagulation is indicated to reduce the risk of recurrent stroke. However, no consensus exists about the optimum method for detecting underlying paroxysmal AF not apparent on presentation with stroke. The aim of this study was to characterize the rate, timing, and predictors of delayed detection of AF after stroke.
Methods:
The Virtual International Stroke Trials Archive provided data from 3464 patients in the placebo arms of 4 clinical trials of therapies for acute ischemic stroke. Patients who had AF by history or on the baseline electrocardiogram were excluded. Electrocardiograms were obtained routinely and as clinically indicated. The time to detection of AF was evaluated using Kaplan-Meier survival statistics. Cox proportional hazards analysis was used to evaluate risk factors for AF.
Results:
Among 2504 qualifying patients, AF was detected in 174 (6.9%; 95% confidence interval [CI] 6.0%-8.0%). In 68% of patients, AF was detected more than 48 hours after presentation. Detection of AF was associated with increasing age (hazard ratio [HR] 1.6/decade; 95% CI 1.4-1.9; P < .005), female sex (HR 1.7; CI 1.2-2.4; P < .005), congestive heart failure (HR 1.9; CI 1.1-3.4; P = .02), and the absence of hypertension (HR 1.6; CI 1.1-2.2; P = .01).
Conclusions:
Delayed detection of AF was common in this large cohort of patients carefully monitored after ischemic stroke. Current methods of screening may fail to detect underlying paroxysmal AF in a substantial proportion of patients.
More Related Videos
Related Concept Videos
01:30Acute Coronary Syndrome III: Diagnostic Studies
01:26Transient Ischemic Attack l: Introduction