Title:A Simple Score for Predicting Paroxysmal Atrial Fibrillation in Patients
with Embolic Stroke of Undetermined Source in a Tunisian Cohort Study
Volume: 21
Issue: 2
Author(s): Sana Ben Amor*, Assil Achour, Aymen Elhraiech, Emna Jarrar, Hela Ghali, Ons Ben Ameur, Nesrine Amara, Anis Hassine, Houyem Saied, Eleys Neffati and Didier Smadja
Affiliation:
- Stroke Unit, Department of Neurology, Centre Hospitalier Sahloul, Sousse, Tunisia
- Faculty of medicine Ibn El Jazzar,
University of Sousse, Sousse, Tunisia
Keywords:
Cryptogenic embolism stroke, paroxysmal atrial fibrillation, 12-lead ECG, holter ECG, echocardiography transthoracic, anticoagulants.
Abstract:
Background: The annualized recurrent stroke rate in patients with Embolic Stroke of
Undetermined Source (ESUS) under antiplatelet therapy is around 4.5%. Only a fraction of these
patients will develop atrial fibrillation (FA), to which a stroke can be attributed retrospectively.
The challenge is to identify patients at risk of occult AF during follow-up.
Objective: This work aims to determine clinical factors and electrocardiographic and ultrasound
parameters that can predict occult AF in patients with ESUS and build a simple predictive score
applicable worldwide.
Methods: This is a single-center, registry-based retrospective study conducted at the stroke unit
of Sahloul University Hospital, Sousse, Tunisia, between January 2016 and December 2020.
Consecutive patients meeting ESUS criteria were monitored for a minimum of one year, with a
standardized follow-up consisting of outpatient visits, including ECG every three months and a
new 24-hour Holter monitoring in case of palpitations. We performed multivariate stepwise regression
to identify predictors of new paroxysmal AF among initial clinical, electrocardiographic
(ECG and 24-hour Holter monitoring) and echocardiographic parameters. The coefficient of
each independent covariate of the fitted multivariable model was used to generate an integerbased
point-scoring system.
Results: Three hundred patients met the criteria for ESUS. Among them, 42 (14%) patients
showed at least one episode of paroxysmal AF during a median follow-up of two years. In univariate
analysis, age, gender, coronary artery disease, history of ischemic stroke, higher NIHSS
at admission and lower NIHSS at discharge, abnormal P-wave axis, prolonged P-wave duration,
premature atrial contractions (PAC) frequency of more than 500/24 hours, and left atrial (LA)
mean area of more than 20 cm2 were associated with the risk of occurrence of paroxysmal AF.
We proposed an AF predictive score based on (1.771 x NIHSS score at admission) + (10.015 x
P-wave dispersion; coded 1 if yes and 0 if no) + (9.841x PAC class; coded 1 if ≥500 and 0 if no)
+ (9.828x LA class surface; coded 1 if ≥20 and 0 if no) + (0.548xNIHSS score at discharge) +
0.004. A score of ≥33 had a sensitivity of 76% and a specificity of 93%.
Conclusion: In this cohort of patients with ESUS, NIHSS at both admission and discharge, Pwave
dispersion, PAC≥500/24h on a 24-hour Holter monitoring, and LA surface area≥20 cm2
provide a simple AF predictive score with very reasonable sensitivity and specificity and is applicable
almost worldwide. An external validation of this score is ongoing.
