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Clinical utility and prognostic implications of the 4S-AF scheme: Report from Asia Pacific Heart Rhythm Society
Tze-Fan Chao1,2, Hung-Fat Tse3, Wee-Siong Teo4
1Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
Insights
The 4S-AF classification effectively characterizes atrial fibrillation (AF) risk in Asian patients. Applying this scheme for treatment significantly reduces adverse clinical outcomes, supporting its use in AF management.
Area of Science:
- Cardiology
- Clinical Research
- Atrial Fibrillation Management
Background:
- The 4S-AF classification scheme (stroke risk, symptoms, AF burden, substrate) is recommended by ESC guidelines for AF patient evaluation.
- This scheme aims to standardize AF characterization and risk assessment.
Purpose of the Study:
- To assess the utility and prognostic value of the 4S-AF scheme in a large, prospective Asian registry.
- To determine if 4S-AF characterization aids in predicting adverse events in Asian patients with atrial fibrillation.
Main Methods:
- Analysis of 3586 patients from the Asia Pacific Heart Rhythm Society (APHRS) registry with available left atrial dimension and EHRA symptom scores.
- Calculation of the 4S-AF score and evaluation of its association with a 1-year composite endpoint of thromboembolic events, stroke, heart failure, ACS, CAD, and mortality.
Main Results:
- A majority of patients (86.7%) were classified as 'non-low risk' for stroke.
- Higher 4S-AF scores correlated with increased risk of adverse clinical events, with tertile 3 (6-9 points) showing a 3.5-fold increase.
- Appropriate treatment guided by the 4S-AF scheme was associated with a significantly lower risk of composite clinical outcomes (aOR 0.384).
Conclusions:
- The 4S-AF scheme effectively relates to adverse event risk in Asian AF patients.
- Management based on the 4S-AF classification improves clinical outcomes, supporting its adoption in Asian populations.
- The study validates the 4S-AF scheme for characterizing and managing atrial fibrillation in Asian patients.
Background:
The 4S-AF classification scheme comprises of four domains (stroke risk [St], symptoms [Sy], severity of atrial fibrillation (AF) burden [Sb] and substrate [Su]), which has been recommended in the 2020 ESC guidelines to characterize and evaluate patients with AF.
Objectives:
We aimed to determine whether the 4S-AF scheme would be useful for AF characterization and provides prognostic information in a large contemporary prospective Asian registry conducted by the Asia Pacific Heart Rhythm Society (APHRS).
Methods:
Among 4666 patients enrolled in APHRS registry, 3586 of them whose data about left atrial (LA) dimension and European Heart Rhythm Association (EHRA) symptom score were available have constituted as the study population. The 4S-AF score was calculated as the sum of each domain with a maximum score of 9. The clinical endpoint was defined as the 1-year composite risk of any thromboembolic event, ischaemic stroke, heart failure, acute coronary syndrome, significant coronary artery disease requiring coronary intervention and all-cause mortality.
Results:
Based on the 4S-AF domains, 86.7% were 'non-low risk' for stroke; 94.3% had EHRA Class I-II, 48.5% were newly diagnosed or paroxysmal AF; and only 8.4% had no cardiovascular risk factors or LA enlargement. The risk of clinical events was higher in patients who were 'non-low risk' for stroke (aOR 2.175, 95% CI 1.060-4.461), with permanent AF (aOR 1.579, 95% CI 1.106-2.225) and increasing points for substrate (aORs 2.376-4.968 from score 2 to 4). When compared to the first tertile of 4S-AF score (0-3 points), patients in the second tertile (4-5 points) had approximately 2.5-fold increase in adverse events (OR 2.478, 95% CI 1.678-3.661, p < .001), while those in the third tertile (6-9 points), had a 3.5-fold increase (OR 3.484, 95% CI 2.322-5.226, p < .001), both without significant differences between the 5 participating countries (p for interaction > .05). If all 4S-AF domains were appropriately treated, this was associated with a lower risk of composite clinical outcomes (aOR 0.384, p < .001; p for interaction for different countries = .234).
Conclusions:
Categorization according to the 4S-AF scheme can be related to the risk of the composite adverse event rate in Asian AF patients, and appropriate treatments based on the 4S-AF scheme resulted in better clinical outcomes. These observations support the characterization and management according to the 4S-AF scheme in Asian patients.
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