The 2024 European Society of Cardiology (ESC) guidelines on managing atrial fibrillation (AF) provide new insights into patient care. Similar to previous ESC guidelines, these guidelines reinforce a stepwise comprehensive approach. They offer recommendations not only on treating tachyarrhythmia, prioritizing rhythm control, but also stress the importance of identifying and managing cardiovascular risk factors (CVRF) as essential components of comprehensive AF management. Throughout the guidelines, patients remain the focal point of AF management, highlighting the need to educate patients and caregivers to optimize decision-making and facilitate therapeutic approaches, recommending multidisciplinary teams and telemedicine for these purposes. 

This guideline summary shares the main changes in clinical practice recommendations for their prompt application in patient management. 

The main updates compared to the 2020 ESC guidelines include the emphasis on comprehensive CVRF management, the importance of early rhythm control strategies, the change in CHA2DS2-VA score nomenclature with the removal of the gender criterion, and the use of catheter ablation as a first-line rhythm control strategy for patients with paroxysmal AF. 

Key Messages: 

Below are the key topics addressed in the guidelines, highlighting those expected to have the greatest impact on daily clinical practice due to new scientific evidence. 

1. Unlike the 2023 American Heart Association (AHA) guidelines, which view AF as a continuum, these guidelines retain the classic classification based on duration (first diagnosis, paroxysmal, persistent, and permanent), emphasizing frequent reassessment due to the disease’s variable nature. Nonetheless, the guidelines acknowledge the need for classification based on pathophysiology and its influence on individual AF management. 
2. For diagnosis, confirmation of AF with a 12-lead electrocardiogram (ECG) is still required; if detected via a device, it should enable ECG tracing and require physician evaluation for confirmation. 
3. A stepwise management of AF is recommended. The 2020 ESC guidelines previously referred to this as the ABC protocol, now updated to AF-CARE, encompassing “C” for comorbidity and CVRF management, “A” for anticoagulation to prevent strokes and embolisms, “R” for symptom reduction via heart rate and rhythm control, and “E” for dynamic process assessment. 
4. C: Emphasis is placed on the identification and management of CVRF as an integral part of AF care, aimed at both preventing AF and reducing its progression or adverse effects. Detailed guidance is provided on blood pressure, glucose control, exercise, managing obstructive sleep apnea, reducing alcohol intake (<30g/week), and intensive weight management for overweight or obese patients, with a target of a 10% reduction in body weight. Additionally, it is recommended that, in the absence of specific evidence for this subgroup, heart failure (HF) management in patients with reduced or preserved ejection fraction (EF) should follow standard HF treatment protocols. This includes achieving euvolemia and initiating SGLT2 inhibitors in symptomatic patients, regardless of EF. 
5. A: Anticoagulation (AC) is still recommended for patients with high ischemic risk, defined by validated scales such as CHA2DS2-VA. A notable update in these guidelines is the removal of the gender criterion from the CHA2DS2-VA scale, as female sex is now considered a risk modifier rather than an independent risk factor. CHA2DS2-VA ≥ 2 indicates a high thromboembolic risk, while CHA2DS2-VA =1 can be regarded as a high-risk factor. 
6. One of the main evidence gaps in AC remains the management of subclinical AF. Despite recent data from the NOAH and ARTESIA studies, the guidelines provide only a tentative recommendation for AC in this patient population. The initiation of direct oral anticoagulants (DOAC) may be considered (IIb) in patients with high ischemic risk but without major bleeding risk, although specific thresholds for duration or burden of subclinical AF are not yet defined. 
7. For the type of anticoagulant, DOACs are prioritized over vitamin K antagonists (VKA), except in cases of moderate-to-severe mitral stenosis or mechanical heart valves. It is recommended that patients over 75 years and those on multiple medications with stable INR levels remain on VKAs rather than switching to DOACs, as the latter have been associated with increased major bleeding in this demographic. 
8. A level IA recommendation is now given for surgical left atrial appendage (LAA) closure combined with AC in patients with AF undergoing cardiac surgery. This recommendation is based on the findings of the LAAOS III trial, which showed a 33% reduction in stroke or systemic embolism risk in anticoagulated AF patients with LAA closure. Evidence for LAA closure in hybrid ablation is still limited, but ongoing studies are investigating this application. 
9. R: Similar to AHA guidelines, early rhythm control is advocated, prioritizing sinus rhythm maintenance and AF burden reduction. 
10. In terms of acute management of AF patients, the only difference from previous guidelines is a shorter safety interval (reduced from 48 to 24 hours from AF onset) for performing cardioversion in patients without AC or imaging to rule out LAA thrombi. 
11. Catheter ablation for patients with paroxysmal AF is now given a level IA recommendation (previously IIa) as first-line therapy for rhythm control, aiming to reduce symptoms, recurrence, and disease progression. This is supported by recent studies such as STOP-AF and EARLY-AF, which demonstrate the superiority of cryoablation over antiarrhythmic drugs. The evidence for catheter ablation in persistent AF is less conclusive, leading to a stronger emphasis on electrical cardioversion for evaluating the benefits of sinus rhythm restoration, followed by medical management if necessary. For persistent AF, first-line catheter ablation has a recommendation level of IIa. 
12. The IB recommendation for catheter ablation in HF patients with reduced EF and suspected tachycardia-induced cardiomyopathy remains. 
13. Hybrid ablation is considered (IIa) for persistent AF refractory to medical treatment, focusing on symptom relief, recurrence reduction, and progression prevention. It is less strongly recommended for paroxysmal AF. 
14. Surgical ablation is advised for patients with AF undergoing mitral surgery, with a lower recommendation level for non-mitral proced08ures. Posterior pericardiotomy may be considered for AF prevention in patients undergoing cardiac surgery. 
15. E: Regular assessment and reassessment to detect structural and functional cardiac changes, as well as to evaluate comorbidity development, treatment adherence, improvement in functional capacity, and quality of life. Reassessment is recommended at 6 months post-event and annually or based on clinical presentation thereafter. 
16. Finally, recommendations are provided for managing special cases such as pregnancy, acute coronary syndromes, and stroke. 

With respect to ablation, these guidelines highlight its central role. Like previous AHA guidelines, they emphasize early rhythm control and ablation as first-line therapy to achieve this goal. Therefore, a summary of the evidence supporting these recommendations is presented below. The early rhythm control strategy is based on findings from the EAST-AFNET 4 study, which demonstrated better cardiovascular outcomes over 5 years with early rhythm control achieved through either medical therapy or ablation compared to conventional rate control. To determine the best approach for rhythm control, the EARLY-AF and STOP AF studies compared endocardial ablation with antiarrhythmic drugs, showing lower tachyarrhythmia recurrence and improved quality of life in paroxysmal AF patients undergoing ablation compared to medical therapy. Additionally, the CASTLE-AF and CASTLE-HTX studies support ablation as first-line therapy in HF patients with reduced EF, even in advanced stages, reducing morbidity and mortality. This evidence underscores the importance of ablation in selected patients. Hybrid ablation is primarily recommended for persistent AF refractory to medical therapy, aiming to decrease symptoms, recurrence, and progression to permanent AF. 

As a final summary, a comparative table is provided for ablation recommendation levels according to the ESC 2020, AHA 2023, and ESC 2024 guidelines, offering a visual overview of the increased recommendation for ablation supported by recent evidence. 

REFERENCES: 

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