The recent publication of the European Society of Cardiology (ESC) and the American College of Cardiology (ACC) guidelines provided an important update on multiple aspects of the management of atrial fibrillation (AF).
However, these guidelines differ in terms of management and recommendation levels.
As it might be expected, most differences arose in intermediate cases—both guidelines usually coincide when it comes to extreme cases.
Using the CHA2DS2-VASc score is recommended in both guidelines to calculate the risk for stroke and to decide on the indication of anticoagulant agents. Both recommend using oral anticoagulant agents in patients with high thromboembolic risk (score of ≥2 in men and ≥3 in women). Furthermore, both ban the use of anticoagulant agents in low risk patients.
Patients with intermediate risk (score of 1 in men and 2 in women) is where differences appear: according to the ESC, using anticoagulant agents “should” be considered in these cases (recommendation IIa, evidence level B), while the ACC says it “might” be considered (IIb-C).
Other differences arise in the recommendations for peri-cardioversion anticoagulation. According to the ESC guidelines, anticoagulant agents should be considered as soon as possible once performing a cardioversion is decided (IIa-B). The ACC indicates that not anticoagulating could be considered when AF has lasted less than 48 hours and the CHA2DS2-VASc score is low (0 in men and 1 in women).
As regards patients with a high score, both guidelines agree that anticoagulation should be continued for a long period after cardioversion. Here, differences are subtle: the ESC indicates anticoagulation could be skipped when AF has lasted less than 24 hours (48 hours for the ACC) in low-risk patients.
Discrepancies continue when referring to catheter ablation. Europe prioritizes the high success rate of ablation by recommending the procedure in those with antiarrhythmic drugs-resistant (or intolerant) persistent AF beyond the risk of recurrence. The ACC considered this procedure as a viable option in select patients.
AF in a setting of impaired ventricular function has shown superiority to medical treatment, reducing mortality and hospitalizations. For the ACC, these studies are small and in highly selected populations, so it calls for more studies to confirm these findings, although ablation may be a reasonable option (IIb-B). The ESC highly recommends ablation in patients with impaired ventricular function.
Another controversy arises when these patients undergo coronary angioplasty. American guidelines recommend a triple therapy (aspirin, P2Y12 inhibitor, and oral anticoagulation) for 4-6 weeks, and then continuing with anticoagulation therapy plus a P2Y12 inhibitor in patients at high risk for stroke.
The ESC shows a greater fear of bleeding. Less than one week of triple therapy for patients at low risk of stent thrombosis, and less than one month for those at high risk of stent thrombosis.
Much of the differences between the two documents arise from the lack of evidence that still exists on some aspects of AF. Other differences could be due to the different publication years (2020 vs. 2019).
Reference: Alireza Oraii et al. Eur Heart J. 2021 May 14;42(19):1820-1821. doi: 10.1093/eurheartj/ehaa1098.