Andrea Winkel, Pharm.D.; Tawnie McGraw, Pharm.D.; Anna Boik, Pharm.D.; Juan Reyes III, Pharm.D., PGY1 Residents at Mercy Health Muskegon
Due to emerging evidence since the 2014 guidelines, a focused update for the management of patients with atrial fibrillation (AF) was released by the American College of Cardiology (ACC), the American Heart Association (AHA), and the Heart Rhythm Society (HRS) in July 2019. This focused update removed the ambiguity associated with the 2014 guidelines and has provided a more objective approach to determining a patient’s need for anticoagulation. Key components of the update include the incorporation of recently approved medications such as edoxaban and andexanet alfa, precise treatment recommendations utilizing CHA2DS2-VASc scores based on sex, and non-pharmacological interventions. This revision maintains consistency with the use and definition of "anticoagulant" versus "antithrombotic" throughout the document.
The focused update now defines antithrombotic as the "combination of an anticoagulant and an antiplatelet." Many sections were revised to use the term "anticoagulant" when "antithrombotic" had previously been stated. This removes the possibility for multiple interpretations.
Some of the biggest changes in recommendations occurred in the Risk-based Anticoagulant Therapy section. The update removed the distinction between valvular and non-valvular atrial fibrillation and instead gives precise recommendations based on sex and CHA2DS2-VASc score for all patients with atrial fibrillation excluding two groups: those with moderate-to-severe mitral stenosis or mechanical heart valve. Previously, the 2014 guidelines recommended anticoagulants if the CHA2DS2-VASc score was > 2 for men and women. The 2019 update now recommends the use of anticoagulants as summarized in Table 1.
The list of recommended anticoagulants has also been updated to include edoxaban, which was approved after the 2014 guidelines were published. The list of anticoagulants now includes warfarin and novel oral anticoagulants (NOACs) including dabigatran, rivaroxaban, apixaban and edoxaban. A class I (strong) recommendation has also been made to use NOACs over warfarin in patients with atrial fibrillation (excluding patients with moderate-to-severe mitral stenosis and mechanical heart valve).
Along with this new recommendation came an additional class I (strong) recommendation for the assessment of both renal and hepatic function before initiating a NOAC and at least annually while on NOAC therapy. Edoxaban has been included throughout the updated guidelines to reflect its current data outcomes. Edoxaban was not recommended in patients with end-stage renal disease (ESRD) or who are on dialysis, but the update recommends that it may be used if the creatinine clearance is between 15 to 50 mL/min. However, it is not currently approved for use in patients with a creatinine clearance < 30 mL/min or > 95 mL/min. Before the update, warfarin was the only recommended anticoagulant for patients with ESRD or who are on dialysis. Now, apixaban has been added as a recommendation in this population when the CHA2DS2-VASc score is > 2 in men or > 3 in women.
Other new recommendations highlight the benefits of weight loss and modification of risk factors in patients with atrial fibrillation to decrease symptoms, severity and frequency of atrial fibrillation episodes. More subtle changes were made throughout the update as well, including the omission of a goal INR range for patients with mechanical heart valves on warfarin. While warfarin is still the recommended anticoagulant for patients with mechanical heart valves, there is some limited evidence for lower INR goals with certain mechanical valves. NOACs were added to previous recommendations that had only included warfarin, such as surrounding cardioversion and in patients with concomitant acute coronary syndrome, atrial fibrillation and a CHA2DS2-VASc score > 2. Idarucizumab is now included as a class I (strong) recommendation for the reversal of dabigatran for urgent procedures or life threatening bleeding and andexanet alfa was given a class IIa (moderate) recommendation for the reversal of rivaroxaban and apixaban in the case of life-threatening bleeding.
Overall, the biggest change is the use of CHA2DS2-VASc scores along with sex to recommend anticoagulation for patients with atrial fibrillation. Also, studies that proved NOACs to be non-inferior or superior to warfarin were included to support the growing use of NOACs for use in preventing stroke and systemic embolism in patients with atrial fibrillation. In conclusion, the focused 2019 update of the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation helps to clarify previous evidence found and incorporated new data for future practice.
1. January C, Wann S, Calkins H et al. 2019 AHA/ACC/HRS focused update of the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation. J Am Coll Cardiol. 2019 July 9;74(1):104-132. Available from: http://www.onlinejacc.org/content/early/2019/01/21/j.jacc.2019.01.011?_ga=2.184713199.751774949.1563839778-458285286.1529684827
2. January C, Wann L, Alpert J, Calkins H, Cigarroa J, Cleveland J, et al. Circulation. 2014 Dec. 2;130(23):e199-267. Available from: https://www.ahajournals.org/doi/pdf/10.1161/CIR.0000000000000041