Roya Sattarzadeh, Xavier Griffin.
Response/Recommendation: There is no evidence to indicate that the perioperative venous thromboembolism (VTE) prophylaxis of patients undergoing orthopaedic procedure and diagnosed with acute atrial fibrillation (AF) should be altered. However, according to the latest recommendations of the American Heart Association (AHA), the American College of Cardiology (ACC), the Heart Rhythm Society (HRS), and the European Society of Cardiology (ESC), the patients with AF, and high risk of embolic events should receive anticoagulation therapy.
Strength of Recommendation: Moderate.
Rationale: Based on published data, the risk of stroke in patients with AF increases1 in the presence of common stroke risk factors. The common risk factors for stroke have been evaluated and a clinical risk tool based on 7 variables: congestive heart failure, hypertension, age, diabetes mellitus, stroke, vascular disease, and female sex (CHA2DS2 VASC) score1-3. In all AF patients except with moderate- to severe-mitral stenosis or a mechanical heart valve, the CHA2DS2-VASc score is used to determine the risk of thromboembolic events for selecting an anticoagulant regimen regardless of the AF pattern (paroxysmal, persistent, permanent)3-5. For patients at high-risk for VTE events (defined as CHA2DS2 VASC score ≥ 2 in men and ≥ 3 in women), an anticoagulant therapy is recommended (Class I recommendation)1,3. In male patients with AF and CHA2DS2 VASC score = 2 and in females with CHA2DS2 VASC score = 1, individualized evaluations should be considered for anticoagulation therapy.
Some studies have recommended that in the absence of other AF risk factors, female patients carry a low risk of stroke and have proposed to consider ≥ 2 non-sex-related risk factors for female individuals to mark them as high risk for thromboembolic events3,6.
Based on ACC/AHA guideline for the management of patients with AF3, “valvular AF (defined as AF in the setting of moderate-to severe-mitral stenosis which potentially requires surgical intervention, or in the presence of a mechanical heart valve) is considered an indication for long-term anticoagulation with warfarin” while in patients with non-valvular AF, the CHA2DS2-VASc score is recommended for assessment of stroke risk. In score ≥ 2 in men or ≥ 3 or in women, oral anticoagulants including warfarin, dabigatran, rivaroxaban, apixaban or edoxaban are recommended. On the other hand, “bridging therapy with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) is recommended for patients with AF, and a mechanical heart valve undergoing procedures that require interruption of warfarin”.
Also, as mentioned above, according to 2020 ESC guidelines for the diagnosis and management of AF1, stroke risk assessment has been discussed in the setting of “AF in the absence of severe-mitral stenosis, or prosthetic heart valves because AF increases the risk of stroke five-fold”. Furthermore, it is mentioned that non-paroxysmal AF is associated with an increase in thromboembolism compared with paroxysmal AF (multivariable-adjusted hazard ratio [HR] 1.38; 95% confidence interval [CI] 1.19 – 1.61; p < 0.001). Compared to AF patients without valvular heart disease (VHD), “the risk of thromboembolism and stroke is increased among AF patients with VHD other than mitral stenosis, and mechanical heart prostheses, mostly owing to older age and more frequent comorbidities”. The similar CHA2DS2-VASc score risk stratification tool is recommended for stroke risk assessment to identify patients at stroke risk.
In conclusion, there is no specific difference in VTE prophylaxis of a patient diagnosed with acute AF in the perioperative period however these patients should be precisely evaluated with respect to common stroke risk factors via the CHA2DS2 VASC score and be treated with appropriate anticoagulant regimen in high-risk conditions. Otherwise, they should be evaluated individually to assess the perioperative risk of VTE.
1. Hindricks G, Potpara T, Dagres N, Arbelo E, Bax JJ, Blomström-Lundqvist C, Boriani G, Castella M, Dan G-A, Dilaveris PE. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS) The Task Force for the diagnosis and management of atrial fibrillation of the European Society of Cardiology (ESC) Developed with the special contribution of the European Heart Rhythm Association (EHRA) of the ESC. European heart journal. 2021;42(5):373-498.
2. Lip GY, Nieuwlaat R, Pisters R, Lane DA, Crijns HJ. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation. Chest. 2010;137(2):263-72.
3. January CT, Wann LS, Calkins H, Chen LY, Cigarroa JE, Cleveland JC, Ellinor PT, Ezekowitz MD, Field ME, Furie KL. 2019 AHA/ACC/HRS focused update of the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Journal of the American College of Cardiology. 2019;74(1):104-32.
4. Ahmad Y, Lip GY, Apostolakis S. New oral anticoagulants for stroke prevention in atrial fibrillation: impact of gender, heart failure, diabetes mellitus and paroxysmal atrial fibrillation. Expert review of cardiovascular therapy. 2012;10(12):1471-80.
5. Hohnloser SH, Duray GZ, Baber U, Halperin JL. Prevention of stroke in patients with atrial fibrillation: current strategies and future directions. European Heart Journal Supplements. 2008;10(suppl_H):H4-H10.
6. Nielsen PB, Skjøth F, Overvad TF, Larsen TB, Lip GY. Female sex is a risk modifier rather than a risk factor for stroke in atrial fibrillation: should we use a CHA2DS2-VA score rather than CHA2DS2-VASc? Circulation. 2018;137(8):832-40.