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Page 10 of 15 Tummala et al. Vessel Plus 2022;6:17 https://dx.doi.org/10.20517/2574-1209.2021.114

NEW-ONSET POAF PREVENTION
The onset of atrial fibrillation after a SAVR and TAVR procedure is an adverse outcome that can be
prevented with proper medical management. Unfortunately, there is limited literature on how to give
prophylaxis best to prevent new-onset POAF. Like a clinical case with pre-existing non-surgical atrial
fibrillation, patients undergoing SAVR and TAVR procedures can receive antiarrhythmics peri-operatively
to decrease the likelihood of new-onset atrial fibrillation. The most commonly used medications for
prophylaxis include amiodarone and sotalol. Another management option that can be performed post-
[32]
operatively would be prophylactic atrial pacing for at least 24 h .

NEW-ONSET POAF ANTICOAGULATION AND TREATMENT
SAVR
New-onset atrial fibrillation following SAVR and TAVR has been shown to be an independent predictor of
mortality and thrombotic events, such as stroke [45,54] . The current recommendations for antiplatelet and
anticoagulant therapy following aortic valve replacement come from the American Heart
Association/American College of Cardiology (AHA/ACC) and the European Society of
Cardiology/European Association for Cardio-Thoracic Surgery (ESC/EACTS). Following SAVR, the
AHA/ACC recommends lifelong daily aspirin 75-100 mg for all bioprosthetic valve patients and daily
aspirin 75-100 mg only for mechanical valve patients with antiplatelet indications. The AHA/ACC also
recommends a vitamin K antagonist for 3 to 6 months in bioprosthetic valve patients with a low risk of
bleeding. The ESC/EACTS recommends aspirin 75-100 mg/day and an oral anticoagulant for the first 3
months following the procedure in all patients, and lifelong oral anticoagulation in patients with indications
[55]
for it, such as a hypercoagulable state, venous thromboembolism, and atrial fibrillation .
Given the association between POAF and thrombosis, clinical trials have examined the impact of
anticoagulation treatment following aortic valve replacement. However, very few studies have examined the
role of antithrombotic treatment after SAVR. One study to do so is a 2019 paper by Chakravarty et al. ,
[56]
which found that a greater proportion of patients after SAVR, in comparison to TAVR patients, were
discharged home on anticoagulant and antiplatelet therapy. The study found no difference in aortic valve
mean gradient or area, major or minor bleeding, rehospitalization, aortic valve intervention, or death
between SAVR patients discharged with or without anticoagulant treatment. However, the one major
difference was that patients discharged with anticoagulant therapy had significantly decreased stroke rates
compared to those not on anticoagulant treatments (1.7% vs. 5.5%). Given the improvement in stroke risk
and lack of increased bleeding risk, the study found it safe and beneficial to initiate anticoagulation therapy
in patients following SAVR. While this study does not specifically examine SAVR in the setting of atrial
fibrillation, lifelong anticoagulant therapy is indicated after SAVR if POAF develops . Discontinuing
[57]
anticoagulant therapy within the first 3 to 6 months after surgery has been associated with an increased risk
of stroke and cardiovascular events in patients with unknown atrial fibrillation status .
[58]

TAVR
Following TAVR, the AHA/ACC recommends lifelong aspirin 75-100 mg/day, clopidogrel 75/day for 6
months, and a vitamin K antagonist for at least 3 months if there is a low bleeding risk. In addition, the 2017
ESC/EACTS guidelines recommend dual antiplatelet therapy for the first 3 to 6 months, followed by single
platelet therapy. For patients with indications for anticoagulation, including atrial fibrillation, the guidelines
recommend lifelong oral anticoagulation .
[55]
Numerous studies have examined the impact of anticoagulation treatment on patients after TAVR
[29]
procedures. A study by Amat-Santos et al. found that 40% of TAVR patients with POAF who did not