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Page 2 of 15 Tummala et al. Vessel Plus 2022;6:17 https://dx.doi.org/10.20517/2574-1209.2021.114

Keywords: SAVR, TAVR, atrial fibrillation

INTRODUCTION
Atrial fibrillation (AF) is a common comorbidity among patients undergoing cardiac surgery. In patients
with aortic stenosis (AS), pre-existing AF is noted to be associated with an increased risk of heart failure,
mortality, and stroke . Symptomatic AS can further contribute to hemodynamic complications and can be
[1]
fatal despite medical management as the 5-year mortality rate is 50%-60%, and the 10-year mortality rate is
90% . Procedures such as surgical aortic valve replacement (SAVR) and transcatheter aortic valve
[2,3]
replacement (TAVR) can treat aortic stenosis. However, these procedures are associated with high rates of
pre-operative and post-operative atrial fibrillation (POAF). AF is among the most common post-operative
outcomes following cardiac surgery (10%-40%) and is recognized to be a significant predictor of adverse
clinical outcomes. In this review, we highlight the relevant literature regarding incidence rates, predictors,
management, and prevention of preoperative and postoperative AF following SAVR/TAVR procedures.

METHODS
A literature search of relevant articles was conducted via the following PubMed, Medline, and EMBASE
search: “SAVR” OR “surgical aortic valve replacement” OR “TAVR” or “transcatheter aortic valve
replacement” AND “atrial fibrillation” OR [atrial fibrillation (MeSH Terms)]. Further, a Web of Science
backward literature search was conducted to identify relevant literature.

PREOP AF RISKS
Etiology
Atrial fibrillation is commonly associated with aortic stenosis. While the exact pathophysiological
mechanism behind the etiology of atrial fibrillation in aortic stenosis is unclear, one leading theory involves
the left ventricular (LV) response. It is believed that aortic stenosis leads to LV outflow obstruction, which
results in left atrial and LV pressure overload. The pressure overload, in turn, leads to myocardial fibrosis
and LV hypertrophy, in addition to increased diastolic filling pressure, impaired relaxation, and left atrial
dilation. These changes lead to increased left atrial pressure and further systolic and diastolic dysfunction,
ultimately resulting in atrial fibrillation .
[1,4]
Predictors
The exact predictors of pre-existing atrial fibrillation in SAVR patients are unknown. However, some
predictors of pre-existing atrial fibrillation in TAVR patients include the presence of moderate to severe
[5]
mitral regurgitation, moderate to severe tricuspid regurgitation, and pulmonary hypertension . Other
predictors of TAVR with atrial fibrillation include older age, female gender, and comorbidities such as
diabetes, chronic lung disease, congestive heart failure, chronic renal disease, anemia, arthritis,
hypothyroidism, and peripheral vascular disease .
[6]

PREOP AF RATES
SAVR
The association between atrial fibrillation and aortic valve replacement has been studied in the literature,
and there seems to be a correlation between pre-existing atrial fibrillation and subsequent aortic valve
replacement. Regarding SAVR particularly, atrial fibrillation has been seen in 6.3%-35.2% of patients prior
to surgery [Table 1].