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Rove et al. Vessel Plus 2022;6:55 https://dx.doi.org/10.20517/2574-1209.2021.133 Page 5 of 9

and magnesium. The non-pharmacologic interventions included atrial pacing and posterior
pericardiotomy. Reviewing 118 studies that included 17,364 patients, all of these interventions were found
to significantly reduce the rate of POAF after cardiac surgery compared with a placebo control [Table 2].
Beta-blockers and sotalol were documented to have similar efficacy. In six trials, amiodarone, atrial pacing
and posterior pericardiotomy were also found to be effective for POAF reduction. In this analysis,
magnesium was shown to prevent POAF; however, the impact of magnesium may be slightly less than that
of the other pharmacological agents. Importantly, the additional investigation could establish more
extensive professional society-based recommendations for POAF interventions.

POAF treatment
When POAF is encountered postoperatively, beta blockade (Class I level of evidence A),
nondihydropyridine calcium channel blockers (Class I level of evidence B), and antiarrhythmic agents
(Class II, level of evidence B) are recommended to convert POAF to sinus rhythm and/or rate control in
atrial fibrillation. Guidelines also recommend it is reasonable to restore sinus rhythm with direct-current
[21]
cardioversion in patients with POAF (Class IIa, level of evidence B) . In addition to rhythm and rate
control, guidelines support anticoagulation in patients with POAF (Class IIa, level of evidence B) [21,22] .

Contemporary practice patterns of cardiac surgeons were recently examined; based on these findings,
postoperative care teams appeared to aim to achieve rhythm control and avoid anticoagulation.
Matos et al. used STS ACSD data from 2011-2018 to evaluate discharge medications in patients receiving
[24]
an isolated CABG who experienced POAF. Anticoagulation for post-CABG AF had a greater than 4-fold
increase in the risk of major bleeding. Only 26% of those with POAF were discharged on anticoagulation
despite a mean CHA2DS2-VASc score of 3.2. In addition, more than three-quarters of patients with post-
CABG AF were discharged on amiodarone, and 57% of the total population received amiodarone without
concomitant anticoagulation. The manuscript does not report the duration of POAF nor whether left atrial
appendage occlusion was performed. Compared to the number of patients discharged on amiodarone,
cardiac surgeons did not start anticoagulation for atrial fibrillation in at least 1 out of 4 postoperative
[2]
patients. The randomized control trial by Gillinov et al. comparing rate- vs. rhythm-control in cardiac
surgery patients with POAF showed, in intention-to-treat analysis, no difference between groups in days of
hospitalization, thromboembolic or bleeding events in the first 60 days . Patients who remained in AF or
[2]
had recurrent AF were “recommended” to be anticoagulated with warfarin. Anticoagulation with warfarin
[24]
was higher in this trial (43%) compared to what Matos et al. reported (26%) but still, not even the majority
of patients were anticoagulated, and no CHA2DS2-VASc scores were reported. With limited randomized
controlled trial data on rate- vs. rhythm-control and the benefit of anticoagulation, surgeon-based patterns
appear to favor early rhythm control for new-onset POAF patients in a presumed attempt to avoid the
bleeding risk associated with anticoagulation, even with side effects from antiarrhythmic medication
occurring in as many as 15% of patients . Given this controversy, additional research appears warranted to
[2]
identify the risks and benefits associated with POAF management in cardiac surgery patients [2,25-27] . Pending
additional data-driven findings, future clinical POAF practices may be better aligned with professional
society guidelines.

POAF and the role of the left atrial appendage
Left atrial appendage (LAA) closure is a non-pharmacologic strategy for stroke prevention; historically,
LAA has been identified as the main source of cardiac thrombi leading to arterial embolization and
[28]
stroke . The recent meta-analysis by Martín et al. reported that a preoperative atrial fibrillation burden
[24]
greater than 70% benefits from LAA closure during cardiac surgery, although across these studies, the LAA
closure methods used were highly variable. In this meta-analysis, overall, there was minimal use of
epicardial occlusion-which has been documented as the most durable obliteration method . In a meta-
[28]