New STS guideline tackles the prevention of AFib after cardiac surgery
A new clinical guidance from the the Society of Thoracic Surgeons (STS) recommends being more aggressive with amiodarone and posterior pericardiotomy to prevent new-onset atrial fibrillation (AFib) after cardiac surgery.[1]
Cardiovascular Business spoke to Subhasis Chatterjee, MD, lead author of that guideline and director of the Thoracic Surgical ICU and ECMO Program at Baylor St. Luke's Medical Center, to learn more. He outlined key recommendations from the document, which was based on data found and reviewed by experts from the fields of cardiac surgery, cardiology, critical care and anesthesiology.
One reason this is such an important topic is the fact that post-operative AFib remains the most common complication following cardiac surgery. It occurs in up to 50% of patients.
"This is something that's more than just a nuisance," Chatterjee said. "We reviewed all of the existing guidelines, looked at all of the evidence that's been published and issued recommendations on how to both prevent and then manage new-onset AFib after cardiac surgery."
Amiodarone receives strongest recommendation to prevent post-op AFib
Among the guideline's most significant changes is a Class I recommendation for prophylactic amiodarone, making it the strongest medication recommendation in the guideline. Beta blockers received a Class IIa recommendation.
Chatterjee said concerns that amiodarone increase the risk of adverse effects such as bradycardia and heart block were not supported by the available evidence. A review of published studies found bradycardia occurred in only about 2-4% of patients and heart block in 1-2%, rates comparable to beta blockers.
While preoperative administration can be difficult in modern surgical practice, he said evidence shows postoperative initiation remains highly effective. At Baylor St. Luke's, patients without contraindications are routinely started on an amiodarone infusion immediately upon arrival in the intensive care unit following surgery.
The guideline suggests a cumulative dose of approximately 3-6 grams provides preventive benefit.
Simple surgical technique may reduce AFib risk
The guideline also includes a Class IIa recommendation for posterior pericardiotomy, a surgical technique that requires creating a small opening in the posterior pericardium during cardiac surgery.
Her said the opening allows blood that would otherwise accumulate around the heart to drain into the left chest. Chatterjee said this reduces inflammation of the epicardial surface that can trigger AFib, which most commonly develops two to four days after surgery.
According to Chatterjee, the procedure takes less than five minutes to perform and adds little cost. He added that treating just seven patients will prevent one case of post-operative AFib.
"It's a quick and easy intervention," he said, noting that surgeons could begin adopting the technique immediately in appropriate patients.
Guideline discourages routine anticoagulation for post-operative AFib
Perhaps the guideline's most nuanced recommendation addresses anticoagulation. Although stroke prevention remains central to managing chronic AFib, Chatterjee said the evidence supporting routine anticoagulation in these patients is surprisingly weak.
Instead of recommending anticoagulation for every patient who develops AFib after cardiac surgery, the guideline issues a Class IIb recommendation encouraging clinicians to individualize treatment based on overall stroke risk and other indications for anticoagulation.
Patients who develop post-operative AFib often are older and have more medical comorbidities, factors that independently increase stroke risk. However, Chatterjee said current evidence does not clearly demonstrate that routine anticoagulation improves outcomes in this specific population.
"We're not saying nobody should be anticoagulated," he explained. "We are saying that you need to be really thoughtful and really deliberate. What we want to discourage is just a reflexive response toward routine anticoagulation."
AFib is a multifactorial complication in cardiac surgery
Chatterjee said post-operative AFib results from multiple contributing factors. More complex procedures, including valve surgery and combined valve-coronary artery bypass operations, carry higher risk than isolated coronary artery bypass grafting. Longer operations, manipulation of the heart, cardiopulmonary bypass, peri-operative fluid management and atrial stretching all appear to contribute.
Because the condition is so common, yet typically transient, Chatterjee said routine electrophysiology consultation is generally unnecessary. A cardiology consultation may be appropriate for patients with persistent arrhythmias.
This updated STS guideline provides surgeons with evidence-based recommendations that emphasize prevention first, practical intraoperative strategies and more selective use of anticoagulation to improve outcomes after cardiac surgery.
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Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: [email protected]