A simple surgical technique during cardiac surgery was associated with a 56% reduction in the incidence of atrial fibrillation, which can lead to stroke, with no added risks or side effects, according to a study by Weill Cornell Medicine and NewYork-Presbyterian investigators.
The findings suggest that the method, called posterior left pericardiotomy, has significant potential for preventing prolonged hospital stays and the need for additional interventions and drugs to reduce the risk of strokes and heart failure associated with atrial fibrillation.
The study evaluated whether a posterior left pericardiotomy, a slit in the back-side of the sac around the heart to drain excess fluid, could help prevent atrial fibrillation in patients after cardiac surgeries. The randomised controlled trial was published in The Lancet, and the study investigators also presented the findings on 14 November as part of the American Heart Association’s Scientific Sessions 2021.
“Previous studies were small, with major limitations in study design, so there was no clear direction on whether posterior left pericardiotomy is beneficial for preventing atrial fibrillation,” said lead investigator Dr Mario Gaudino, the Stephen and Suzanne Weiss professor in Cardiothoracic Surgery at Weill Cornell Medicine and a cardiothoracic surgeon at NewYork-Presbyterian/Weill Cornell Medical Center.
“Our study is the first to provide rigorous evidence of the benefits of the technique in a large group of patients at a single institution.”
A build-up of excess fluid and small clots is common after cardiac surgery, occurring in about two-thirds of patients. Even a small build-up can trigger the development of atrial fibrillation, a complication in which irregular electrical signals prevent the heart’s upper chambers from contracting effectively. Atrial fibrillation is the most frequent adverse event after heart surgery, reported in about 35% of patients.
Treatment may involve an electrical shock to restore a regular heart rhythm, followed by taking drugs for controlling heart rhythm and lowering the risk of blood clots, which all have side effects and complications.
To perform a posterior left pericardiotomy, the surgeon makes an incision in the back-side of the sac around the heart, called the pericardium. This allows excess fluid and small clots from the pericardium to drain into the space around the left lung, called the left pleural cavity. The procedure adds just a few minutes to the overall cardiac surgery time. A left pleural drainage tube is inserted and generally removed few days after surgery as part of standard care. Excess fluid continues to drain through the slit in the pericardium until it heals on its own.
For their study, the investigators randomly assigned 420 patients undergoing elective surgery to coronary arteries, the aortic valve or ascending aorta to two groups: 212 patients received a posterior left pericardiotomy during their surgeries and 208 patients did not receive the additional surgical procedure.
Atrial fibrillation developed in 37 of 212 patients (18%) in the pericardiotomy group, significantly lower than 66 of 208 patients (32%) in the no-pericardiotomy group. Importantly, no complications were associated with pericardiotomies.
The study was funded entirely by the Department of Cardiothoracic Surgery at Weill Cornell Medicine, made possible through philanthropy from patients and fundraising efforts. “This study demonstrates our commitment to conducting rigorous clinical research and answering important questions that are meaningful to patients,” said Gaudino, who is also director of the Joint Clinical Trials Office at Weill Cornell Medicine and NewYork-Presbyterian.
He and a team of investigators from the Department of Cardiothoracic Surgery at Weill Cornell Medicine are now working with international colleagues to design a multicentre clinical trial that will include more patients and types of heart surgeries, such as mitral valve repair.
“We are excited that our proof-of-concept clinical trial has demonstrated the benefits of posterior left pericardiotomy, with no additional risks to patients,” said senior author Dr Leonard Girardi, chairman of the Department of Cardiothoracic Surgery and the O. Wayne Isom professor of Cardiothoracic Surgery at Weill Cornell Medicine, and cardiothoracic surgeon-in-chief at NewYork-Presbyterian/Weill Cornell Medical Center.
“We look forward to confirming our results in a multicentre study in the future and hope this technique may one day become the standard of care for heart surgery patients across the globe.”
Study details
Posterior left pericardiotomy for the prevention of atrial fibrillation after cardiac surgery: an adaptive, single-centre, single-blind, randomised, controlled trial
Mario Gaudino, Tommaso Sanna, Karla V Ballman, N Bryce Robinson, Irbaz Hameed, Katia Audisio, Mohamed Rahouma, Antonino Di Franco, Giovanni J Soletti, Christopher Lau, Lisa Q Rong, Massimo Massetti, Marc Gillinov, Niv Ad, Pierre Voisine, J Michael DiMaio, Joanna Chikwe, Stephen E Fremes, Filippo Crea, John D Puskas, Leonard Girardi.
Published in The Lancet on 14 November 2021
Summary
Background
Atrial fibrillation is the most common complication after cardiac surgery and is associated with extended in-hospital stay and increased adverse outcomes, including death and stroke. Pericardial effusion is common after cardiac surgery and can trigger atrial fibrillation. We tested the hypothesis that posterior left pericardiotomy, a surgical manoeuvre that drains the pericardial space into the left pleural cavity, might reduce the incidence of atrial fibrillation after cardiac surgery.
Methods
In this adaptive, randomised, controlled trial, we recruited adult patients (aged ≥18 years) undergoing elective interventions on the coronary arteries, aortic valve, or ascending aorta, or a combination of these, performed by members of the Department of Cardiothoracic Surgery from Weill Cornell Medicine at the New York Presbyterian Hospital in New York. Patients were eligible if they had no history of atrial fibrillation or other arrhythmias or contraindications to the experimental intervention. Eligible patients were randomly assigned (1:1), stratified by CHA2DS2-VASc score and using a mixed-block randomisation approach (block sizes of 4, 6, and 8), to posterior left pericardiotomy or no intervention. Patients and assessors were blinded to treatment assignment. Patients were followed up until 30 days after hospital discharge. The primary outcome was the incidence of atrial fibrillation during postoperative in-hospital stay, which was assessed in the intention-to-treat (ITT) population. Safety was assessed in the as-treated population.
Findings
Between 18 Sept 2017, and 2 Aug 2021, 3,601 patients were screened and 420 were included and randomly assigned to the posterior left pericardiotomy group (n=212) or the no intervention group (n=208; ITT population). The median age was 61·0 years (IQR 53·0–70·0), 102 (24%) patients were female, and 318 (76%) were male, with a median CHA2DS2-VASc score of 2·0 (IQR 1·0–3·0). The two groups were balanced with respect to clinical and surgical characteristics. No patients were lost to follow-up and data completeness was 100%. Three patients in the posterior left pericardiotomy group did not receive the intervention. In the ITT population, the incidence of postoperative atrial fibrillation was significantly lower in the posterior left pericardiotomy group than in the no intervention group (37 [17%] of 212 vs 66 [32%] of 208 [p=0·0007]; odds ratio adjusted for the stratification variable 0·44 [95% CI 0·27–0·70; p=0·0005]). Two (1%) of 209 patients in the posterior left pericardiotomy group and one (<1%) of 211 in the no intervention group died within 30 days after hospital discharge. The incidence of postoperative pericardial effusion was lower in the posterior left pericardiotomy group than in the no intervention group (26 [12%] of 209 vs 45 [21%] of 211; relative risk 0·58 [95% CI 0·37–0·91]). Postoperative major adverse events occurred in six (3%) patients in the posterior left pericardiotomy group and in four (2%) in the no intervention group. No posterior left pericardiotomy related complications were seen.
Interpretation
Posterior left pericardiotomy is highly effective in reducing the incidence of atrial fibrillation after surgery on the coronary arteries, aortic valve, or ascending aorta, or a combination of these without additional risk of postoperative complications.
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