PericaRdiotomy IN Cardiac surgEry (PRINCE) trial: rationale and design

Postoperative atrial fibrillation affects approximately 30% of cardiac surgery patients and is associated with an increased risk of stroke, mortality, and length of hospital stay. While posterior pericardial effusion is thought to be a key modifiable trigger, definitive evidence regarding the efficacy of posterior left pericardiotomy to prevent postoperative atrial fibrillation and improve long-term outcomes is lacking. The PericaRdiotomy IN Cardiac surgEry (PRINCE) trial is a prospective, multicentre, international, blinded, randomized controlled trial designed to address this knowledge gap. The trial will randomize approximately 1,400 patients without a history of atrial fibrillation undergoing cardiac surgery to receive either posterior left pericardiotomy or no posterior left pericardiotomy. This simple surgical intervention facilitates continuous drainage of pericardial fluid into the left pleural space in the postoperative period. The early co-primary endpoint is the incidence of in-hospital atrial fibrillation within five days of surgery. If the early co-primary endpoint demonstrates efficacy, the trial will proceed to assess the late co-primary endpoint. This long-term endpoint is a hierarchical composite of all-cause death, stroke, systemic embolism, unplanned hospital readmission for cardiac reasons, or atrial fibrillation after 30 days, analyzed using the win ratio over a follow-up of up to five years. By targeting a diverse patient population and employing long-term structured follow-up, the PRINCE trial will definitively evaluate whether concomitant posterior left pericardiotomy during cardiac surgery prevents postoperative atrial fibrillation after cardiac surgery. The trial presents a unique opportunity to establish whether preventing perioperative atrial fibrillation translates into long-term survival and morbidity benefits.