Determinants of pericardial drainage for cardiac tamponade following cardiac surgery

Objective: We aimed to identify independent risk factors predisposing toward postoperative surgical or percutaneous pericardial drainage following cardiac surgery, and to assess late survival. Methods: A retrospective review of preoperative, intra-operative and postoperative variables was conducted in 5818 patients, who underwent adult heart surgery in a 7-year time span (2002-2009). Pericardial drainage was performed in 117 patients (2%), of whom 52 (44%) were evacuated by surgical drainage and 65 (56%) by echocardiographic-guided pericardiocentesis. Patients were divided in two groups: patients with two-dimensional (2D) echocardiographic evidence of cardiac tamponade, who underwent pericardial surgical or percutaneous drainage (group I: 117 patients); and patients without cardiac tamponade (group II: 5701 patients), who served as the control group. Results: The two groups were compared with univariate analysis, and variables significantly (p≤ 0.05) or possibly (p≤ 0.2) associated with pericardial drainage were entered into multivariable logistic regression analysis models assessing the role of pre-, intra- and postoperative variables together or separately. Pericardial drainage was more likely to occur in patients undergoing combined procedures such as double/triple valves or surgery on ascending aorta, in patients with higher EuroSCORE (European System for Cardiac Operative Risk Evaluation) levels, whereas patients receiving aspirin treatment before surgery had a lower risk of this complication. In addition, postoperative blood product transfusion and the occurrence of renal failure after surgery increased the risk of this complication. Conclusions: Postoperative pericardial drainage is an uncommon complication after heart surgery, mainly managed percutaneously. Our study has identified different independent causative factors for cardiac tamponade requiring pericardiocentesis. The identification of preoperative and postoperative risk factors may be useful to adopt strategies to further reduce the incidence of pericardial tamponade requiring drainage.