Pericardial effusion after cardiac surgery: risk factors, patient profiles, and contemporary management.

BACKGROUND: We aimed to review recent experience at our institution in the diagnosis and treatment of pericardial effusion after cardiac surgery and to identify risk factors for its development.

METHODS: We searched our clinical database for patients 18 years or older who had cardiac surgery with cardiopulmonary bypass from 1993 through 2005. For patients with pericardial effusion (study group), medical records were reviewed to evaluate its manifestations and management. To identify risk factors for effusion, study patients were compared with patients without effusions. A second analysis compared the study group with a cohort without effusions who had routine postoperative echocardiographic examination.

RESULTS: Of 21,416 patients identified, 327 (1.5%) had pericardial effusion (study group), 280 (86%) of whom had nonspecific symptoms. Clinical features of tamponade were documented in 138 patients (42%). Effusions were evacuated by echocardiography-guided pericardiocentesis (n = 169, 52%) or surgical drainage (n = 75, 23%). Effusion resolved after left thoracocentesis for pleural effusion in 3 patients (1%); 67 patients (20%) were treated conservatively. In 13 cases (4%), recurrent effusion required drainage after initial pericardiocentesis. Independent risk factors for effusion were larger body surface area, pulmonary thromboembolism, hypertension, immunosuppression, renal failure, urgency of operation, cardiac operation other than coronary artery bypass grafting, and prolonged cardiopulmonary bypass. Previous cardiac operations were associated with lower risk of effusion.

CONCLUSIONS: In our study, pericardial effusion occurred in 1.5% of patients, and symptoms were nonspecific. Several factors, mainly related to preoperative characteristics and type of operation, predispose patients to effusion. Echocardiography-guided pericardiocentesis is effective and safe in these patients.