title: The role of anticoagulation in the development of pericardial effusion and late tamponade after cardiac surgery.
abstract: This study aimed at elucidating the role of anticoagulation in the genesis of late pericardial effusion and tamponade after cardiac surgery. Using serial 2-D echocardiography, 141 patients undergoing surgery for coronary artery bypass (56), valvular (69) or congenital (16) [corrected] heart disease were studied postoperatively. Group 1 (74 patients) received full anticoagulation (warfarin 73; heparin 1) and group 2 (67 patients) received either antithrombotic agents (aspirin plus dipyridamole), or no treatment. Fifty percent (70/141) of patients developed effusion. There was no significant difference between the two groups in the incidence of either effusion in general (43/74; 58% vs 27/67; 40%, respectively) or small or medium sized effusion. However, a large effusion was significantly more common in group 1 than in group 2 (32% vs 4%, P < 0.005). Twelve patients (12/141; 8.5%) developed late tamponade, 7 to 33 (15 +/- 7.3 mean +/- SD) days after surgery. All had a large effusion demonstrated by echo, drained by pericardiocentesis, and none died. All 12 patients with tamponade belonged to group 1 (P < 0.001). Excess anticoagulation was detected at least once in 41 of the 74 group 1 patients (55%). When compared to properly anticoagulated patients, excessively anticoagulated patients had a similar overall incidence of effusion and a similar incidence of small or moderate effusion, but a higher incidence of large effusion (18% vs 44%, [corrected] P < 0.05) and tamponade (3% vs 27%, P < 0.025). We conclude that, unlike small or medium-sized effusions, large pericardial effusions and tamponade are more likely to occur among anticoagulated patients, especially if they are excessively anticoagulated.
authors.affiliation: Division of Cardiology, American University of Beirut Medical Center, Lebanon.
authors.forename: J F
authors.initials: JF
authors.lastname: Malouf
authors.forename: S
authors.initials: S
authors.lastname: Alam
authors.forename: W
authors.initials: W
authors.lastname: Gharzeddine
authors.forename: M A
authors.initials: MA
authors.lastname: Stefadouros
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D001241:Aspirin / Q000008:administration & dosage / Q000627:therapeutic use; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002305:Cardiac Tamponade / Q000139:chemically induced* / Q000209:etiology; D001026:Coronary Artery Bypass; D004176:Dipyridamole / Q000008:administration & dosage / Q000627:therapeutic use; D004452:Echocardiography; D005260:Female; D006330:Heart Defects, Congenital / Q000601:surgery; D006351:Heart Valves / Q000601:surgery; D006493:Heparin / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D008297:Male; D010490:Pericardial Effusion / Q000139:chemically induced* / Q000209:etiology; D011183:Postoperative Complications; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin; D004176:Dipyridamole; D006493:Heparin; D001241:Aspirin