Late cardiac tamponade following open-heart surgery. Diagnosis and treatment.

Late cardiac tamponade is a rare but serious complication following open-heart surgery. It occurred in 9 (0.8%) of 1 094 consecutive patients 6 to 13 (median 8) days after operation. Six patients had undergone valve replacement and three coronary bypass surgery. All were on anticoagulant medication postoperatively (median TT index 7%). Early symptoms of cardiac tamponade were nausea and general malaise (present in all 9 cases), whereas classical signs of tamponade such as arterial hypotension and distended neck veins appeared late. The cardiac silhouette was radiographically enlarged in all cases, but this finding was seldom diagnostic. Computed tomography gave the surest diagnosis and permitted quantitative assessment of the fluid in the pericardium. Pericardial needle puncture was effective in temporarily relieving the tamponade, but insertion of a tube by the subxiphoid approach gave definitive drainage.