ECHOCARDIOGRAPHIC EVIDENCE OF PERSISTENT PERICARDIAL-EFFUSION AFTER OPEN-HEART-SURGERY

Cross-sectional and M-mode echocardiography were used to review 33 pat ients 6-28 months (mean 19 months) after open heart surgery. Eleven pa tients had had echocardiographic signs of pericardial effusion during the first week after open heart surgery (Group A), and 22 had not (Gro up B). At review, pericardial effusion was found in 73% of subjects in Group A compared with 18% of those in Group B (P < 0.01). On average, posterior effusions were small (mean dimension in systole 0.9 cm) but they were detected reproducibly (interobserver agreement 97%). Anteri or echo-free spaces (<0.5 cm) were found frequently, but interobserver variation in their detection was high (agreement in 68%). Symptoms di d not correlate with the presence of a late post-operative effusion bu t the groups were not matched for rhythm or ventricular function. Five patients in Group A had developed atrial fibrillation in association with their early post-operative effusion, and four of these had persis ting atrial fibrillation at this review. These results suggest that ec ho-free spaces around the heart, suggestive of small pericardial effus ions, may persist for many months after open heart surgery.