Accidental Cannulation of the Cardiac Venous System During Pericardiocentesis.

A 52-year-old woman presented to another hospital with progressive dyspnea of 10-day duration. The patient was diagnosed with a massive pericardial effusion and underwent pericardiocentesis. However, the patient's symptoms did not improve and she was referred to our hospital with a pericardial sheath in situ. On evaluation, the patient had a large pericardial effusion and evidence of cardiac tamponade, but no fluid could be aspirated from the sheath. This case underscores the importance of image-guided pericardiocentesis.