Percutaneous pericardiocentesis guided by two-dimensional echocardiography was introduced in 1983 as an alternative to electrocardiographically or fluoroscopically guided puncture for the management of pericardial effusion. The objective of this study was to investigate echocardiographically (echo) - guided pericardiocenteses performed at Yonsei Cardiovascular Center from January 1, 1993 to December 31, 2003, and also to determine whether patient profiles, etiology, and practice patterns have changed over this 11-year period. The medical records of 272 patients were examined and a follow-up survey was conducted. Patient clinical profiles, etiology, echocardiographic findings, and procedural details were determined for 2 periods: January, 1993 through December, 1997 (period 1) ; and January 1998 through December, 2003 (period 2). During the 11-year study period, 291 therapeutic, echo-guided pericardiocenteses with pericardial catheter drainage were performed in 272 patients. The number of pericardiocentesis in period 2 was increased compared with period 1 (191 cases vs. 100 cases). The mean age at pericardiocentesis increased from 49 ±17 years in period 1 to 55±16 years in period 2 (p < 0.05). The procedural success rate was 99% overall with a major complication rate of 0.7% (2 cases of right ventricular free wall perforation which required emergency operation). Only one procedure-related mortality (< 30 days) was noted. Malignancy was the leading cause of a pericardial effusion requiring pericardiocentesis (45.6%). The incidence of pericardial effusion following cardiothoracic surgery and percutaneous coronary intervention procedures accounted for nearly 20% of all pericardiocenteses performed.