Coronary artery perforation is a rare but serious complication of percutaneous coronary interventions. Aim of this study--to assess inhospital and long term outcomes in patients in whom perforation occurred during coronary intervention and elucidation of predictors of coronary artery perforation. Between May 1997 and October 2002 perforations were formed in the course of percutaneous interventions in 127 patients what amounted 1.08% of 11,793 patients, subjected to coronary interventions, and 0.77% of 16,494 treated coronary segments. Causes of perforations were complex stenoses, chronic occlusions, calcified lesions, small predicted and minimal vessel lumen, high percent stenosis, use of excimer laser or thromboextrator. Rates of arterial perforations and subsequent adverse events including cardiac tamponade and urgent coronary artery bypass surgery as well as mortality had been declining throughout observation period.