Abrupt closure of coronary artery during coronary intervention is one of major limitations especially in high-risk patients. Platelets are responsible for composing acute thrombotic occlusion at the site of therapeutic arterial injury. Abciximab (platelet glycoprotein IIb/IIIa receptor blocker) might be helpful in preventing the acute thrombotic occlusion. We experienced an excellent effects of the drug in two cases of high-risk patients, unsuccessful thrombolytics and PTCA with acute occlusion. With additional use of abciximab we overcame the complications and succeeded in getting normal coronary flow and resultant successful angioplasties.