The clinical features and outcomes of patients with cholesterol embolization syndrome after cardiac catheterization were evaluated. Among 4,920 patients undergoing cardiac catheterization during 1991 to 1996, the symptoms, signs, laboratory data, treatment and prognosis of eight (6 males and 2 females, mean age 69 years old) were reviewed who were pathologically or clinically diagnosed as having cholesterol embolization syndrome. All patients had more than two coronary risk factors. Mobile plaque of the aortic arch was detected in all five patients who underwent transesophageal echocardiography. All patients had one or more precipitating factors, including coronary angiography, percutaneous transluminal coronary angioplasty, cardiovascular surgery and cardiopulmonary resuscitation. The first symptom was renal dysfunction in four patients, skin findings of purple toes in two, muscle pain in one and new onset of refractory hypertension in one. The time after the precipitating factor to the onset of symptoms was 32 +/- 9 days on average. Eosinophilia was found in all patients and six patients revealed eosinophilia before the onset of symptoms. Four patients showed skin findings of purple toes which progressed in three of the four patients even after anticoagulant therapy was discontinued. Epidural anesthesia was markedly effective for skin findings of purple toes in two of the three patients. Diagnosis of cholesterol embolization syndrome is difficult because patients show various symptoms and there is an interval between the precipitating factor and the onset of symptoms. However, the conditions of the patients deteriorate rapidly and the prognosis is generally poor without supportive therapy in the early stage. Our study demonstrated that eosinophilia might be an important clue to early detection of cholesterol embolization syndrome. Furthermore, epidural anesthesia is effective for skin findings of purple toes in patients with cholesterol embolization syndrome. In conclusion, cholesterol embolization syndrome should be detected in the early stage based on eosinophilia or clinical symptoms after cardiac catheterization, and supportive therapy started as soon as possible, including discontinuance of anticoagulant therapy, hemodialysis for renal dysfunction and epidural anesthesia for skin findings of purple toes.