BACKGROUND AND OBJECTIVES: The safety and efficacy of outpatient cardiac catheterization was established. We evaluated our patient population and complications selected for outpatient procedures and our experience with transradial approach. MATERIALS AND METHODS: A total of 346 outpatient cardiac catheterization (31% of all diagnosticprocedures),performed with transradial approach, was compared with 788 in patient diagnostic procedures in terms of patient population, clinical and angiographic features, complications of examinations. RESULTS: 1) Indications of outpatient coronary angiography were as follows: follow-up of coronary interventions or bypass surgery (41.6%), recent-onset or aggravated angina (31.2%), atypical chest pain (19.4%), stable angina (3.8%), recent myocardial infarction (2.9%), variant angina (0.9%), preoperative evaluation of valvular or congenital heart disease (0.3%). 2) Significant coronary lesions were found in 216 (62.5%) patients and left main disease in 1 2 (3.5%). Coronary spasm test, internal mammary artery or saphenous vein graft angiography, aorto-ileofemoral angiography, and bilateral carotid angiography were safely performed as indicated. 3) Success rate of examination by primary approach was 94.5%, similar to 94.9% of inpatients. Alternative brachial or femoral approaches were needed in 19 (5.5%) patients. 4) No death, cerebral thromboembolism or myocardial infarction were observed and one-day admission was required in 13 (3.7%) patients. Initial 254 patients (33%) showed good radial pulse (94%), weak or absent radial pulse (6%), abnormal reverse Allen test (6%) up to 61+/-25 days. However, no claudication was observed. CONCLUSION: Cardiac catheterization and angiography was safely performed in the outpatient population selected using much extended inclusion criteria. Transradial approach is useful to set up outpatient procedures with less facilities and personnels and makes it available in the daytime with low readmission rate.