Previous studies have shown that the transradial cardiac catheterization has decreased not only bleeding complications related to the access site and procedural discomfort but also morbidity and hospitalization as compared to transfemoral approach. At present, the right radial approach (RRA) is the first choice routinely for coronary angiography and interventions in daily clinical practice despite more marked subclavian artery tortuosity than left radial approach (LRA). Although LRA has been thought to be more direct access to the ascending aorta similar to transfemoral approach and may reduce fluoroscopy time and cerebrovascular complications compared with RRA, the application of LRA for coronary intervention is still low. Moreover, several studies have also obtained conflicting results showing no difference in procedural success rate compared LRA and RRA using Judkins catheters. To date, it remains unclear whether LRA is superior to RRA in term of safety and feasibility for coronary angiography and interventions in real world practice and few data of randomized control trial are available.

The aim of this study was to randomly investigate and compare the safety and feasibility of LRA compared with RRA for coronary diagnostic angiography in Chinese subjects.

The investigators will enroll consecutively for 2 years all patients undergoing coronary diagnostic procedures through trans radial approach.

The primary outcome was total procedural duration. Secondary outcomes included fluoroscopy time, dose of radiation including cumulative air kerma and dose area product, contrast volume and the incidence of vascular complications.

Inclusion Criteria:

• All consecutive patients who undergo to diagnostic coronary procedures

Exclusion Criteria:

• Acute ST-elevation myocardial infarction
• Previous coronary artery bypass graft surgery
• Hemodynamic instability