Objectives: To determine the efficacy of low rate fluoroscopy at 7.5 frames per second (FPS) vs. conventional 15 FPS for reduction of operator and patient radiation dose during diagnostic coronary angiography and percutaneous coronary intervention via the transradial approach.

Background: Transradial approach for cardiac catheterization is potentially associated with increased radiation exposure. Low rate fluoroscopy has potential to reduce radiation exposure.

Methods: Patients undergoing transradial approach diagnostic angiography ± ad hoc PCI, wil be randomized to fluoroscopy at 7.5 FPS vs. 15 FPS prior to procedure. Both 7.5 and 15 FPS fluoroscopy protocols will be configured with a fixed dose per pulse of 40 nGy. Primary endpoints will be operator radiation dose (measured with dosimeter attached to the left side of thyroid shield in µSv), patient radiation dose (expressed as dose-area product in μGy.m2), and fluoroscopy time.

Inclusion Criteria:

• Patients undergoing elective, urgent or emergent cardiac catheterization procedures with or without ad hoc PCI, via transradial approach are eligible.

Exclusion Criteria:

• 1) non-transradial access and 2) participation in research project(s) requiring higher ie 30 FPS cine angiography.