The effect of subcutaneous glyceryl trinitrate on radial artery diameter and the utility in radial access coronary angiography

A transradial arterial approach is being used more frequently for coronary angiography due to the lower vascular complications and lower bleeding rates reported in recent large trials. Radial artery spasm, subclavian tortuosity and the increased technical difficulty of puncturing a smaller and more mobile artery are causes for access failure. This prospective randomised placebo controlled trial aims to look at the role of subcutaneous glyceryl trinitrate, as a vasodilatory agent, injected prior to arterial puncture to improve the technique. Radial artery diameter change will be assessed using ultrasound at the site of injection as well as the contralateral side to review for a systemic effect. Time to successful arterial access will be recorded and patient satisfaction in the form of pain scores will also be recorded.