Angiography and IVUS from Left Radial Access

I routinely administer 4-5,000 U heparin into the radial sheath immediately after getting access. In one of Dr. Rao's videos, it is recommended to delay this until aortic root access is obtained in case of radial loops, etc. How early after sheath placement would radial occlusion occur? And so, does it matter if heparin is administered immediately after sheath placement vs. waiting until the root is reached, or even waiting until the coronaries are imaged?

I typically use right radial access even when patients have LIMA grafts, because I believe that my radiation exposure (as opposed to total fluoroscopy time) is increased by using left radial access and leaning across the patient (I am 5'7" tall). I only use the left side when I must, as I find standing on the patient’s left side with the monitor at his or her feet to be more awkward. What are your favorite catheters for left subclavian access via the right radial?