Is nuclear stress test or cardiac cta better for ruling out clogged arteries? my nuclear test was clear but they couldnt do cta due to heart rate.

Nuclear stress test: The nuclear stress test is better because (1) it is a functional test - your heart is actually "stressed" to beat harder, & (2) you can do it at any heart rate (as you've seen). The cardiac CTA only tells you anatomy - whether or not there is calcium in the arteries - not how your heart functions. Not all plaques contain calcium, either, so cardiac CTA has false negatives also. Talk to your doctor