As explained in this study, here’s another trick for reducing both the patient radiation dose and the patient iodine dose in cardiac CTA: lower the kVp to 100 or 80 or even lower.
Of course, you can accomplish this same outcome by using dual energy CT and viewing the vessels with lower keV or kVp while viewing everything else at higher energies.
The following passage, from an article on HealthImaging.com, caught my attention:
The honeymoon has ended for coronary CT angiography (CCTA) and the seven-year itch has commenced for some radiologists and cardiologists. They do not advocate replacing the technique though. Rather, they are asking if the requirements in training guidelines need a makeover to reduce variability and better maximize CCTA’s potential to improve patients’ clinical care and outcomes.
This brings up a good point: the credentialing criteria for performing and interpreting cardiac CT are now too low. I found the learning curve was long with a gradual slope. You need to be in a training and supervised environment with a fairly good case load for at least a year. It’s challenging, but performed well and interpreted with skill, it is a very valuable test which can save the healthcare system considerable cost – especially in low- to moderate-risk chest pain patients presenting to an emergency room.