My understanding is that the more dangerous LDL is the 'small' and the 'very small'. Perhaps I am mistaken.

The angiogram I had did not require a CT scan, but I was on a table with a flouroscope that allowed the gentleman surgeon inserting the catheter into my wrist to see where the detector was located as he manipulated it around the various blood vessel ostia inside my heart. And yes, they inject dye each time they insert the probe into the blood vessel to see if the flow pinches anywhere. If there's a narrowing, there is plaque.

On the other hand, prior to being referred to an electrophysiologist for a catheter ablation (for atrial fibrillation), my cardiologist had me do two MIBI stress tests with contrasting dye. Each one was the equivalent of 500 chest x-rays. What're ya gonna do? They need to check for ischemia, since fixing a fibrillating heart is back asswards when it has severe stenoses. They didn't find any narrowing. even during the angiogram....but I'm still told to take a statin. No ischemia, even at 70, and male, ex officer in the armed forces (stress), but I have to take a stain for life. 🙁

Your CAC is merely and indication of your recent blood chemistry. It's like feeling a garden hose for cool to tell if the water is running inside it and not hot from the sun. In my mind, the gold standard is an angiography....or a 'look-see'.