CCTA after 1,000+ CAC score - warranted?

I would not hesitate to get the angiogram. I've done it. The more you know, the better.

The meds are to (1) keep LDL cholesterol low so that the problem doesn't get worse, and (2) thin the blood to prevent dangerous blood clots from soft plaque.

I can relate to your situation. After my normal cardio appt in 2018 he suggested that I have my CAC tested (that day). It came back at 1015 (age 61). He called me that same afternoon and scared the hell out of me. He told me that I had a 20-25% chance of a major cardiac event per year and ordered a stress test for the next day, which I passed. I changed cardiologist because he was so fatalistic.

Due to bad genes I have been on various statins for over 30 years (father died at 55 following second open heart when I was 15) and have always controlled my cholesterol levels (which started at 376!) I also take 10 mg of zetia with my 20mg of rosuvastatin.

My new cardiologist recommended a second CAC scoring in Nov. 2022 (CTA with contrast). Like you, the vast majority of my calcium is in LAD and RM. Surprisingly I only had a CAC of 1185, much lower progression than I expected. However, since there was stenosis over 50% he had ordered that an FFR (fractional flow analysis). This calculates a value that measures blood flow rather than just degree of blockage. Most indicate that if this falls below 0.80 that you should be stented, although I have seen references that state 0.75. Part of my LAD was down to 0.76, but the cardio said it wasn't stentable.

Even with all of these test results I am still asymptomatic at 68. So many on these threads panic and go in search of some magic bullet to reduce calcium and go on crazy diets or spend tons of money on a variety of dubious supplements. I eat/drink what I want (I like my red meat and carbs) and have never taken any supplement except for vitamin D2 since I had a deficiency.

Once you have a high CAC like us there is not much you can do to change your fate. I am all for enjoying life and think that a positive attitude is more important than any other factors. Easier said than done!

He has had to heart cath and dye with stress test and goes for an echo today and goes back Friday for the report to see what’s next!!

Cardiac cath is improved and less
risky than years past.
Another important test is carotid ultrasound. Watching CRP and the
Mediterranean diet helps as well.
Statins and CoQ10 are anti inflammatory. Alcohol is not good for our heart health . I try to walk every day.

I haven't looked to see what Zeria is, but the statin is buying you time. It doesn't prevent all further deposition of plaque, but it does/should slow it down some...more if you take more.

At some point, a scan is likely to show that you're plaque is closing off the flow of blood, and that is when you will need a stent/bypass...whatever it turns out to be, but you should hope that you don't experience angina beforehand. Angina is a distinct sign of 'ischemia', meaning low oxygenation of, in this case, heart muscle.
I had an angiogram. It's no big deal. The two worst parts were the chilly, actually cold, cath lab (I was vibrating when I was invited to lift myself onto the wheel chair, but the orderly wrapped me in a warmed blanket...BLISS!), and then having to lie flat for three hours with a heavy compress on my wrist for safety to prevent the vein from opening again.

Thanks for all the replies and advice. Agree it is best to keep a positive attitude as anyone could get hit by a bus tomorrow and then no need to worry about cholesterol or calcium plaque. Still, the point of the exercise in finding out your CAC score is not just knowing it, but taking the next step to know if and where there is any narrowing especially in that LAD or RCA. Has anyone had the CT test with contrast dye to get a much closer look at these arteries and note any narrowings? Were they accurate? I’ve seen research that says a CAC score more than 1000 is just a warning and the plaque could all be solid and no obstructions or narrowing so without actually looking at those specified arteries it means little in the way of stroke heart attack risk if you are asymptomatic (no)?

What about an angiogram? That is how they can really see what the story is. That's what you want to find out.

I have had two MIBI tests, on treadmill, with CT and contrast. Their information pamphlet said it's the equivalent of 500 chest x-rays. Not sure you should be so keen to get one of those unless it is clearly indicated and that other tests have failed to pinpoint a cause of your ischemia or arrhythmia.
https://x-ray.ca/services/cardiac-heart-health/mibi/

I was able to get my LDL down by taking Repatha medication twice monthly The number is now 14! This should lessen the load on my arteries, moving forward, and hopefully extending my life I could not tolerate statins because of the pain in the muscles and joints.

Fortunately, I can take statins with no problem (taking as much as 80mg of one). I hover around LDL of 50 at 20mg, tried 40 mg for a while and got down to the 30's, but doc thought that low wasn't necessary. Glad the Repatha works for you, it seems to really benefit most people.