What is coronary atherosclerosis?

Plaque buildup: Little spots along the coronary arteries (they "crown" the heart) develop patches of macrophages that become loaded with cholesterol, and eventually scarring narrows the artery; the spot may burst or a bleed into the spot, either causing sudden death. There are many fewer deaths from coronary atherosclerosis today than in the past, mostly due to healthier lifestyles.

Artery disease+Clots: Artery disease, aka atherosclerosis, is an accumulation of white blood cells, mostly macrophages which have invaded into the walls of arteries to remove low density lipoprotein (fat carrying protein) particles. The macrophages may die if overwhelmed with fat molecules & cannot export the ingested fat into high density lipoprotein particles. Ruptures of plaque induces clots which narrow the artery.