Everything I've ever read says fatty deposits. The NHS website calls fatty deposits "atheroma". You can find multiple definitions of atherosclerosis/atheroma in other places describing them the same way. Wikipedia says:
"While the early stages, based on gross appearance, have traditionally been termed fatty streaks by pathologists, they are not composed of fat cells but of accumulations of white blood cells, especially macrophages, that have taken up oxidized low-density lipoprotein (LDL)."
So whilst it may be more accurate to say they are white blood cells that fed on LDL (and presumably contain fatty substances as a result) there is a long tradition of calling them fatty substances, and there is at minimum a connection to fat.
It seems misleading to try to discount the role of the fat to me. They don't sound like they are just normal white blood cells. Is there any doubt that the fat plays a causative role? I know a couple of cardiologists who say it is clear. Do you have some references for the idea that fat is not relevant?
"While the early stages, based on gross appearance, have traditionally been termed fatty streaks by pathologists, they are not composed of fat cells but of accumulations of white blood cells, especially macrophages, that have taken up oxidized low-density lipoprotein (LDL)."
So whilst it may be more accurate to say they are white blood cells that fed on LDL (and presumably contain fatty substances as a result) there is a long tradition of calling them fatty substances, and there is at minimum a connection to fat.
It seems misleading to try to discount the role of the fat to me. They don't sound like they are just normal white blood cells. Is there any doubt that the fat plays a causative role? I know a couple of cardiologists who say it is clear. Do you have some references for the idea that fat is not relevant?