Is high cholesterol considered a cause of heart disease?

Yes: It's a risk factor. Smoking, hypertension, diabetes, age, and family history of premature heart disease are also risk factors.

Cholesterol: High cholesterol is a major risk factor for atherosclerosis.

Inflammation: It is the amount of damage in vessel wall due to inflammation that creates risk - cholesterol is used by body to repair vessels - having good cholesterol is good (works like joint compound for sealing dry wall) - the bad cholesterol like LDL and lipoprotein a creates risk. High cholesterol means your liver and gall bladder is not converting cholesterol to bile need b6 to normalize this.

No, Lipoproteins are: Cholesterol, made by every animal cell, has long been promoted by the NIH as a surrogate marker for Low Density Lipoproteins because of correlation if cholesterol >350 mg/dL, yet ↑ingly unreliable when lower. LDL particles carry 3 to 6,000 fat molecules/particle & are NOT equivalent to cholesterol. Thus focus on NMR lipoprotein concentrations & avoid low fat diet which routinely drives LDL↑ & HDL↓