Is atherosclerosis the main cause of cardiovascular disease.?

Yes. In fact chd accounts for more than 1/3 of all deaths in pts greater than 35 years of age.
Yes and no. Atherosclerosis is a disease of the western world where we eat poorly and do not exercise enough. In developing countries, infectious disease illnesses are much more prominent. I remember discussing this with dr. Augustin castellanos of venezuela. He indicated that coronary artery disease was unusual in venezuela and chaga's disease is much more of a problem.

Related Questions

Why does atherosclerosis run in families? Is it just a gene that runs through and you just naturally develop cardiovascular disease or is it because of the risk factors that run in families?

Risk factors. The more risk factors one has, the more likely they are to develop atherosclerotic vascular disease, whether that is in coronary arteries or other arteries in the body. Family history is certainly a strong risk factor, but others include high blood pressure, high cholesterol (can also be hereditary), smoking and diabetes.
Combination. Genetic and behaviors that are common to some families. Smoking overweight sedentary hypertension hypercholesterolemic hypothyroid etc.
Genetics. High cholesterol, high blod pressure and other risks factors are genetically determined and may be responsible for early onsetnheart disease. That said, may risk factors such as obesity or smoking can be modified and lower your overall risk.