There is so much reductionist science that is funded by one lobby group or another that you'll get lost pretty quickly.
Just remember this: The foundation that most of these studies are based on is the lipid hypothesis:
http://en.wikipedia.org/wiki/Lipid_hypothesis
You
should take particular note of the second word. Hypothesis is just that. It has never been proven, and is again a reductionist view that looks at a symptom and assumes that it's the
root cause.
Lipids are fats. Fat is grease. What do we use grease for in machines? We use grease for two things. Lubrication and protection from oxidation.
Why do we need lubrication in mechanical things? Because parts are so tightly coupled together that they rub on each other when they move, causing friction. What is a biological analogy for this situation? Inflammation.
So we now have two biological situations where increased blood lipids are a natural and reasonable response by the body to protect itself.
Now lets look at the underlying starting points: oxidative stress and inflammation. In a biological system, these typically go hand in hand.
I could go on and on more than I already have... My point is that heart disease is a manifestation of a complex situation that probably starts when the body is lacking the necessary inputs to counter oxidative stress and facilitate smooth operations.
This will include a properly functioning digestive system, balanced and sufficient nutritional intake, introducing stress in ways that the body is designed to cope with and is necessary for optimal functioning (like exercise), reducing stress in ways that the body is not designed to cope with (like environmental pollutants), allowing your body time to relax and detox, and resolving emotional stresses due to inter-personal relationships, etc.
All chronic conditions in the body are manifestations of complex interrelated systems working out of harmony with each other. Heart disease is no different.