First I send your sister good wishes for a speedy recovery and that you also can remain calm through this shock of unexpected news.

Dr. Malcolm Kendrick has put his thirty years of thinking about what causes heart disease to work just last week, writing a series on "so what does cause heart disease?" Only three parts up so far, but the story is...many different and seemingly unrelated immediate causes. (But not cholesterol) It needs an approach from another angle. http://drmalcolmkendrick.org

As I remember his book "The Great Cholesterol Con" he wound up where many doctors were before the lipid hypothesis..with stress. But stress of the societal or psychological kind, the displaced peoples of Finland being an example. While Keys would point to high fat consumption in the country, Finland had absorbed large numbers of other non-Finn ethnic groups; who could not get jobs, no way to support their families, no one could speak the language, they were outsiders, struggling to find a place in society.