Added this text:
Glycated LDL May Be The CulpritAn intriguing study published in May, 2011 may explain both why measuring cholesterol gives such confusing correlations with heart disease and why the A1c predicts it so much better.
The study is Glycation of LDL by Methylglyoxal Increases Arterial Atherogenicity: A Possible Contributor to Increased Risk of Cardiovascular Disease in Diabetes. Naila Rabbani et al. Diabetes. Published online before print May 26, 2011, doi: 10.2337/db11-0085
You can read a good explanation of what this study means here:
Science Daily: Super-Sticky 'Ultra-Bad' Cholesterol Revealed in People at High Risk of Heart Disease
In brief the finding is this: LDL becomes dangerous when it becomes glycated--i.e. when sugar molecules become bonded to it. When that happens it is more likely to stick to the artery walls. It is very likely given the correlation between heart attack and A1c that LDL becomes dangerously glycated at a rate that corresponds to the rate at which hemoglobin becomes glycosylated--which is what the A1c measures. (Glycosylation is permanent glycation.)
Also deleted suggestion to get a CRP test as recent research suggests it is not a good predictor of the value of statins in people who don't already have significant heart disease.