ANGIOGRAPHIC EVIDENCE FOR THE ROLE OF TRIGLYCERIDE-RICH LIPOPROTEINS IN PROGRESSION OF CORONARY-ARTERY DISEASE

Recent developments in angiographic technology have enabled quantitati ve assessment of the effects of treatment on coronary arterial lesions . A meta-analysis of 12 angiographic studies showed that treatment to reduce low density lipoprotein (LDL) cholesterol levels decreases angi ographic progression of coronary artery disease (CAD) by one-third, an d increases the chance of lesion regression two-fold. However, these s tudies also show that the response to treatment to LDL cholesterol lev els varies according to the severity of the coronary artery stenosis; lesions were seen to regress with treatment only if there was >50% cor onary artery stenosis at baseline. Other variables that have been impl icated in CAD progression include intermediate density lipoproteins (I DL), non-high density lipoproteins (non-HDL) cholesterol and very low density lipoproteins (VLDL). Levels of IDL have been shown to decrease to a greater extent in patients whose lesions did not progress than i n patients showing lesion progression. In untreated patients? an incre ase in non-HDL cholesterol was associated with an increase in risk of disease progression. In contrast, the most important predictor in trea ted patients was apo CIII (a marker of triglyceride-rich lipoprotein m etabolism). Possible mechanistic links between triglyceride levels and CAD progression are discussed.