How should future angiographic trials be designed?

Summary

As compared to ischemic events-based studies, angiographic trials have the advantage that the effect of therapeutic interventions can be assessed in relatively short periods of time in patient populations of modest size. They also provide insight into the mechanisms of action of mechanical (e.g. PTCA and stent implantations) and other (e.g. pharmacological) interventions. On the other hand angiographic studies cannot replace events-based studies; both approaches should be considered mutually supplementary.

Angiographic trails have been used extensively to determine the efficacy of lipid lowering therapy, particularly of HMG Co-A reductase inhibitors. In spite of differences in patient selection and methods used (including angiographic endpoints) the main results of these studies are remarkably similar, that is, progression of coronary atherosclerosis is significantly reduced but not completely abolished by lipid lowering. Studies which included a large number of patients like REGRESS (n=884) have provided a wealth of useful additional data such as the significance of genetic factors in the atherosclerotic process.

We anticipate that angiographic trails will continue to play an essential role in the study of coronary artery disease, in particular in the evaluation of mechanical revascularization procedures and in studies assessing the effect of pharmacological anti-atherosclerotic treatment. In future there will probably be a growing need for more extensive angiographic evaluations including studies of endothelial function and coronary perfusion.