Evolution of coronary stenoses is related to baseline severity--a prospective quantitative angiographic analysis in patients with moderate coronary disease

A correlation of the angiographic evolution of coronary stenoses(stenosis diameter 20%) with morphological stenosis parametersat baseline could help to identify the risk of progressive stenoses.Therefore, the data of the prospective INTACT study (InternationalNifedipine Trial on Antiatherosclerotic Therapy) were reviewed.In 348 patients with moderate coronary artery disease, standardizedcoronary angiograms were taken 3 years apart and were quantitativelyanalysed. Changes in the minimal diameter of the 1063 preexistingcoronary stenoses compared between both angiograms were setin relation to a number of conventional stenosis parametersat baseline. Regression analysis demonstrated a significantcorrelation of the changes in minimal diameter with baseline% diameter stenosis (r=0.30; P<0.001), minimal diameter (r=—0.28;P<0.001) and reference diameter of stenoses (r=–0.14;P<0.001). The changes were not correlated with stenosis lengthand plaque area. The baseline parameters of 22 preexisting stenosesprogressing to occlusions differed from those remaining patentonly with regard to the % diameter stenosis (43 ± 9%vs 39 ± 11%; P<0.05). Additional progression of coronarydisease became manifest through development of 228 stenosesand 19 occlusions at arterial sites free from definitive stenosesin the baseline angiograms. Thus, progression of atherosclerosis predominantly occurredin mild preexisting coronary stenoses and developed at previouslyangiographically normal sites. Since the conventional angiographicparameters analysed in this study failed to identify individualarterial sites with an increased risk for progression, definitionof new angiographic parameters or application of new techniquesseem mandatory to this end.