IMPAIRED COMPENSATORY CORONARY-ARTERY ENLARGEMENT IN ATHEROSCLEROSIS CONTRIBUTES TO THE DEVELOPMENT OF CORONARY-ARTERY STENOSIS IN DIABETIC-PATIENTS - AN IN-VIVO INTRAVASCULAR ULTRASOUND STUDY

Aims Coronary arteries affected by atherosclerosis undergo focal compe nsatory enlargement, which can be detected by intracoronary ultrasound but not by angiography. Diabetic patients when compared with non-diab etics have a more accelerated progression of coronary artery disease a nd a more diffuse narrowing of the coronary arteries, Intracoronary ul trasound can clarify if this is due to less compensatory coronary arte ry enlargement as a response to atherosclerosis,Methods and results Te n non-diabetic: and 15 diabetic patients with coronary artery disease, with angiographically determined one- or mio-vessel disease, underwen t intracoronary ultrasound examination of the non-stenotic coronary ar tery, Forty-five sites with luminal stenosis, detected by intracoronar y ultrasound, were analysed (15 in nondiabetics, 30 in diabetics). Ves sel and lumen area, atherosclerotic plaque area and plaque composition were evaluated. Vessel area was also measured proximal and distal to the healthy segment. In the diabetic patients, there was less vessel a rea increase from the proximal healthy segment into the atheroscleroti c segment than in the nondiabetic patients (99% separate-variance conf idence intervals for differences between diabetics' and non-diabetics' means=0.29 mm(2), 2.71 mm(2)). The proximal plaque foe vessel area, t he atherosclerotic plaque area and plaque composition were similar bet ween the two groups. Conclusion Diabetics with atherosclerosis have le ss compensatory coronary artery enlargement than non-diabetics. This m ay explain the diffuse and accelerated course of coronary artery disea se in these patients.