ENHANCED SECRETION OF INSULIN PLAYS A ROLE IN THE DEVELOPMENT OF ATHEROSCLEROSIS AND RESTENOSIS OF CORONARY-ARTERIES - ELECTIVE PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY IN PATIENTS WITH EFFORT ANGINA

Objectives. We investigated the relation between insulin and coronary atherosclerosis and restenosis of the coronary arteries, by performing elective percutaneous transluminal coronary angioplasty (PTCA). Backg round. Insulin is known to promote atherosclerosis of the arteries and has been implicated in the development of restenosis after PTCA. Meth ods. Of 210 angina patients who underwent PTCA, newly detected lesions in 35 consecutive nondiabetic subjects without previous intervention on the same main coronary arteries were analyzed after a 75-g oral glu cose tolerance test (OGTT) and follow-up coronary angiography. Atheros clerotic lesions were evaluated by pattern, severity and extent. Reste nosis was defined as loss of gain, the percentage of loss of the initi al gain in the coronary diameter achieved by PTCA greater than or equa l to 50%. Results. Patients with restenosis had a significantly higher extent index (a marker of atherosclerosis), insulin area, ratio of in sulin area to glucose area, insulinogenic index and minimal lumen diam eter after PTCA than those without restenosis (p = 0.001, 0.011, 0.002 , 0.016 and 0.011, respectively). Simple regression analysis revealed that only the ratio of insulin area to glucose area (a relative marker of enhanced insulin secretion) significantly correlated with the exte nt index (p = 0.035). Extent index, insulin area, the ratio of insulin area to glucose area and insulinogenic index significantly correlated with loss of gain (p = 0.001, 0.010, 0.002 and 0.032, respectively), Stepwise multiple regression analyses revealed that extent index and t he ratio of insulin area to glucose area significantly correlated with loss of gain. Conclusions. Enhanced secretion of insulin during the O GTT might be useful as a predictor of coronary atherosclerosis and of restenosis after elective PTCA in nondiabetic patients with effort ang ina. (J Am Coll Cardiol 1998;32:1624-9) (C)1998 by the American Colleg e of Cardiology.