Comparison of coronary stent expansion by intravascular ultrasonic imagingin younger versus older patients with diabetes mellitus

The poor long-term outcome in young diabetic patients receiving stents is n ot well understood. The purpose of this study was to characterize the postp rocedural results of stent placement in diabetic patients using intravascul ar ultrasound to identify factors that might be associated with poor clinic al outcome. The acute dimensions from intravascular ultrasound studies afte r stent deployment at 5 sites were measured from 39 coronary segments from patients with diabetes mellitus (DM) and 161 segments from nondiabetic pati ents (non-DM), Within these 2 groups, segments were subgrouped into young ( y) and old (o) in reference to the mean study age of 64 years, forming 4 gr oups: yDM (n = 20), y non-DM (n = 65), oDM (n = 19), and a non-DM (n = 96), Results are reported as mean +/- 1 SD. Diabetic patients had smaller mean lumen area within the treated segment than o non-DM (8.37 +/- 2.59 vs 9.11 +/- 3.35 mm(2), p <0.01), These differences were more pronounced at the dis tal reference vessel lumen of yDM than y non-DM (7.6 +/- 2.3 vs 10.3 +/- 4. 5 mm(2), p <0.003), and were associated with greater percent plaque area in the distal reference vessel (43.4 +/- 13% vs 34.1 +/- 11.2%, p <0.003). In young diabetic patients undergoing elective stent placement, underexpansio n of the stented segment is common, which may contribute to the relatively poor long-term outcome in these patients. We suggest that when stenting is the procedure of choice in this subgroup of high-risk patients, special att ention should be given to optimizing lumen dimensions. (C)2000 by Excerpta Medica, Inc.