Prevalence and prognosis of coronary stent gap detected by multi-detector CT: a follow-up study.

Abstract

To evaluate the features of stent gap (SG) and the long-term impact of SG on in-stent restenosis (ISR) in patent stents. A total of 347 consecutive patients with 781 stents who underwent MDCT were assessed for SG and ISR. Clinical and stent features were compared between the SG and non-SG groups. In the follow-up study, among 82 patients with 175 patent stents [26 assessed by conventional coronary angiography (CCA) including 6 contacted in a telephone survey, 46 assessed by computed tomography angiography (CTA) and 10 by both], the incidence of ISR was compared between stents with and without SG. Three patients and 13 stents were excluded. SG was observed in 12.5% of patients and 8.6% of stents. ISR detected by CTA was noted in 21.2% of SG, and SG accounted for 23.7% of ISR. Stent number, length, location, overlapping pattern, tortuosity and in-out angle were predisposing factors for SG. During a mean follow-up period of 15 months after detection of SG, the incidence of ISR was significantly higher in the SG group than in the non-SG group (43.8/14.9% by CCA, 33.3/10.1% by CTA and CCA). Patent stents with SG detected by CTA had a higher incidence of late restenosis, indicating that long-term follow-up or further intervention is necessary.