Abstract 9625: Late Malapposition and Endothelial Coverage of Drug-Eluting-Stents - A Prospective Optical Coherence Tomography Study

Abstract

Background: Uncovered stent struts of drug-eluting stents (DES) are associated with late stent thrombosis. Early and late malapposition of stent struts may be the major mechanisms for uncovered struts. Data regarding coverage of malapposed struts are missing. Aims: This study examines malapposition of DES and the coverage of late malapposed struts in patients who underwent elective percutaneous coronary intervention (PCI). Methods: Fifty patients treated with 60 DES (25 Everolimus-eluting stents [EES], 18 Zotarolimus-eluting stents [ZES], 17 Biolimus-eluting stents [BES]) underwent optical coherence tomography (OCT) directly after implantation and after 12 months. Results: Postintervention acute stent malapposition (ASM) occurred in 30 stents (50%). Of these, 21 stents (70%) resolved completely, whereas 6 stents resolved partly and 3 persisted completely after one year. At this time-point, a total of 15 stents (25%) with late stent malappositions (LSM) were detected due to late acquired stent malapposition (LASM) in additional 10 stents (Table 1). Twelve of these 15 stents showed complete or almost complete (>80%) coverage of the malapposed struts, whereas 3 stents had no coverage of any malapposed strut (Table 2). Conclusion: A quarter of electively implanted DES is associated with LSM. Uncoverage of malapposed struts applies only to a minority of stents with LSM. The reason for coverage/uncoverage and the clinical impact has to be determined.