title: Novel drug-delivery stent: intravascular ultrasound observations from the first human experience with the QP2-eluting polymer stent system.
abstract: BACKGROUND
  The aim of this study was to use serial intravascular ultrasound (IVUS) to evaluate the long-term effect of stent-based 7-hexanoyltaxol (QP2, a taxane analogue) delivery on neointimal tissue growth within the stent and on vessel dimensions at the adjacent reference segments.
  
  
  RESULTS
  Serial IVUS analyses (immediately after intervention and at follow-up at 8.3 months) were performed in 15 native coronary lesions treated with the QuaDS-QP2 stent. IVUS measurements were performed at 8 cross-sections in each target segment (4 cross-sections within the stent and 2 cross-sections in each reference segment). At baseline, no significant plaque protrusion or thrombus was detected in the target segment. Mild incomplete stent apposition and edge dissection were observed in one and two cases, respectively. Percent expansion of the stent (minimum stent area/average reference lumen area) was 96.0+/-21.7%. At follow-up, mean neointimal area within the stent was 1.2+/-1.3 mm(2), and mean cross-sectional narrowing (neointimal area/stent area) was 13.6+/-14.9%. At the vessel segments immediately adjacent to the stent, a significant increase in plaque area (1.9+/-2.6 mm(2), P=0.001) was observed, but vessel area remained unchanged. However, no patients showed clinically significant in-stent or edge restenosis (diameter stenosis >/=50%) during the follow-up period.
  
  
  CONCLUSIONS
  The first human experience with the new drug-delivery stent showed a minimal amount of neointimal proliferation in the stented segment. Late lumen loss at the reference sites adjacent to the stent was acceptable and predominantly due to plaque proliferation.
authors.affiliation: Center for Research in Cardiovascular Interventions, Stanford University, Stanford, California, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Honda
authors.forename: E
authors.initials: E
authors.lastname: Grube
authors.forename: L M
authors.initials: LM
authors.lastname: de La Fuente
authors.forename: P G
authors.initials: PG
authors.lastname: Yock
authors.forename: S H
authors.initials: SH
authors.lastname: Stertzer
authors.forename: P J
authors.initials: PJ
authors.lastname: Fitzgerald
mesh_terms: D000328:Adult; D000368:Aged; D001952:Bridged-Ring Compounds / Q000494:pharmacology; D003327:Coronary Disease / Q000188:drug therapy / Q000473:pathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology; D016503:Drug Delivery Systems / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011108:Polymers; D015607:Stents; D017539:Tunica Intima / Q000187:drug effects / Q000473:pathology; D018084:Ultrasonography, Interventional
chemical_list: D001952:Bridged-Ring Compounds; D011108:Polymers; C434083:7-hexanoyltaxol