title: Correlation of intravascular ultrasound findings with histopathological analysis of thrombus aspirates in patients with very late drug-eluting stent thrombosis.
abstract: BACKGROUND
  Intravascular ultrasound of drug-eluting stent (DES) thrombosis (ST) reveals a high incidence of incomplete stent apposition (ISA) and vessel remodeling. Autopsy specimens of DES ST show delayed healing and hypersensitivity reactions. The present study sought to correlate histopathology of thrombus aspirates with intravascular ultrasound findings in patients with very late DES ST.
  
  
  RESULTS
  The study population consisted of 54 patients (28 patients with very late DES ST and 26 controls). Of 28 patients with very late DES ST, 10 patients (1020+/-283 days after implantation) with 11 ST segments (5 sirolimus-eluting stents, 5 paclitaxel-eluting stents, 1 zotarolimus-eluting stent) underwent both thrombus aspiration and intravascular ultrasound investigation. ISA was present in 73% of cases with an ISA cross-sectional area of 6.2+/-2.4 mm(2) and evidence of vessel remodeling (index, 1.6+/-0.3). Histopathological analysis showed pieces of fresh thrombus with inflammatory cell infiltrates (DES, 263+/-149 white blood cells per high-power field) and eosinophils (DES, 20+/-24 eosinophils per high-power field; sirolimus-eluting stents, 34+/-28; paclitaxel-eluting stents, 6+/-6; P for sirolimus-eluting stents versus paclitaxel-eluting stents=0.09). The mean number of eosinophils per high-power field was higher in specimens from very late DES ST (20+/-24) than in those from spontaneous acute myocardial infarction (7+/-10), early bare-metal stent ST (1+/-1), early DES ST (1+/-2), and late bare-metal stent ST (2+/-3; P from ANOVA=0.038). Eosinophil count correlated with ISA cross-sectional area, with an average increase of 5.4 eosinophils per high-power field per 1-mm(2) increase in ISA cross-sectional area.
  
  
  CONCLUSIONS
  Very late DES thrombosis is associated with histopathological signs of inflammation and intravascular ultrasound evidence of vessel remodeling. Compared with other causes of myocardial infarction, eosinophilic infiltrates are more common in thrombi harvested from very late DES thrombosis, particularly in sirolimus-eluting stents, and correlate with the extent of stent malapposition.
authors.affiliation: Invasive Cardiology, Department of Cardiology, University Hospital Bern, 3010 Bern, Switzerland.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cook
authors.forename: Elena
authors.initials: E
authors.lastname: Ladich
authors.forename: Gaku
authors.initials: G
authors.lastname: Nakazawa
authors.forename: Parham
authors.initials: P
authors.lastname: Eshtehardi
authors.forename: Michel
authors.initials: M
authors.lastname: Neidhart
authors.forename: Rolf
authors.initials: R
authors.lastname: Vogel
authors.forename: Mario
authors.initials: M
authors.lastname: Togni
authors.forename: Peter
authors.initials: P
authors.lastname: Wenaweser
authors.forename: Michael
authors.initials: M
authors.lastname: Billinger
authors.forename: Christian
authors.initials: C
authors.lastname: Seiler
authors.forename: Steffen
authors.initials: S
authors.lastname: Gay
authors.forename: Bernhard
authors.initials: B
authors.lastname: Meier
authors.forename: Werner J
authors.initials: WJ
authors.lastname: Pichler
authors.forename: Peter
authors.initials: P
authors.lastname: Jüni
authors.forename: Renu
authors.initials: R
authors.lastname: Virmani
authors.forename: Stephan
authors.initials: S
authors.lastname: Windecker
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D015415:Biomarkers / Q000378:metabolism; D003324:Coronary Artery Disease / Q000628:therapy*; D003328:Coronary Thrombosis / Q000000981:diagnostic imaging / Q000276:immunology / Q000473:pathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000276:immunology / Q000473:pathology; D054855:Drug-Eluting Stents / Q000009:adverse effects*; D004804:Eosinophils / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017131:Thrombectomy; D018084:Ultrasonography, Interventional; D014657:Vasculitis / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology
chemical_list: D015415:Biomarkers