title: Feasibility and repeatability of optical coherence tomography measurements of pre-stent thrombus burden in patients with STEMI treated with primary PCI.
abstract: OBJECTIVE
  Intracoronary thrombus is disrupted by stent deployment and confounded by the development of intrastent plaque prolapse. This study aims at investigating the feasibility and repeatability of thrombus quantification prior to stent implantation using optical coherence tomography (OCT) in ST-segment elevation myocardial infarction (STEMI) patients.
  
  
  RESULTS
  Patients were enrolled in an OCT substudy of the TOTAL trial (a randomized trial of routine aspiration ThrOmbecTomy with PCI vs. PCI ALone in patients with STEMI undergoing primary PCI) of aspiration thrombectomy or percutaneous coronary intervention (PCI) alone in primary PCI (PPCI) of STEMI. Using OCT, thrombus burden (TB) and other measures of pre- and post-stent atherothrombus were analysed over the arterial segment defined by the final stent length. Feasibility was 86.2% (25/29 patients) for both pre- and post-stent OCT imaging. Altogether, 8111 OCT cross-sections were analysed. In Bland-Altman analyses of inter-observer variation (n = 25), the mean pre-stent TB was 8.76% for Observer 1 and 8.97% for Observer 2 (limits of agreement -2.6 to 2.2%). In Bland-Altman analyses of intra-observer variation (n = 15), the mean pre-stent TB was 8.06% for the first and 7.35% for the second round of analysis by Observer 1 (limits of agreement -1.72 to 3.15%). There was a good correlation between pre-stent TB and pre-stent quadrants with thrombus/mm (r = 0.97), but only modest correlation between pre-stent TB and post-stent atherothrombotic burden (ATB; r = 0.54).
  
  
  CONCLUSIONS
  Measurement of pre-stent TB by OCT during the PPCI of STEMI is feasible and highly repeatable. Pre-stent TB is only modestly correlated with post-stent ATB, which indicates that pre-stent measurements might be of additional value when assessing the TB in STEMI.
authors.affiliation: Heart Hospital, Tampere University Hospital and School of Medicine, University of Tampere, PO Box 2000, Teiskontie 35, Tampere FI-33521, Finland olli.kajander@sydansairaala.fi.
authors.forename: Olli A
authors.initials: OA
authors.lastname: Kajander
authors.affiliation: Heart Hospital, Tampere University Hospital and School of Medicine, University of Tampere, PO Box 2000, Teiskontie 35, Tampere FI-33521, Finland.
authors.forename: Laura S
authors.initials: LS
authors.lastname: Koistinen
authors.affiliation: Heart Hospital, Tampere University Hospital and School of Medicine, University of Tampere, PO Box 2000, Teiskontie 35, Tampere FI-33521, Finland.
authors.forename: Markku
authors.initials: M
authors.lastname: Eskola
authors.affiliation: School of Health Sciences, University of Tampere, Tampere, Finland.
authors.forename: Heini
authors.initials: H
authors.lastname: Huhtala
authors.affiliation: Royal North Shore Hospital, Sydney, Australia.
authors.forename: Ravinay
authors.initials: R
authors.lastname: Bhindi
authors.affiliation: Heart Hospital, Tampere University Hospital and School of Medicine, University of Tampere, PO Box 2000, Teiskontie 35, Tampere FI-33521, Finland.
authors.forename: Kari
authors.initials: K
authors.lastname: Niemelä
authors.affiliation: McMaster University and Population Health Research Institute, Hamilton Health Sciences, Hamilton, Canada.
authors.forename: Sanjit S
authors.initials: SS
authors.lastname: Jolly
authors.affiliation: McMaster University and Population Health Research Institute, Hamilton Health Sciences, Hamilton, Canada.
authors.forename: Tej
authors.initials: T
authors.lastname: Sheth
mesh_terms: D000368:Aged; D003131:Combined Modality Therapy; D016001:Confidence Intervals; D017023:Coronary Angiography / Q000379:methods; D003328:Coronary Thrombosis / Q000175:diagnosis* / Q000628:therapy; D004562:Electrocardiography; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000628:therapy; D015588:Observer Variation; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects / Q000379:methods*; D011182:Postoperative Care / Q000379:methods; D011300:Preoperative Care / Q000379:methods; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D015607:Stents; D017131:Thrombectomy / Q000379:methods*; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome
keywords: Aspiration thrombectomy; Optical coherence tomography; Primary percutaneous coronary intervention; ST segment elevation myocardial infarction; Thrombus burden