title: Association between silent embolic cerebral infarction and continuous increase of P2Y12 reaction units after neurovascular stenting.
abstract: OBJECTIVE
  Endovascular procedures are one of the important treatment options for steno-occlusive arteries in ischemic stroke patients. However, embolic complications after such procedures are always a concern. The authors investigated the association between serial change of residual platelet reactivity and silent embolic cerebral infarction (SECI) after endovascular treatment.
  
  
  METHODS
  Ischemic stroke patients undergoing stenting of intra- or extracranial arteries were recruited prospectively. Residual platelet reactivity, represented by aspirin reaction units (ARUs) and P2Y12 reaction units (PRUs), was measured serially (6 hours before, immediately after, and 24 hours after the procedure). A loading dosage of aspirin (500 mg) and/or clopidogrel (300 mg) was given 24 hours before the procedure to patients naïve to antiplatelet agents, whereas the usual dosage (aspirin 100 mg and clopidogrel 75 mg) was continued for patients who had previously been taking these agents for more than a week. Diffusion-weighted MRI was performed before and 24 hours after the procedure to detect new SECIs. Clinical characteristics, baseline ARU and PRU values, and the change in ARU and PRU values after stenting were compared between patients with and without SECIs.
  
  
  RESULTS
  Among 69 consecutive patients who underwent neurovascular stent insertion, 41 patients (59.4%) had poststenting SECIs. The lesion was located only at the vascular territory of the stented vessel in 21 patients (51.2%), outside the stented vessel territory in 8 patients (19.5%), and both inside and outside in 12 patients (29.3%). The occurrence of SECIs was not associated with the baseline ARU or PRU value, but was associated with PRU increase after stenting (36 ± 73 vs -12 ± 59, p = 0.007), deployment of a longer stent (31.1 ± 16.5 mm vs 21.8 ± 9.9 mm, p = 0.01), and stent insertion in extracranial arteries (78.1% vs 45.2%, p = 0.008). Stent length (OR 1.066, p = 0.01) and PRU change (OR 1.009, p = 0.04) were independently associated with the occurrence of SECI.
  
  
  CONCLUSIONS
  Residual platelet reactivity after dual antiplatelet treatment measured before stenting did not predict poststenting SECI. However, the longer stent and the serial increase of PRU values after stenting were related to SECI. Continuous increase of platelet activation after endovascular procedure may be important in poststent cerebral infarction.
authors.affiliation: Departments of Radiology and.
authors.forename: Bum Joon
authors.initials: BJ
authors.lastname: Kim
authors.forename: Joo Y
authors.initials: JY
authors.lastname: Kwon
authors.forename: Jin-Man
authors.initials: JM
authors.lastname: Jung
authors.forename: Deok Hee
authors.initials: DH
authors.lastname: Lee
authors.forename: Dong-Wha
authors.initials: DW
authors.lastname: Kang
authors.forename: Jong S
authors.initials: JS
authors.lastname: Kim
authors.forename: Sun U
authors.initials: SU
authors.lastname: Kwon
mesh_terms: D001241:Aspirin / Q000627:therapeutic use*; D002544:Cerebral Infarction / Q000209:etiology* / Q000517:prevention & control*; D000077144:Clopidogrel; D004351:Drug Resistance; D057510:Endovascular Procedures / Q000009:adverse effects*; D005260:Female; D006801:Humans; D020766:Intracranial Embolism / Q000209:etiology* / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D011446:Prospective Studies; D058921:Purinergic P2Y Receptor Antagonists / Q000627:therapeutic use*; D015607:Stents / Q000009:adverse effects*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D058921:Purinergic P2Y Receptor Antagonists; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin
keywords: ARU = aspirin reaction unit; DWI = diffusion-weighted imaging; ECAS = extracranial atherosclerotic stenosis; ICAS = intracranial atherosclerotic stenosis; PRU = P2Y12 reaction unit; SECI = silent embolic cerebral infarction; embolic infarction; neurovascular stenting; residual platelet reactivity; vascular disorders