title: Time-dependent benefit of initial thrombosuction on myocardial reperfusion in primary percutaneous coronary intervention.
abstract: BACKGROUND
  In ST-segment elevation acute myocardial infarction (STEMI), dislodgement of thrombus within the culprit artery during primary percutaneous coronary intervention (PCI) may cause distal embolisation and impaired myocardial reperfusion. Clinical results of thromboembolic protection strategies have been controversial. We conducted this study to investigate whether the benefit of thrombus removal is time dependent.
  
  
  METHODS
  Seventy-four STEMI patients within 12 h from onset were randomised to receive either primary PCI with initial thrombosuction (IT) or standard strategy. Results were analysed in subgroups according to the onset-to-lab time intervals (subgroup 1: 0-240 min, subgroup 2: 241-480 min and subgroup 3: 481-720 min).
  
  
  RESULTS
  The primary end-points were improvements in thrombolysis in myocardial infarction flow (DeltaTIMI) and myocardial blush grade (DeltaMBG) postprocedure. Better DeltaTIMI (2.2 +/- 1.1 vs. 1.5 +/- 1.3, p = 0.014) and DeltaMBG (2.3 +/- 1.1 vs. 1.0 +/- 1.5, p < 0.001) were observed in IT patients, compared with standard PCI patients. In onset-to-lab time subgroup analysis, the difference between IT and standard PCI is significant only in subgroup 2 (DeltaTIMI 2.6 +/- 1.0 vs. 1.3 +/- 1.2, p = 0.007; DeltaMBG 2.6 +/- 0.9 vs. 1.0 +/- 1.1, p = 0.010), but not in the other two subgroups.
  
  
  CONCLUSIONS
  This prospective randomised study shows that primary PCI with IT may improve epicardial flow and myocardial reperfusion in patients with STEMI, and this benefit is the most significant in patients treated within 4-8 h after symptom onset.
authors: Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors: C-L
authors: CL
authors: Chao
authors: C-S
authors: CS
authors: Hung
authors: Y-H
authors: YH
authors: Lin
authors: M-S
authors: MS
authors: Lin
authors: L-C
authors: LC
authors: Lin
authors: Y-L
authors: YL
authors: Ho
authors: C-P
authors: CP
authors: Liu
authors: C-H
authors: CH
authors: Chiang
authors: H-L
authors: HL
authors: Kao
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D003328:Coronary Thrombosis / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000628:therapy*; D015425:Myocardial Reperfusion / Q000379:methods*; D011446:Prospective Studies; D013396:Suction / Q000379:methods; D017131:Thrombectomy / Q000379:methods; D013997:Time Factors