Effectiveness of Thrombus Aspiration in Plaque Reduction for Patients With Acute Coronary Syndromes
Condition: Acute Coronary Syndrome
MeSH terms: Acute Coronary Syndrome; Thrombosis; Syndrome
Study type: Observational

Summary: 
      Although successful, percutaneous coronary interventions (PCI) with stent implantation may be
      hampered by periprocedural myocardial necrosis. In acute ST-elevation myocardial infarction
      (STEMI), the reduction of thrombus burden through manual thrombus aspiration (TA) of an
      occluded coronary artery has been documented to produce an improved myocardial perfusion rate
      and significant survival advantage. To date, beyond feasibility and safety studies no
      clinical benefit has been yet documented with the use of TA before stent deployment in the
      setting of acute coronary syndromes (ACS) outside acute STEMI. The investigators hypothesize
      that TA before stent deployment reduces the thrombus/plaque burden - as assessed by
      intravascular imaging systems - in the setting of acute coronary syndromes (ACS) outside
      acute STEMI.
    

Detailed description: 
      Periprocedural myocardial infarction (MI) has an independent adverse prognostic relevance.
      Several trials have documented a reduction in the occurrence of periprocedural MI through
      various pharmacological strategies, with enhanced inhibition of platelet aggregation or high
      dose statins. However, real-world registries still document an incidence of periprocedural MI
      in 30-40% of patients. Currently available intravascular imaging techniques, Intravascular
      Ultrasound (IVUS) and more recently available Optical Coherence Tomography (OCT) allow a
      precise evaluation of the coronary plaque and can be extremely useful for monitoring plaque
      modifications obtained with thrombus aspiration (TA). Plaque burden will be assessed as
      plaque + media (P+M), commonly measured with IVUS by subtracting lumen (L) to external
      elastic membrane (EEM) cross sectional area (P+M= EEM-L).

      Expecting a mean plaque volume of 160±50 mm3 in a population of patients with ACS undergoing
      PCI, a sample size of at least 45 patients (52 lesions) with a recent (<15 days, but after 24
      hours) STEMI or a non-ST elevation (NSTE)-ACS within 72 hours of symptoms would provide a 90%
      power to detect a 20% reduction in the plaque volume after TA with an alpha (probability
      value) of 0.05.
    

Observational model: Cohort
Sampling method: Probability Sample
Study population: 
        45 patients with at least one "culprit" lesion, identified as a high-grade (>90%) lesion in
        the territory of jeopardized myocardium, at coronary angiography performed for a recent
        (<15 days, but after 24 hours) STEMI or a non-ST elevation (NSTE)-ACS within 72 hours of
        symptoms.
      
Biospecimen description: 
      Histopathology assessment of aspirated material during manual TA. Quantitative analysis: size
      and weight. Qualitative evaluation: a) thrombus containing only platelets, b) a thrombus with
      an erythrocyte component c) any fragment of vessel wall, cholesterol crystals, inflammatory
      cells or collagen tissue
    
Keywords: NSTE-ACS; PCI; Thrombus Aspiration; IVUS; Periprocedural Myocardial Infarction