225: Impact of platelet function monitoring and optimization of dual antiplatelet therapy in patients with unprotected left main disease treated by percutaneous coronary intervention: The ALMA Registry

Abstract

Cardiac surgery is the recommended treatment for patients with left main (LM) disease, although percutaneous coronary intervention (PCI) is emerging as an alternative technique. Stent thrombosis (ST) even if rare is a serious complication after PCI with high rate of mortality. Aggregation tests can identify patients with high platelet reactivity under clopidogrel and aspirin. The objective of this registry was to evaluate the 2-years rate of ST and outcomes in patients with PCI for unprotected LM disease and adapted dual antiplatelet therapy (DAPT) according to aggregation tests. Fifty one patients with LM disease were prospectively included in a single center registry. Acute myocardial infarction (MI) and cardiogenic shock were exclusion criteria. DAPT response was evaluated by VASP index and light transmission aggregometry (LTA) with acid arachidonic acid (AA 0.5 mg/ml) and with adenosine diphosphate (ADP 20 µmol/L). Patients were 67±12 years old, 52% were diabetic, 33% admitted for acute coronary syndrome and 61% had multivessel disease. For distal LM lesions (73%), the provisional T-stenting approach was used in all cases with 84% of final kissing balloon inflation and 20% of T stenting. 27% patients were aspirin non responders (LTA-AA 0.5 mg/ml≥20%) and 47% clopidogrel non responders according to VASP index (≥50%). After optimization of DAPT, aspirin was given twice a day in 27% of patients, prasugrel in 45%, clopidogrel high dose (≥150 mg) in 35% and clopidogrel standard dose (75 mg) in only 20%. At 2 years, no ST occurred. Outcomes were 24% with 3 non Q-wave MI (6%), 2 cerebrovascular accidents (4%), and 7 repeat revascularizations (14%) with 4 target lesion revascularization (8%). Mortality rate was 4% (n=2) with one cardiovascular death (2%). Unprotected LM stenting and systematic platelet function assessment with DAPT optimization provides excellent clinical outcomes without any stent thrombosis at 2 years.