LAUSR

BACKGROUND Patients presenting with acute coronary syndrome (ACS) from left main (LM) disease are at a high risk for mortality despite recent advancement in devices and techniques during percutaneous coronary interventions (PCI). We aimed to evaluate patient characteristics, clinical presentations, and key clinical characteristics associated with adverse in-hospital outcomes among ACS patients undergoing LM-PCI. METHODS We retrospectively identified 280 LM-ACS patients (3.7 %) from 7608 ACS patients in the prospective multicenter Japan Cardiovascular Database-Keio Inter-Hospital Cardiovascular Studies registry from March 2009 to May 2016 and divided them into those with/without PCI/coronary artery bypass grafting. We compared baseline demographics, coronary lesion characteristics, PCI details, and short-term outcomes, including in-hospital mortality and periprocedural complications, between the two groups. RESULTS Among LM-ACS patients, 38.6 % presented with ST elevation myocardial infarction, 29.6 % with cardiogenic shock (CS), and 15.4 % with cardiac arrest. The observed in-hospital mortality rate was 18.9 % with presence of CS [odds ratio (OR): 10.16, 95 % confidence interval (CI): 4.51-22.91, p<0.001] and absence of prior revascularization (de novo patients; OR: 4.31, 95 % CI: 1.43-12.94, p=0.009) was independently associated with higher incidence of in-hospital mortality. Notably, the observed mortality rate was substantially higher among de novo patients than the predicted mortality rate with a contemporary risk model (observed: 25.1 %; predicted: 11.6 %). CONCLUSIONS Prior revascularization act as a protective factor among LM-ACS patients in the contemporary era of PCI. Further studies to detect those at higher risk for LM coronary lesion progression are needed to fully implement these findings into clinical practice.