Risk, Management, and Outcomes in PCI-Treated Acute Coronary Syndrome With Cardiogenic Shock

BACKGROUND: Acute coronary syndrome complicated by cardiogenic shock (ACS-CS) remains associated with high mortality despite advances in percutaneous coronary intervention (PCI) and increasing attention to mechanical circulatory support (MCS). OBJECTIVES: This study aimed to evaluate temporal trends in patient risk profiles, treatment strategies, and in-hospital outcomes among patients undergoing PCI for ACS-CS. METHODS: From 2009 to 2019, 24,527 consecutive PCI procedures were recorded in the Keio Interhospital Cardiovascular Studies-PCI registry, including 870 cases (3.5%) with ACS-CS. Patients were categorized into 4 time periods (T1: 2009-2011; T2: 2012-2013; T3: 2014-2016; T4: 2017-2019). Temporal changes in risk profiles were evaluated using National Cardiovascular Data Registry Catheterization PCI mortality and bleeding risk scores. Trends in MCS use, in-hospital mortality, and post-PCI complications were analyzed. RESULTS: Predicted in-hospital mortality and bleeding risk remained stable over time, at approximately 20% (P for trend = 0.053) and 40% (P for trend = 0.39), respectively. Overall MCS use declined from 66.5% in T1 to 56.7% in T4, primarily due to reduced intra-aortic balloon pump use (46.5% to 31.2%). Despite these changes in management, crude and National Cardiovascular Data Registry risk-adjusted in-hospital mortality remained persistently high at approximately 30% throughout the study period. CONCLUSIONS: Among patients with ACS-CS selected for PCI in a multicenter Japanese registry, management strategies changed substantially over the past decade, particularly regarding MCS utilization. However, no significant temporal improvement in in-hospital mortality was observed, underscoring the persistent clinical challenges of this high-risk PCI-treated population.