Impact of Comprehensive STEMI Protocol on Process Metrics and Clinical Outcomes in STEMI Patients With Nonsystem Delays.

Hospital-wide strategies improve outcomes in STEMI, yet their impact on patients with nonsystem delays (NSD) to primary PCI remains unknown. This study evaluated the effect of a 4-step comprehensive STEMI protocol (CSP) on outcomes in this high-risk population. This observational cohort analysis included STEMI patients with NSD as defined by the ACC National Cardiovascular Data Registry CathPCI Registry v5.0 criteria, which included difficult vascular access, difficulty crossing the culprit lesion, cardiac arrest and/or need for intubation before PCI, patient delays in providing consent for PCI, emergent placement of left-ventricular support device before PCI, and other reasons. Process and outcome metrics were compared before (January, 2011-July, 2014; n = 163) and after (July, 2014-July, 2019; n = 196) CSP implementation. The CSP comprised: (1) emergency department catheterization-laboratory activation; (2) STEMI Safe Handoff Checklist; (3) immediate transfer to an available laboratory; and (4) radial-first PCI. Among 359 patients with NSD, CSP implementation increased pre-PCI guideline-directed medical therapy (57.1%-79.6%, p <0.001) and radial access (16.6%-55.6%, p <0.001), and reduced median door-to-balloon time (132-101 minutes, p = 0.001). Post-CSP patients experienced lower rates of bleeding (22.7%-10.2%, p = 0.002), cardiac arrest (36.2%-23.5%, p = 0.01), circulatory shock (39.9%-24.5%, p = 0.003), and acute kidney injury (30.7%-19.9%, p = 0.03), with more frequent discharge to home (65.0%-78.6%, p = 0.006). In-hospital mortality was similar (14.1% vs 9.2%, p = 0.20). In conclusion, a 4-step CSP improved process metrics and clinical outcomes among STEMI patients with NSD, challenging the notion that outcomes of NSD cohort are unmodifiable and underscoring the importance of system-based interventions in this high-risk cohort.