Understanding timely STEMI treatment performance: A 3-year retrospective cohort study using diagnosis-to-balloon-time and care subintervals.

Objective From the perspective of percutaneous coronary intervention (PCI) centers, locations of ST-segment elevation myocardial infarction (STEMI) diagnosis can include a referring facility, emergency medical services (EMS) transporting to a PCI center, or the PCI center's emergency department (ED). This challenges the use of door-to-balloon-time as the primary evaluative measure of STEMI treatment pathways. Our objective was to identify opportunities to improve care by quantifying differences in the timeliness of STEMI treatment mobilization based on the location of the diagnostic ECG. Methods This 3-year, single-center, retrospective cohort study classified patients by diagnostic ECG location: referring facility, EMS, or PCI center ED. We quantified door-to-balloon-time and diagnosis-to-balloon-time with its care subintervals. Results Of 207 ED STEMI patients, 180 (87%) received PCI. Median diagnosis-to-balloon-times were shortest among the ED-diagnosed (78 minutes [interquartile range (IQR), 61-92]), followed by EMS-identified patients (89 minutes [IQR, 78-122]), and longest among those referred (140 minutes [IQR, 119-160]), reflecting time for transport to the PCI center. Conversely, referred patients had the shortest median door-to-balloon-times (38 minutes [IQR, 34-43]), followed by the EMS-identified (64 minutes [IQR, 47-77]), whereas ED-diagnosed patients had the longest (89 minutes [IQR, 70-114]), reflecting diagnosis and catheterization lab activation frequently occurring before PCI center ED arrival for referred and EMS-identified patients. Conclusions Diagnosis-to-balloon-time and its care subintervals are complementary to the traditional door-to-balloon-times as measures of the STEMI treatment process. Together, they highlight opportunities to improve timely identification among ED-diagnosed patients, use of out-of-hospital cath lab activation for EMS-identified patients, and encourage pathways for referred patients to bypass PCI center EDs.