Treatment delay in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction: A key process analysis of patient and program factors

Background: Most hospitals that perform primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) in the United States exceed the recommended door-to-balloon time. There is heightened interest in identifying and eliminating factors that introduce delay. Methods: We performed a key process analysis of our primary PCI program, assessed the relative contribution of individual time intervals on total ischemic time, and identified predictors of delay. Results: Median times and predictors of delay within each time interval were determined for the entire STEMI cohort ("real world") and after exclusion of patients with atypical symptoms and/or presentations of STEMI that resulted in inherent delay in diagnosis and treatment ("ideal world"). Delays in therapy were symptom onset to presentation (120 minutes [interquartile range, IQR, 60-310 minutes, ideal world] and 150 minutes [IQR 60-360 minutes, real world]; predictors of delay were peripheral vascular disease, self-transportation, daytime and weekend presentation); door-to-balloon time (118.5 minutes [IQR 96-141 minutes, ideal world] and 125 minutes [IQR 100-170 minutes, real world]; predictors of delay were female sex, previous stroke, nighttime and weekend presentation, and cardiogenic shock); and symptom onset to first balloon inflation (272 minutes [IQR 187-465 minutes, ideal world] and 297 minutes [IQR 198-560 minutes, real world]; predictors of delay were peripheral vascular disease, weekend presentation, and self-transportation). Conclusions: Key process analysis of a primary PCI program identifies treatment delays unique to the hospital and the patient population it serves.