Hospital delays in reperfusion for ST-elevation myocardial infarction : Implications when selecting a reperfusion strategy

It has been suggested that the survival benefit associated with primary percutaneous coronary intervention (PPCI) in ST-segment elevation myocardial infarction may be attenuated if door-to-balloon (DB) time is delayed by >1 hour beyond door-to-needle (DN) times for fibrinolytic therapy. Whereas DB times are rapid in randomized trials, they are often prolonged in routine practice. We hypothesized that in clinical practice, longer DB-DN times would be associated with higher mortality rates and reduced PPCI survival advantage. We also hypothesized that in addition to PPCI delays, patient risk factors would significantly modulate the relative survival advantage of PPCI over fibrinolysis. DB-DN times were calculated by subtracting median DN time from median DB time at a hospital using data from 192,509 patients at 645 National Registry of Myocardial Infarction hospitals. Hierarchical models that adjusted simultaneously for both patient-level risk factors and hospital-level covariates were used to evaluate the relationship between PCI-related delay, patient risk factors, and in-hospital mortality. Longer DB-DN times were associated with increased mortality (P