Background: national initiatives have reduced door-to-balloon (DTB) times for direct-arrival ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). However, STEMI patients requiring interhospital transfer for primary PCI are often excluded from public performance assessments of this quality metric.
Methods: we compared DTB time improvements between 2005 and 2007 for 29,248 transfer (25%) and 86,382 direct-arrival STEMI patients treated with primary PCI at 790 hospitals in the National Cardiovascular Data Catheterization PCI Registry. Among the 165 hospitals that submitted data for ≥10 patients per year, we examined the correlation between hospital-level changes in transfer and direct-arrival DTB times.
Results: although DTB times decreased significantly over time for both groups, transfer STEMI patients had longer DTB times (median 149 vs 79 minutes, P < .0001), few received PCI ≤90 minutes (10% vs 63%, P < .0001), and the adjusted rate of DTB time improvement was slower (5% vs 9% relative decrease per year, P < .001) compared with direct-arrival patients. Larger annual transfer volume (not necessarily for primary PCI) was associated with greater improvement in transfer DTB times. However, there was no correlation between hospitals that improved direct-arrival DTB times and those that improved transfer DTB times (r = 0.094, P = .23).
Conclusions: although there has been modest temporal improvement in DTB times, transfer patients still rarely achieve benchmark standards. Hospitals that had greater improvements in direct-arrival DTB times were not necessarily those with greater improvements in transfer DTB times. These results highlight the need for targeted system and policy approaches to improve DTB time for transferred primary PCI patients.