Temporal changes in patient characteristics and outcomes in ST-segment elevation myocardial infarction 2003-2018

Background: We sought to describe changes in demographic variables, process of care measures, and outcomes of patients treated in a regional ST-segment elevation myocardial infarction (STEMI) program over the last 15 years.

Methods: We describe demographic variables, process of care measures, and outcomes of patients treated in the program in various 5-year time periods: 2003-2007 (n = 1,821), 2008-2012 (n = 1,968), and 2013-2018 (n = 2,223). The primary outcome measures were in-hospital and 30-day mortality.

Results: Among 6,012 STEMI patients treated from 2003 to 2018 we observed a significant increase in mean age at presentation (62 ± 14 to 64 ± 13 years) and diabetes (14-22%, p < .01). The proportion of patients with cardiogenic shock (CS) and cardiac arrest (CA) pre-PCI increased significantly from 9.5% to 11.1% and 8.5% to 12.7% (p < .05), respectively. The median door-to-balloon (D2B) times decreased from 98 to 93 min and total ischemic time decreased from 202 to 185 min (all p < .05). Despite increased patient complexity, the proportion of nontransfer and transfer patients achieving D2B times consistent with guideline recommendations remained unchanged (for nontransfer patients 79-82%, p = .45 and for transfer patients 65-64%, p = .34). Among all STEMI patients, in-hospital mortality increased during the study period from 4.9 to 6.9% (p = .007) but remained stable (<2%) when CA and CS patients were excluded.

Conclusions: Over the last 15 years, short-term STEMI mortality has increased despite improvements in care delivery metrics. Patients with CA and/or CS now represent 10% of STEMI patients and are responsible for 80% of deaths. Therefore, efforts to improve STEMI mortality, and metrics for assessing STEMI programs, should focus on these patients.