Process Metrics and Outcomes in Rural vs Urban ST-Elevation Myocardial Infarction

Patients with ST-segment elevation myocardial infarction (STEMI) living in rural settings vs those living in urban settings are less likely to receive primary percutaneous coronary intervention (PPCI), more likely to receive fibrinolytics, and face longer time to reperfusion. These findings were published in the Journal of the American Medical Association Cardiology.

Investigators sought to evaluate clinical characteristics, outcomes, and process metrics in patients with STEMI and compare patients living in rural vs urban settings in the United States (US). The primary outcomes were in-hospital mortality and time-to-reperfusion metrics.

They initiated a cross-sectional multicenter review of the National Cardiovascular Data Registry Chest Pain–MI Registry in 686 US hospitals from January 2019 through June 2020. This review included 70,424 adult patients with STEMI. Among these patients (median age 63 years [IQR, 54-73]; 29.2% women; 85.4% White, 9.6% Black, 7.5% Hispanic or Latino ethnicity, 3.0% Other) 28.0% lived in rural zip codes and 72.0% lived in urban zip codes. More White patients lived in rural areas (91.2% vs 83.1%), and more Black patients lived in urban areas (11.0% vs 5.9%). The most frequent comorbidities were diabetes, dyslipidemia, and hypertension.

The investigators noted that among patients living in rural areas, 37.6% were treated in rural hospitals, 46.8% in urban hospitals, and 15.6% in suburban hospitals. Of patients living in urban areas, 92.0% were treated in urban hospitals. Patients from urban areas were more likely to present to the emergency department (82.2% vs 56.7%) and those living in rural areas were more likely to present directly to the cardiac catheterization laboratory (34.7% vs 15.4%; all P <.001).

The investigators found that patients from rural settings (73.2%) were less likely to receive PPCI vs patients from urban settings (85.1%; P <.001) and more likely to receive fibrinolytics (rural 19.7% vs urban 2.7%; P <.001). Among the patients receiving PPCI, those in rural settings faced longer median time from first medical contact to catheterization activation (rural 30 minutes vs urban 22 minutes), longer median time from first medical contact to device (rural 99 minutes vs urban 81 minutes) including those who transferred to PPCI centers from other care centers (rural 125 minutes vs urban 103 minutes) and those who arrived directly at PPCI centers (rural 83 minutes vs urban 78 minutes; all P <.001).

The investigators noted that, among patients transferring in, those in rural settings faced longer median door-in-door-out time (rural 63 minutes vs urban 50 minutes). They observed patients from urban settings were more likely to present with heart failure (urban 8.1% vs rural 6.7%) and more had out-of-hospital cardiac arrest (urban 6.1% vs rural 4.9%; all P <.001). Analysis after multivariable adjustment showed no significant difference between rural and urban groups in in-hospital mortality (adjusted odds ratio, 0.97; 95% CI, 0.89-1.06).

Study limitations include possible hospital participation bias. Also, zip codes do not necessarily reflect accurate patient locations and there are approximately a fifth of patients who were excluded due to missing zip codes.

The investigators wrote that patients “living in rural settings less frequently received PPCI and more often received fibrinolysis for reperfusion. Despite delays and longer times to reperfusion in the rural cohort compared with the urban cohort, there was no difference in adjusted in-hospital mortality between the 2 groups.”

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.