Value-Based ST-Segment-Elevation Myocardial Infarction Care Using Risk-Guided Triage and Early Discharge

Background: Prior studies suggest that low-risk ST-segment-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention can be considered for early discharge. We describe the implementation of an STEMI risk score to decrease cost while maintaining optimal patient outcomes. Methods and Results: We determined the impact of risk-guided STEMI care on healthcare value through the retrospective application of the Zwolle Risk Score to 967 patients receiving primary percutaneous coronary intervention between 2009 and 2011. Of these patients, 540 (56%) were categorized as low risk, indicating they may be safely triaged directly to a telemetry unit rather than the intensive care unit and targeted for early discharge. We subsequently developed and implemented a modified Zwolle Risk Calculator into the electronic medical record to support application of the fast-track protocol for low-risk STEMI patients. Among 549 prospective patients with STEMI, 62% were low risk, and the fast-track protocol was followed in 75% of cases. Prospective results confirmed lower rates of complications (low risk 8.3% versus high risk 38.7%; P<0.001) and in-hospital mortality (low risk 0.4% versus High risk 12.5%; P<0.001) in the low-risk cohort. Low-risk patients had a shorter median length of stay (median and [25th, 75th percentiles]: low risk 2 [2, 3] versus high risk: 3 [2, 6]; P<0.001) and lower overall costs (low risk $6720 [$5280-$9030] versus high risk $11783 [$7953-$25359]; P<0.001). Low-risk patients treated on-protocol had shorter median length of stay (on-protocol 2 [1, 2] versus off-protocol 2 [2, 3]; P<0.001) and hospital costs (on-protocol $6090 [$4730, $7356] versus off-protocol $11783 [$7953, $25359]; P<0.001) than those treated off-protocol. On-protocol low-risk patients in the prospective cohort also had lower costs and shorter length of stay than low-risk patients in the retrospective cohort (P<0.001 for both). Conclusions: In our study, risk-guided triage and discharge after primary percutaneous coronary intervention for STEMI improved healthcare value by reducing costs of care without compromising quality of care or patient outcomes.