Improving Care Pathways for Acute Coronary Syndrome: Patients Undergoing Percutaneous Coronary Intervention

Abstract

Acute coronary syndrome (ACS) admissions are common and costly. The association between comprehensive ACS care pathways, outcomes, and costs are lacking. From 434,172 low-risk, uncomplicated ACS patients eligible for early discharge (STEMI 35%, UA/NSTEMI 65%) from the Premier database, we identified ACS care pathways, by stratifying low-risk, uncomplicated STEMI and UA/NSTEMI patients by access site for PCI (trans-radial intervention [TRI] vs transfemoral intervention [TFI]) and by length of stay (LOS). Associations with costs and outcomes (death, bleeding, acute kidney injury, and myocardial infarction at 1-year) were tested using hierarchical, mixed-effects regression, and projections of cost savings with change in care pathways were obtained using modeling. In low-risk uncomplicated STEMI patients, compared with TFI and LOS ≥3 days, a strategy of TRI with LOS <3 days and TFI with LOS <3 days were associated with cost savings of $6,206 and $4,802, respectively. Corresponding cost savings for UA/NSTEMI patients were $7,475 and $6,169, respectively. These care-pathways did not show an excess risk of adverse outcomes. We estimated that >$300 million could be saved if prevalence of the TRI with LOS <3 days and TFI with LOS <3 days strategies are modestly increased to 20% and 70%, respectively. In conclusion, we demonstrate the potential opportunity of cost savings by repositioning ACS care pathways in low-risk and uncomplicated ACS patients, toward transradial access and a shorter LOS without an increased risk of adverse outcomes.

Figure 1.. Schematic representation of the competing care pathways considered in this study.

Shown at the bottom of each pathway is an acronym-based and color-coded identification of each pathway. The double headed arrows indicate the comparisons conducted herein. Prevalence of each care pathway within the subgroups of STEMI and UA/NSTEMI patients is shown above each pathway acronym.

Figure 2.. Cost reduction associated with the care pathways for ACS.

The bars are color-coded and match the color-coded pathways shown in Figure 2. Error bars indicate 95% confidence intervals. All cost reduction estimates were obtained using 2-level hierarchical, mixed effects linear regression models (separate for cost shown in the Figure) that used the contributing hospital as random effects. The model used inflation adjusted (to 2016 US$) cost as the dependent variable and the following predictor variables: the three care pathways simultaneously compared against the reference pathway, age, female gender, history of PCI, history of congestive heart failure, history of chronic obstructive pulmonary disease, history of diabetes, history of hypertension, multiple vessel affliction, use of bare metal stents, Medicare/Medicaid as the primary insurance payer, number of beds In the hospital, teaching hospital and hospital located in an urban area. Models were run separately for STEMI and UA/STEMI groups. Detailed results are provided in Supplementary Tables 1 and 2.

Figure 3.. Department-wise drivers of total cost reduction based on care pathways.

Results are from 2-level, hierarchical, mixed effects models run separately for the STEMI and UA/NSTEMI groups and for each cost component shown. Model specification was the same as that mentioned in legend to Figure 3. Color-coded numbers show the cost reduction in 2016 US$. Detailed results are provided in Supplementary Tables 3 and 4.

Figure 4.. Results of modeling to predict the potential cost reduction associated with a shift of ACS care pathways.

(A-B) One-way sensitivity analysis for a hypothetical hospital that conducts 1,000 PCIs of each type of ACS. Results show the associated cost reductions when a given percentage of patients from the SFL pathway for STEMI (NFL for UA/NSTEMI) is converted to the candidate pathway. Per-patient hospitalization costs associated with each care pathway and adjusted for covariates mentioned in the legends to Figure 3 were obtained using 2-level hierarchical, mixed effects models. (C-D) Two-way sensitivity analyses. The proportion of the patients belonging to the SFS and SRS pathways for STEMI (NFS and NRS for UA/NSTEMI) was varied over a range of 30 – 70% and 0 – 20%, respectively. The resulting per patient costs were compared to the currently observed proportions (indicated using the colored circles). The results are shown as annual cost reduction in 2016 million US$. Hypothetical target of 70% SFS and 10% SRS groups is shown using color-coded stars.