Cost savings for pVAD compared to ECMO in the management of acute myocardial infarction complicated by cardiogenic shock: An episode-of-care analysis.

BACKGROUND

Acute myocardial infarction complicated by cardiogenic shock (AMICS) occurs in up to 10% of acute myocardial infarction admissions and is associated with high mortality, frequent adverse outcomes, prolonged hospitalizations, extensive medical resource utilization, and major cost. Using hospital cost data for Medicare Fee-for-Service (FFS) patients with AMICS, we sought to evaluate in hospital and 45-day outcomes and cost, comparing patients treated with percutaneous ventricular assist device (pVAD) versus extracorporeal membrane oxygenation (ECMO). The goal of this study was to better understand clinical and economic outcomes of AMICS to help clinicians and hospitals optimize outcomes most economically for AMICS patients.

METHODS

A retrospective claims analysis identified patients from the full census Medicare Standard Analytic Files compiled by the Center for Medicare and Medicaid (CMS) including: Inpatient, Outpatient, Skilled Nursing Facility and Home Health files for Medicare FFS beneficiaries. Study costs were defined as the total costs incurred by providers for treating a population with AMICS. Medicare FFS beneficiaries who experienced an inpatient admission during the index period (January 1, 2015 to March 31, 2017) with a diagnosis of AMICS were eligible for study inclusion and were identified by the presence of appropriate International Classification of Diseases, Ninth and Tenth Versions (ICD-9 and ICD-10) diagnosis and procedure codes. To create a matched sample and control for any baseline differences, a 1:1 Propensity Score Matching (PSM) was performed based on criteria such as age, gender, race, geographic distribution, and 11 high-cost comorbidities (e.g., congestive HF, coronary artery disease, diabetes, etc.). Index length of stay (LOS), index costs, discharge disposition (including mortality), post-index utilization, and episode-of-care (EOC) costs were reviewed. EOC was defined as index admission for all patients plus a 45-day post index period for patients who survived the index admission.

RESULTS

Each cohort included 338 patients. Index in-hospital mortality rates were 53% for pVAD versus 64% for ECMO (178 vs. 217; p = .0023), and total EOC in-hospital mortality rates were 66% for pVAD versus 74% for ECMO (222 vs. 250; p = .0160). Index LOS for pVAD was 27% lower versus ECMO (12.12 vs. 16.59; p = .0006). The index LOS for patients discharged alive was 25% lower for pVAD versus ECMO (17.73 vs. 23.62; p = .0016). For patients that experienced in-hospital mortality during their index stay, pVAD had a 44% lower LOS compared to ECMO (7.08 vs. 12.66; p < .0001). Following index hospitalization, the average cost savings with additional inpatient care was 31% lower for pVAD patients ($62,188 vs. $90,087; p = NS). During the EOC, pVAD patients incurred 32% lower costs compared to ECMO patients ($117,849 vs. $172,420; <.0001).

CONCLUSIONS

This study of Medicare FFS patients demonstrates that hospitals utilizing pVAD for appropriately selected AMICS patients have reduced mortality rates and reduced index LOS with lower index facility costs and lower post index 45-day costs. The study results offer hospitals and clinicians an opportunity to improve clinical outcomes and reduce total EOC costs in treating patients with AMI complicated by CS.