Use of CMR LVEF measurement for the Prediction of the Cost of Heart Failure Care (RF_SA_440)

Heart failure (HF) is a leading cause of morbidity and mortality in the United States and is projected to increase in the next decade.¹ Left ventricular ejection fraction (LVEF) is currently one of the most widely used imaging parameters to guide clinical management. Currently, the most common imaging modalities used to obtain LVEF measurements include transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR). In clinical practice, CMR is not typically the first imaging modality selected to obtain LVEF measurements due to concerns related to cost, study duration, accessibility, and incompatibility. However, it is considered the gold standard for deriving LVEF measurements due to its precision and ability to provide additional valuable information including tissue characterization. Given the importance of LVEF in clinical decision-making, an accurate assessment is required to follow guideline directed recommendations. Our study aims to evaluate the role of CMR derived LVEF in the prediction of HF cost of care.

Methods:

A retrospective single-center cohort study of 420 participants >18 years of age with CMR images from 2009-2019 with known or suspected HF. Median follow-up time was 4 years. The primary outcome of interest was a composite including HF admission, left ventricular assist device (LVAD), cardiovascular disease-related death, heart transplantation, and implantable cardioverter defibrillator (ICD) implantation. Risk groups were defined as low (LVEF >50% without history of HF), intermediate (LVEF 35-50% or LVEF >50% with history of HF), and high risk (LVEF < 35%) for developing an adverse cardiac event. Imaging and procedural costs were based on Centers for Medicare and Medicaid Services (CMS) reimbursement standards by current procedural terminology (CPT) codes.^2-6 Medication costs, HF admission, and management of HF patients (unstable and stable) were obtained from previously published literature.^7-11  Per person costs were calculated by taking the total cost of HF care (admission, medications, device, imaging, and management) and dividing by the number of individuals stratified into each risk group. Costs were adjusted to 2022 US$.¹² One-way ANOVA and Tukey multiple comparisons test were used to determine significance among risk groups.

Results:

417 participants were included (3 individuals were missing HF outcome data) with a mean age of 49±17 years, 47.7% men, 41.4% Black, and 49.8% White. Our cohort identified 239 low, 105 intermediate, and 73 high-risk participants using CMR-LVEF measurements. Average LVEF (%) was 39.1±17.4% and 55.3±11.0% (p: < 0.0001) for those with and without HF-related events. The per-person cost (2022$) of managing individuals with HF outcomes incrementally increased as the risk for developing HF-related events increased (range $31,407.31 to $52,883.79) (p: < 0.0001) (Fig 1, Table 1). Tukey multiple comparisons test of per-person costs were significant between each group, p: < 0.0001, showing that risk-stratification based on LVEF is predictive of HF-related events and their associated costs. (Fig 1, Table 1).

Conclusion:

CMR-LVEF measurements may improve prediction of HF costs by correctly risk stratifying individuals enabling appropriate guideline-based therapies. Although our cohort is skewed towards low-risk patients who are less likely to be hospitalized and incur greater costs, this study provides insights into real-world implications of HF management costs associated with patients at different risk levels.