Real world hospital costs following stress echocardiography in the UK: a costing study from the EVAREST/BSE-NSTEP multi-entre study

Background: Stress echocardiography is widely used to detect coronary artery disease, but little evidence on downstream hospital costs in real-world practice is available. We examined how stress echocardiography accuracy and downstream hospital costs vary across NHS hospitals and identifed key factors that afect costs to help inform future clinical planning and guidelines. Methods: Data on 7636 patients recruited from 31 NHS hospitals within the UK between 2014 and 2020 as part of EVAREST/BSE-NSTEP clinical study, were used. Data included all diagnostic tests, procedures, and hospital admissions for 12 months after a stress echocardiogram and were costed using the NHS national unit costs. A decision tree was built to illustrate the clinical pathway and estimate average downstream hospital costs. Multi-level regression analysis was performed to identify variation in accuracy and costs at both patient, procedural, and hospital level. Linear regression and extrapolation were used to estimate annual hospital cost-savings associated with increasing predictive accuracy at hospital and national level. Results: Stress echocardiography accuracy varied with patient, hospital and operator characteristics. Hypertension, presence of wall motion abnormalities and higher number of hospital cardiology outpatient attendances annually reduced accuracy, adjusted odds ratio of 0.78 (95% CI 0.65 to 0.93), 0.27 (95% CI 0.15 to 0.48), 0.99 (95% CI 0.98 to 0.99) respectively, whereas a prior myocardial infarction, angiotensin receptor blocker medication, and greater operator experience increased accuracy, adjusted odds ratio of 1.77 (95% CI 1.34 to 2.33), 1.64 (95% CI 1.22 to 2.22), and 1.06 (95% CI 1.02 to 1.09) respectively. Average downstream costs were £646 per patient (SD 1796) with signifcant variation across hospitals. The average downstream costs between the 31 hospitals varied from £384–1730 per patient. False positive and false negative tests were associated with average downstream costs of £1446 (SD £601) and £4192 (SD 3332) respectively, driven by increased non-elective hospital admissions, adjusted odds ratio 2.48 (95% CI 1.08 to 5.66), 21.06 (95% CI 10.41 to 42.59) respectively. We estimated that an increase in accuracy by 1 percentage point could save the NHS in the UK £3.2 million annually. Conclusion: This study provides real-world evidence of downstream costs associated with stress echocardiography practice in the UK and estimates how improvements in accuracy could impact healthcare expenditure in the NHS. A real-world downstream costing approach could be adopted more widely in evaluation of imaging tests and interventions to refect actual value for money and support realistic planning

Standardized Delineation of Endocardial Boundaries in Three-Dimensional Left Ventricular Echocardiograms

International audienceBackground: Three-dimensional (3D) echocardiography is fundamental for left ventricular (LV) assessment. The aim of this study was to determine discrepancies in 3D LV endocardial tracings and suggest tracing guidance.Methods: Forty-five 3D LV echocardiographic data sets were traced by three experienced operators, from different centers, according to predefined guidelines. The 3D meshes were compared with one another, and the endocardial areas of discrepancies were identified. A discussion and retracing protocol was used to reduce discrepancies. For each data set, an average 3D mesh was produced (reference mesh). Subsequently, four novice operators, divided into two groups, traced 20 of the data sets. Two operators followed the tracing protocol and two did not.Results: The intraclass correlation coefficients among the three experienced operators for end-diastolic volume, end-systolic volume, and ejection fraction were 0.952, 0.955, and 0.932. The absolute distances between tracings were 1.11 ± 0.45 mm. The highest tracing discrepancies were at the apical cap and anterior and anterolateral walls in end-diastole and end-systole and also at the basal anteroseptum in end-systole. Agreement with the reference meshes was better for the novice operators who followed the guidance (10.9 ± 17.3 mL, 10.2 ± 14.7 mL, and −2.2 ± 4.1% for end-diastolic volume, end-systolic volume, and ejection fraction) compared with those who did not (16.3 ± 16.4 mL, 17.0 ± 16.0 mL, and −4.2 ± 4.1%, respectively).Conclusions: Comparing 3D LV tracings, the endocardial areas that are the most difficult to delineate were identified. The suggested protocol for LV tracing resulted in very good agreement among operators. The reference 3D meshes are available for online testing and ranking of LV tracing algorithms