Cost-effectiveness of an accelerated outpatient coronary CT angiography pathway in the emergency department setting at a tertiary cardiology centre

Abstract Background Emergency chest pain presentations represent a significant cost burden to the health service. Prior studies have shown the use of coronary computed tomography angiography (CCTA) in stable outpatients referred for invasive coronary angiography (ICA) to be safe and cost-effective. The HEART (History, Electrocardiogram, Age, Risk factors, Troponin) score is used to risk stratify patients with undifferentiated chest pain. Purpose We aimed to describe the cost benefit of an accelerated outpatient CCTA pathway compared with inpatient ICA for the investigation of patients presenting acutely to the emergency department (ED) with symptoms suggestive of coronary artery disease (CAD) at a tertiary referral centre. Given hospital length-of-stay is a known contributor to the cost of inpatient diagnostic work-up, we also aimed to investigate factors predicting wait time to ICA for those admitted for investigation. Methods We performed a cost analysis based on retrospective observational data including stable adult ED patients referred to the outpatient CCTA pathway (HEART score 0-3) or admitted for ICA (HEART score >3) at an Irish tertiary cardiology centre between January 1st and December 12th 2023. Patients with ST-elevation myocardial infarction were excluded. Multiple linear regression analysis was performed to identify predictors of wait time to ICA. Results 745 patients were included (Table 1). 369 patients (49.5%) underwent outpatient CCTA and 376 (50.5%) were admitted for ICA. The median time to outpatient CCTA was 14 days (IQR 5-24). There was an estimated saving of 78% per patient (€2990) through use of the CCTA pathway for the investigation of lower-risk individuals (Figure 1a), accounting for an annual saving of €1.1 million, with no increase in 30-day mortality or myocardial infarction. Patients referred for outpatient CCTA had a significantly shorter median hospital length-of-stay compared with those admitted for ICA [6.5 hours (IQR 5-9) vs 5 days (IQR 3-14.9), p