CT Angiography-derived fractional flow reserve in the emergency department: Insights from a matched cohort analysis

The feasibility of CT angiography (CTA)-based fractional flow reserve (CT-FFR) has been documented in acute chest pain (ACP). The present study aimed to evaluate the impact of CT-FFR on clinical outcomes and costs in the emergency department (ED).

ACP patients with intermediate (30 - 90 %) stenosis on coronary or triple rule-out CTA were prospectively enrolled. Treatment decisions were made once the off-site CT-FFR results were available. ED length of stay (LOS), downstream test utilization (stress echocardiography, single-photon emission CT, invasive coronary angiography [ICA]), and revascularization efficiency (percutaneous coronary interventions per ICAs) were documented. Costs of care were collected for a 90-day period. The prospective cohort was compared to a control group without CT-FFR analysis matched for sex, age, and Coronary Artery Disease-Reporting and Data System category.

A total of 100 patients (age: 66.2 ± 10.2 years) were enrolled and matched to 100 retrospective patients (age: 67.8 ± 10.6 years), with 39.0 % women in both groups. LOS was higher in the CT-FFR group (9.0 [6.0 - 28.0] vs. 8.0 [6.0 - 12.0] hours, p = 0.02), without differences in the rate of downstream test utilization (all p > 0.05). CT-FFR led to a higher revascularization efficiency (32.5 % [13/40] vs. 12.2 % [5/41]; p = 0.03). CT-FFR resulted in an increase in aggregate expenditures (2069.0 [1757.0 - 5135.0] vs. 879.0 [306.0 - 3684.0] $, p < 0.001) after 90 days.

While the utilization of CT-FFR in ACP does increase ED LOS and associated healthcare costs, the selection of patients who may benefit from subsequent ICA may prove more efficacious.

ACP, acute chest pain; CAD-RADS, Coronary Artery Disease-Reporting and Data System; CCTA, coronary CT angiography; CTA, CT angiography; CT-FFR, coronary CT angiography-derived fractional flow reserve; ED, emergency department; ICA, invasive coronary angiography; LOS, length of stay; PCI, percutaneous coronary intervention; SPECT, single-photon emission CT; TRO, triple rule-out.