Background: The role of change in fractional flow reserve derived from CT (FFRCT) across coronary stenoses (Delta FFRCT) in guiding downstream testing in patients with stable coronary artery... Show moreBackground: The role of change in fractional flow reserve derived from CT (FFRCT) across coronary stenoses (Delta FFRCT) in guiding downstream testing in patients with stable coronary artery disease (CAD) is unknown. Objectives: To investigate the incremental value of Delta FFRCT in predicting early revascularization and improving efficiency of catheter laboratory utilization. Materials: Patients with CAD on coronary CT angiography (CCTA) were enrolled in an international multicenter registry. Stenosis severity was assessed as per CAD-Reporting and Data System (CAD-RADS), and lesion-specific FFRCT was measured 2 cm distal to stenosis. Delta FFRCT was manually measured as the difference of FFRCT across visible stenosis. Results: Of 4730 patients (66 +/- 10 years; 34% female), 42.7% underwent ICA and 24.7% underwent early revascularization. AFFRCT remained an independent predictor for early revascularization (odds ratio per 0.05 increase [95% confidence interval], 1.31 [1.26-1.35]; p < 0.001) after adjusting for risk factors, stenosis features, and lesion-specific FFRCT. Among the 3 models (model 1: risk factors + stenosis type and location + CAD-RADS; model 2: model 1 + FFRCT; model 3: model 2 + AFFRCT), model 3 improved discrimination compared to model 2 (area under the curve, 0.87 [0.86-0.88] vs 0.85 [0.84-0.86]; p < 0.001), with the greatest incremental value for FFRCT 0.71-0.80. AFFRCT of 0.13 was the optimal cut-off as determined by the Youden index. In patients with CAD-RADS >3 and lesion-specific FFRCT <0.8, a diagnostic strategy incorporating AFFRCT >0.13, would potentially reduce ICA by 32.2% (1638-1110, p < 0.001) and improve the revascularization to ICA ratio from 65.2% to 73.1%. Conclusions: AFFRCT improves the discrimination of patients who underwent early revascularization compared to a standard diagnostic strategy of CCTA with FFRCT, particularly for those with FFRCT 0.71-0.80. AFFRCT has the potential to aid decision-making for ICA referral and improve efficiency of catheter laboratory utilization. Show less
Background: The ADVANCE registry is a large prospective study of outcomes and resource utilization in patients undergoing coronary computed tomography angiography (CCTA) and CT-based fractional... Show moreBackground: The ADVANCE registry is a large prospective study of outcomes and resource utilization in patients undergoing coronary computed tomography angiography (CCTA) and CT-based fractional flow reserve (FFRCT). As experience with new technologies and practices develops over time, we investigated temporal changes in the use of FERCT within the ADVANCE registry.Methods: 5083 patients with coronary artery disease (CAD) on CCTA were prospectively enrolled in the ADVANCE registry and were divided into 3 equally sized cohorts based on the temporal order of enrollment per site. Demographics, CCTA and FERCT findings, and clinical outcomes through 1-year follow-up, were recorded and compared between tertiles.Results: The number of patients with a >= 70% stenosis on CCTA was similar over time (33.6%, 30.9%, and 33.8% for cohort 1-3). The rate of positive FFRCT <= 0.80 was higher for cohorts 2 (67.3%) and 3 (74.6%) than for cohort 1 (57.1%, p < 0.001). Invasive FFR rates decreased from 25.8% to 22.4% between cohort 1 and 3 (p = 0.023). Moreover, patients with a FFRCT <= 0.80 were less frequently referred for invasive coronary angiography (ICA) (from 62.9% to 52.9%, p < 0.001), and underwent fewer revascularizations between cohort 1 and 3 (from 41.9% to 32.0%, p < 0.001). The prevalence of major events was low (1.2%) and similar between cohorts.Conclusions: Growing experience with FFRCT improved the likelihood of identifying hemodynamically significant CAD and safely reduced the need for ICA and revascularization in patients with anatomically significant disease even in the instance of an abnormal FFRCT. Show less
