Incidence and predictors of lesion-specific ischemia by FFRCT: Learnings from the international ADVANCE registry.
J Cardiovasc Comput Tomogr. 2018 Mar - Apr;12(2):95-100. doi: 10.1016/j.jcct.2018.01.008. Epub 2018 Feb 2. Kitabata H1, Leipsic J2, Patel MR3, Nieman K4, De Bruyne B5, Rogers C6, Pontone G7, Nørgaard BL8, Bax JJ9, Raff G10, Chinnaiyan KM10, Rabbat M11, Rønnow Sand NP12, Blanke P13, Fairbairn TA14, Matsuo H15, Amano T16, Kawasaki T17, Morino Y18, Akasaka T1.
BACKGROUND: To date, the clinical utility of coronary computed tomography angiography (CTA)-derived fractional flow reserve (FFRCT) has been limited to trials and single center experiences. We herein report the incidence of abnormal FFRCT (≤0.80) and the relationship of lesion-specific ischemia to subject demographics, symptoms, and degree of stenosis in the multicenter, prospective ADVANCE registry.
METHODS: One thousand patients with suspected angina having documented coronary artery disease on coronary CTA and clinically referred for FFRCT were prospectively enrolled in the registry. Patient demographics, symptom status, coronary CTA and FFRCT findings were recorded. Univariate and multivariate analyses were performed to investigate the predictors related to abnormal FFRCT.
RESULTS: FFRCT data were analyzed in 952 patients (95.2%). Overall, 51.1% patients had a positive FFRCT value (≤0.80). Patients with ≥3 risk factors had a significantly higher rate of abnormal FFRCT than those with <3 risk factors (60.2% vs. 43.9%, p = 0.0001). On multivariate analysis, baseline diabetes (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.04-2.21, p = 0.030) and hypertension (OR 1.56, 95%CI 1.14-2.14, p = 0.005) were both predictive of abnormal FFRCT. In addition, >70% stenosis was significantly associated with low FFRCT (OR 31.16, 95%CI 12.25-79.22, p < 0.0001) vs. <30% stenosis. Notably, stenosis 30-49% vs. <30% had an increased likelihood of ischemia (OR 3.74, 95%CI 1.52-9.17, p < 0.0001).
CONCLUSIONS: In this real-world registry, CT angiographic stenosis severity in addition to baseline cardiovascular risk factors conferred an increased likelihood of an abnormal FFRCT. Importantly, however, mild CT angiographic stenoses were noted to have an increased hazard for ischemia and the converse holding true for more severe stenoses as well.