"FFRCT is in fact better than CTA alone in identifying lesions that are significant and that are flow limiting. The problem, of course, is that we don’t know about the costs," said Peter Block, MD, FACC.

In patients with suspected coronary artery disease (CAD), fractional flow reserve (FFR) calculated from coronary computed tomography angiography datasets (FFRCT) “demonstrated improved discriminative performance over coronary computed tomography angiography (CTA) and invasive coronary angiography (ICA) for diagnosis of patients and vessels with ischemia,” according to results from the HeartFlowNXT trial presented Oct. 30 as part of TCT 2013 in San Francisco and published simultaneously in the Journal of the American College of Cardiology.

The blinded, prospective multicenter trial looked at 254 patients with suspected CAD who were scheduled to undergo ICA. Results showed for FFRCT, the area under the receiver operating characteristic curve (95 percent CI) was 0.82 vs. 0.63 for coronary CTA (p<0.0001). Per-patient sensitivity and specificity were 86 percent and 79 percent for FFRCT vs. 94 percent and 33 percent for coronary CTA and 91 percent and 51 percent for ICA.

Additional Resources HeartFlowNXT Slides TCT 2013 Meeting Coverage

"Fractional flow reserve non-invasively calculated from coronary CTA data sets matches closely with invasively measured FFR and allows for identification of patients with hemodynamically significant coronary lesions with good accuracy," said lead investigator Bjarne L. Nørgaard, MD, PhD, from Aarhaus University Hospital in Denmark. "When compared to both coronary CTA and ICA, FFRCT led to a significant reduction in the proportion of false-positive results."

The authors add that moving forward, "the addition of FFRCT to coronary CTA may allow for a comprehensive anatomic and functional assessment of CAD in a manner potentially promoting beneficial clinical and cot outcomes, which remain to be definitively proven in appropriately designed prospective trials."

A separate trial – the ADVISE II trial – also presented Oct. 30 as part of TCT 2013 found “promising results” to assess the severity of CAD using instantaneous wave-free ratio (iFR).

The trial was a prospective, observational, non-randomized global multi-center registry study of 690 patients. Within the 69 percent of patients with associated iFR values in the iFR zone, 91.6 percent of stenosis were properly classified for hemodynamic severity. In addition, a hybrid iFR/FFR approach correctly classified 94.2 percent of coronary stenoses, with 65.1 percent of patients not needing adenosine administration.

"The results of the ADVISE II study support the use of iFR to simplify physiological guidance of percutaneous coronary intervention," said lead investigator Javier Escaned, MD, PhD, and interventional cardiologist from Hospital Clinico San Carlos in Madrid, Spain. "The promising results demonstrate the potential of boosting the benefits of ischemia-driven revascularization to a larger proportion of patients with CAD."

Keywords: Coronary Artery Disease, Sensitivity and Specificity, Constriction, Pathologic, Hemodynamics, Percutaneous Coronary Intervention, Registries, Coronary Angiography, Coronary Stenosis, San Francisco, Tomography, ROC Curve, United States

< Back to Listings