Three 'fast facts' about FFRCT

The ability to make more accurate diagnoses while minimizing invasiveness, cost and patient risk is an important objective in all aspects of cardiology.

Fractional Flow Reserve computed from CT angiography (FFRCT, Heartflow) offers a noninvasive approach for evaluating the hemodynamic severity of coronary lesions. By imaging and calculating the potential for a lesion to cause ischemia, cardiologists may avoid costly — and potentially unnecessary — invasive coronary angiography.

Recent studies have indicated that FFRCT offers diagnostic accuracy that is superior to standard coronary angiography. Moreover, some clinicians believe that the widespread uptake of FFRCT would likely reduce the number of patients referred for revascularization on the basis of lesions that prove to be functionally insignificant.

Researchers are also considering potential uses of this technology for various other types of medical imaging, according to J. Jeffrey Carr, MD, of Wake Forest University School of Medicine.

“These approaches can be applied to many aspects of medical imaging, and we are seeing just the beginning,” Carr said.

Cardiology Today compiled a list of five essential things to know about this new imaging modality.

1. In the DeFACTO study, FFRCT did not meet its primary endpoint, but outperformed CT alone.

In the DeFACTO study, FFRCT exhibited improved accuracy over CT in detecting coronary lesions with hemodynamically significant stenosis. Its diagnostic accuracy was 73%, which did not fulfill the primary endpoint for accuracy; however, CT alone had a diagnostic accuracy of 64% for lesions with stenosis of 50% or greater, and FFRCT was also superior to CT in per-patient specificity and sensitivity. Read more

2. DISCOVER-FLOW showed superior diagnostic accuracy and fewer false positives with FFRCT.

A second noteworthy study of FFRCT, DISCOVER-FLOW, found that FFRCT yielded “superior and additive” diagnostic accuracy over evaluation by coronary CTA. The study was smaller than DEFACTO, and assessed accuracy only on a per-vessel level. However, a notable finding of DISCOVER-FLOW was that FFRCT yielded a much lower rate of false positives than coronary CTA. Read more

3. In the multicenter NXT trial, FFRCT demonstrated per-patient specificity of 86%.

Results from the multicenter NXT trial, which evaluated FFRCT in patients with suspected stable CAD, indicated that FFRCT had in a per-patient sensitivity of 86% (95% CI, 77%-92%) and a specificity of 79% (72%-84%) for identifying myocardial ischemia. In a related editorial, Harvey S. Hecht, MD, of the Icahn School of Medicine at Mount Sinai, wrote that widespread acceptance of FFRCT would be a “major game-changer.” Read more