Imaging update: CT-FFR is safe and feasible for patients with severe aortic stenosis

CT-derived fractional flow reserve (CT-FFR) is a safe, feasible treatment option for patients with severe aortic stenosis, according to a new study published in Circulation: Cardiovascular Interventions. The findings suggest potential improvements in the treatment of patients undergoing transcatheter aortic valve replacement (TAVR).

The authors explored data from a single facility in Australia from November 2018 to November 2019. The final cohort included 39 patients and 60 vessels. The mean patient age was 76.2 years old.

Overall, on a per-vessel basis, the team observed a “strong positive correlation” between fractional flow reserve and CT-FFR. CT-FFR achieved an overall diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 76.7%, 73.9%, 78.4%, 68% and 82.9%, respectively. Its area under the ROC curve was 0.83, higher than either coronary computed tomography angiography or quantitative coronary angiography.

On a per-patient basis, meanwhile, the overall diagnostic accuracy, sensitivity, specificity, PPV and NPV were 76.9%, 76.5%, 77.3%, 72.2% and 81%, respectively. The area under the ROC curve was 0.81.

“These preliminary data suggest that the diagnostic accuracy of CT-FFR potentially enables its use in clinical practice,” wrote lead author Michael Michail, PhD, of Monash University in Melbourne, Australia, and colleagues.

The team did note that its work had certain limitations, including the fact that it only included data from a single facility. Also, they added, “our cohort represents a younger age group than those currently undergoing TAVR, and it is unclear whether these results can be extrapolated into very elderly patients.”

“Further research is required to assess the clinical utility of CT-FFR and outcomes in this patient cohort,” the authors wrote. “With further validation, this may reduce the need for invasive coronary angiography in pre-TAVR assessment.”

The full analysis can be read here.