Addition of FFR-CT data leads to management changes for stable angina

When CT-derived fractional flow reserve data were added to CT angiography data, interventional cardiologists changed their recommendations for management of patients with stable angina more than one-third of the time, according to findings of the FFR-CT RIPCORD study presented at EuroPCR.

Previous research demonstrated that invasive FFR-directed PCI is associated with better outcomes than angiography-directed PCI because of better detection of a lesion’s significance, according to the study background. The RIPCORD study found that when invasive FFR data were available for patients with stable angina, management was altered in 26% of cases compared with angiographic assessment alone.

Nick Curzen, BM, PhD, FRCP, from University Hospital Southampton and faculty of medicine, University of Southampton, United Kingdom, and colleagues conducted the FFR-CT RIPCORD study to determine whether data from FFR-CTwould similarly affect the management of patients with stable angina. Curzen and colleagues hypothesized that availability of FFR-CT (HeartFlow) would lead to a substantial change in the interpretation of lesion-specific significance, and that it would lead to a change in management similar to that seen in RIPCORD.

Three experienced interventional cardiologists reviewed 200 consecutive patients with stable angina who were recruited into the NXT study of FFR-CT. For each patient, they reviewed a CT angiogram, determined which vessels had significant stenosis and decided on one of four management plans: optimal medical therapy, optimal medical therapy plus PCI, optimal medical therapy plus CABG, or more information required (ie, invasive FFR needed). The three-member panel then reviewed FFR-CT data for each patient, described anew which vessels were significant and determined a second management plan based on those data.

The primary endpoint was the difference between management based on interpretation of the CT angiogram alone vs. management incorporating FFR-CT data.

There was a change in management in 36% of cases after FFR-CT data were analyzed.

Optimal medical therapy alone was selected 33.5% of the time based on CT angiography alone and 56.5% of the time based on CT angiography plus FFR-CT data (percent change, 23%).
Optimal medical therapy plus PCI was selected 43.5% of the time based on based on CT angiography alone and 39% of the time based on CT angiography plus FFR-CT data (percent change, –5%).
Optimal medical therapy plus CABG was selected 4% of the time based on based on CT angiography alone and 4.5% of the time based on CT angiography plus FFR-CT data (percent change, 0.5%).
More information required was selected 19% of the time based on based on CT angiography alone and 0% of the time based on CT angiography plus FFR-CT data (P < .001 by chi-square test).

Forty-four percent of patients had decisions altered after physicians incorporated FFR-CT data, and 8% of patients (18% of those recommended for PCI after CT angiography alone) had a change in vessel assigned to PCI after FFR-CT data were analyzed.

“These results are consistent with those of the invasive RIPCORD study,” Curzen said during a presentation. “If this novel proof-of-concept result can be confirmed in large-scale trials, this suggests that noninvasive FFR-CTcan be used as a clinically relevant tool that mimics the well-described ability of invasive FFR to refine management decisions for patients with chest pain that are made based on [invasive angiography] alone. This would have important implications for clinical practice.” – by Erik Swain

Reference:

Curzen N, et al. Hot Line: Coronary Physiology and Imaging. Presented at: EuroPCR; May 19-22, 2015; Paris.

Disclosures: The study was funded by an unrestricted research grant from HeartFlow. Curzen reports receiving honoraria from HeartFlow, St. Jude Medical and Volcano and institutional grant/research support from Boston Scientific, Haemonetics, HeartFlow and Medtronic.