1. Emerging FFR Non-Wire-based Technology
Hector M. Garcia-Garcia MD,
MSc, PhD, FESC, FACC
MedStar Washington Hospital Center
Director, Angio and IVUS/NIRS corelab
Chairman, Clinical Event Committee

2. No disclosures

3. Functional Assessment of Coronary Stenosis Using
Angiography: will you treat it?
diameter stenosis (DS): 53%
Anatomy: DS = 53%
vs.
Physiology: FFR = 0.85
Quantitative Coronary Angiography (QCA)

4. Functional Assessment of Coronary Stenosis Using
Angiography: Background
Computer Tomography Methods
Echavarria-Pinto M, Garcia-Garcia HM et al. Interventional Cardiology. Oct 2015 ,Vol. 7, No. 5, 483
Gonzalvez PA, Garcia-Garcia HM et al. JACC: Cardiovascular Imaging. Vol. 8, No. 11, Nov 2015, 1322.

5. Functional Assessment of Coronary Stenosis Using
Angiography: Background
Traditional Methods
Issues
Invasive – need a wire
Need for adenosine:
Discomfort; Arrythmia
Time consuming
Pullback device not available
For bifurcations, wire in both main vessel and sidebranch
Expensive for patient/hospital
Worldwide acceptance 7-10%
Echavarria-Pinto M, Garcia-Garcia HM et al. Interventional Cardiology. Oct 2015 ,Vol. 7, No. 5, 483
Gonzalvez PA, Garcia-Garcia HM et al. JACC: Cardiovascular Imaging. Vol. 8, No. 11, Nov 2015, 1322.

6. Quantitative Flow Ratio (QFR)
Computed FFR based on two angiographic projections

7. Quantitative Flow Ratio - QFR: One-stop shop?

8. Quantitative Flow Ratio Relies on 3D QCA
3D vessel modelling is the backbone for the PCI procedure:
Allows the calculation of the functional significance parameter QFR
Optimal viewing angle for PCI
Precise stent sizing
Co-registration with OCT or IVUS

9. In-procedure time: < 5 min
Quantitative Flow Ratio - QFR (Quantitative Flow Ratio = Medis’ QCA derived FFR)
3D model reconstructed from 2 angiographic projections with angles ≥ 25º apart, acquired by monoplane or biplane systems. Patient-specific volumetric flow rate (at hyperaemia) calculated using the combination of contrast bolus front frame count and 3D QCA;
In-procedure time: < 5 min
QFR = 0.87
FFR = 0.85
Based on EuroPCR presentation by Aarhus University Hospital, Skejby, Denmark

10. Quantitative Flow Ratio Study Results – FAVOR I

11. Quantitative Flow Ratio Study Results
FFRQCA versus FFR FN FP
Difference: 0.00 ± (p = 0.541)
Tu et al. JACC Cardiovasc Interv 2014, 7:

12. Quantitative Flow Ratio Study Results – FAVOR II Pilot

13. Functional Assessment of Coronary Stenosis Using
Angiography: Background
1. fQFR: a fixed empiric hyperemic flow velocity (HFV) of 0.35 m/s that was derived from previous FFR studies was used for computation.
2. cQFR: frame count (FC) analysis was performed, without pharmacologically induced hyperemia, to derived the HFV.
3. aQFR: FC analysis was performed during hyperemia, induced by intravenous administration of adenosine or adenosine triphosphate. The “real” HFVs were derived and the software calculated 2 new QFR pullbacks.
Flow velocity is segment length in 3D QCA divided by dye flow time from FC.
Tu S et al. JACC: Cardiovascular Interventions. Vol 9, Issue 19, 10 Oct 2016,2024–2035 .

14. Functional Assessment of Coronary Stenosis Using
Angiography: Background
Tu S et al. JACC: Cardiovascular Interventions. Vol 9, Issue 19, 10 Oct 2016,2024–2035 .

15. QFR analysis in a dedicated offline software (Medis Suite XA)
Certified QFR analysis team
Vessel QFR = 0.54 Lesion QFR = 0.56
Note: The wire based FFR is 0.57

16. Functional Assessment of Coronary Stenosis Using
Angiography: Background
(A) Per patient (73) (B) Per vessel (84).
Tu S et al. JACC: Cardiovascular Interventions. Vol 9, Issue 19, 10 Oct 2016,2024–2035 .

17. Conclusions from Authors
Fast computation of FFR from coronary angiography (QFR), acquired with or without pharmacological hyperemia-induction, is feasible.
Contrast-flow QFR (cQFR) based on conventional diagnostic coronary angiography provides results similar to QFR based on hyperemic conditions, and is superior to fixed-flow QFR.
The favorable results of cQFR bears the potential of a wider adoption of FFR-based lesion assessment, as cQFR might reduce procedure time, risk, and costs (no need to use pressure wire, and no need to induce maximal hyperemia) .
The use of QFR is not without a stiff learning curve, which requires that users be certified by the offline software provider (Medis) before being able to start.
Current indications: Patients with stable angina;
Under investigations: MI, bifurcation lesions, lengthy diffuse disease, etc.

18. QFR Ongoing Studies FAVOR II study Q2FR trial ALL AMI trial
FDA IDE submission
ALL AMI trial

19. FFRangioTM
Data on file of CathWorks

20. FFRangioTM : Results From a Multicenter Validation Study
Data on file of CathWorks

21. Conclusions
Since these technologies are not interfering with the cath lab work flow, do not use any wire and do not require adenosine, they may become the new standard for evaluating coronary lesions.
Non-wire based FFR-like technologies have been validated and getting into prospective clinical trials.
They have the potential to increase awareness on which coronary lesions should be treated.