Practical Tips on FFR (Fractional Flow Reserve) Head, Department of Cardiology Director of Cardiac Catheterization Labororatory, Director of Medical Informatics, National Heart Centre Singapore 10/2012 FFR Practical Tip Easier Set-Up • Wireless integration with hemodynamic system • Automatic wire zeroing and calibration • Plus-and-play • Can work with any hemodynamic system FFR Practical Tip • Borderline lesion • Multi-vessel disease • Ostial lesion FFR-Guided PCI performed on indicated lesions only if FFR 90% narrowed are significant by FFR 65% 20% 20% 4% 35% P. Tonino, et al, J Am Coll Cardiol 2010;55:2816–21 Pre Stent Post Stent FU @ 8 mo Courtesy of Chang-Wook Nam, MD Jailed Side Branches and FFR FFR in 97 “Jailed” Side Branches 53/73 (73%) of all lesions > 75% stenosis 0.75 At 10 month F/U no Death, MI, or Sidebranch TLR Koo et al. J Am Coll Cardiol 2005;46:633-7. FFR Practical Tip Too big  pressure wedging when engaging coronary Too small  dampens the aortic signal Impact of Catheter Size on Hyperemic Flow Beware of pressure damping De Bruyne et al. Cathet Cardiovasc Diagn 1994;33:145-152. Using diagnostic catheter more friction with guidewire smaller inner lumen  pressure transmission may be dampened in case of wire causing coronary dissection  will need to exchange for guiding catheter to perform emergency PCI Effect of Using catheter with sideholes Pressure recorded by the guide cath (Pa) is influenced by coronary pressure via guide lumen and aortic pressure via side-holes. Pa may be lower than the value recorded by the guide catheter leading to a false –ve FFR. FFR Practical Tip Sensor just outside tip of guiding catheter TCT 24.09.09 Damped pressure ** ensure adequate flushing. 1 2 Causes - large guide, small vessel, ostial disease. Solution - Disengage the guide catheter during the FFR measurement. DO NOT use an IC (intra-coronary) hyperaemic stimulus. TCT 24.09.09 TCT 24.09.09 FFR Practical Tip True Gradient Drift  When a true gradient is present the distal pressure is “ventricularised”.  When the difference is due to pressure drift,  the two tracings have similar shape.  Aortic notch inCathet distal Cardiovasc curve (+) Intervent 2000;49:1-16 Adapted from Pijls et al.  If drift is suspected “re-equalisation” is necessary.  When a true gradient is present the distal pressure is “ventricularised”.  When the difference is due to pressure drift,  the two tracings have similar shape.  Aortic notch in distal curve (+) TCT 24.09.09 Sensor (Pd) Tip of Catheter (Pa) FFR Practical Tip  Check whether patient has asthma / bronchospasm  Ask about coffee consumption  Administer IC GTN   coronary spasm IC Adenosine IV adenosine IC Papaverine Peak effect 10 s < 2 min 10 – 30 s Duration of effect 20 s Persists till < 2 min after D/C 45 – 60 s Dose 40 – 60 mcg LCA; 20 – 40 mcg RCA 140 mcg/kg/min; higher dose if given peripherally 16 – 20 mg LCA 12 – 16 mg RCA Side effects AV block AV block Bronchospasm Chest pain  BP;  HR QTc; Steady-state hyperemia; Pull-back curve Bolus; Rapid Pullback curve Central vein; Infusion pump; Time consuming Torsades / VT / VF; Wait 5 min between measurements; < 3 doses Main advantages Easy, rapid Main No pullback curve. disadvantages Do not use guide / Precautions with side-holes. Torsade de pointes / VT / VF Intravenous Adenosine Steady State: Maximum Hyperemia Horizontal Pd/Pa line: Steady State and likely Maximum Hyperemia 1 2 3 4 IV adenosine 4 3 1 2 Intracoronary Adenosine (bolus) Sub-Maximal Hyperemia Fluctuating Pd/Pa line: Steady State not achieved and likely Sub-Maximal Hyperemia Intracoronary vs. Intravenous Adenosine Higher IC Doses Produce More Hyperemia IC Adenosine Casella et al, Am Heart J 2004 46 pts Intermediate lesions Increasing doses of adenosine for FFR: • 60 mcg • 120 mcg • 180 mcg • 360 mcg • 720 mcg (JACC Intv 2011; 4: 1079-84) Intracoronary Papaverine Steady-State Hyperemia Similar effect as IV adenosine Pijls N, De Bruyne B. Coronary Pressure 2nd Edition, Springer 2000 More ideal hyperemic agent:     Adenosine – non-selective; very short-acting Regadenoson  advantages: more A2A selective IV single bolus (0.4 mg) over 10 sec short, but slightly longer duration of action (2-4 min) comparable efficacy fewer side-effect  FDA approval 2008 JACC Intv 2011;4:1085-92 25 pts with intermediate coronary stenoses FFR assessed using: o IV adenosine 140 mcg/kg/min o IV regadenoson 400 mcg bolus IC Adenosine Infusion 240 µg / min FFR Practical Tip Analyser selects flush point Actual FFR is 0.83 If the PW sensor hits the coronary wall, “spikes” appear in the waveform. Solution – pull back or advance the wire 2-3 mm. Checklists •Infusion pump; connection •IV infusion vs IC bolus •Introducer in place •Check the cursor position •Check the shape of pressure curve •Guide catheter problem Side hole Flush Disengage during recording •Drift •Spasm / accordion effect Marina Bay Sands Expo and Convention Centre  ... integration with hemodynamic system • Automatic wire zeroing and calibration • Plus-and-play • Can work with any hemodynamic system FFR Practical Tip • Borderline lesion • Multi-vessel disease... all indicated lesions were measured by FFR (N=1329) Almost all stenoses >90% narrowed are significant by FFR 65% 20% 20% 4% 35% P Tonino, et al, J Am Coll Cardiol 2010;55:2816–21 Pre Stent Post