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Coronary stenting: the appropriate use of FFR. Morton J. Kern, MD Professor of Medicine Chief of Cardiology LBVA Associate Chief Cardiology University California Irvine Orange, California. To treat or not to treat?. Is this lesion producing Ischemia? Is PCI appropriate for situation?.
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Coronary stenting: the appropriate use of FFR Morton J. Kern, MD Professor of Medicine Chief of Cardiology LBVA Associate Chief Cardiology University California Irvine Orange, California
To treat or not to treat? Is this lesion producing Ischemia? Is PCI appropriate for situation?
The rationale for using coronary physiology is the inability of the 2D images of angiogram to accurately depict the 3D lesion characteristics limiting flow. 75% Dia 20% Dia
Intermediate Stenosis, no evidence ischemia Left Main Stenosis Multivessel CAD Serial Lesions Ostial and Branch Disease Uncertainty in Critical Angiographic Based Decisions
Measurement of FFR correlates to the results of stress testing and ischemia out of the lab. FFR is a ‘stress test’ for that artery in the lab at time of cath. Aortic, Pa FFR= Pd/Pa = 65/90 = 0.72 Coronary, Pd Resting pressures Adenosine
5 Steps to Accurate FFR • Zero guide and wire on table to atmosphere • Insert wire into guide and match wire/guide pressures in aorta • Cross lesion 2-3cm distal • Turn on IV adenosine 2-4 minutes • Confirm accuracy with pressure pull back
Rely on FFR Avoid pitfalls of pressure and FFR Technical • loose connections • Improper zero • Calibration offset Anatomic • Extreme tortuosity • Inability to wire vessel • Spasm Mechanical Wire/artery impact Pharmacologic • Inadequate hyperemia Hemodynamic Artifacts: • Damped pressure waveforms. • Guide obstruction • Contrast media • Very small guide (<5F) • Pressure signal drift • Side holes and ostial ‘pseudostenosis’
Rely on FFR – No Guide Catheter Side Holes or Damping From Nico Pijls
Rely on FFR – Avoid Signal Drift Drift Drift True Gradient Notch Notch No notch Notch
Severe stenosis filters high frequency components – No dichrotic notch Notch No notch Distal wave form is one key to drift
Q: Why can we not use IVUS/OCT for functional assessment? A: A single cross-sectional area does not mean the same thing everywhere. 5 < 4 mm² = significant stenosis ? Ref Diam (mm) 4 3 2 50 25 0 % Stenosis for an Cross Sectional Area of 4 mm²
Single anatomic parameters do not predict FFR with confidence IVUS v FFR
When can you NOT rely on FFR? • False Negative FFR • Pressure Damping • No hyperemia - wrong drug, not mixed • not delivered (IV?) or side holes • STEMI, culprit. STEMI – non-culprit OK • 4. LM + LAD when FFRepicardial <0.6 • 5. Serial lesion FFR of individual lesion (only gradient useful) • False Positive FFR • Technical errors (Pressure signal drift,zero, etc.)
Coronary Physiologic (FFR) Criteria and Clinical Outcome Studies
62 yo Man, RCA stent occl 2yr ago with return of CP LAD FFR=0.86, 0.87 Now 1V CAD and new approach
DEFER Study – 5 year data JACC 2007;49:2105
RW. 59 yo man with Angina, inferior perf defect 3V CAD – CABG vs PCI? FFR=0.71 2 Questions How Accurate is Stress Test? If PCI needed, FFR directed?
FAME study: Death and MI after 2 Years Tonino et al, NEJM 2009, Pijls et al, JACC 2010 Angio-guided FFR-guided P= 0.03 12.7 P= 0.03 % 9.5 10 8.4 6.1 5 Death or MI MI 2 year(exclusion of small periprocedural infarction) 0 2 year
Incremental Cost [$] FFR Guidance Improves Outcomes Incremental QALY FFR Guidance Saves Resources Economic Evaluation of FFR-guided PCI in pts with MVD. Fearon WF et al. Circ 2010;122:25450-2550 CABG ROTO DES BMS Balloon
Angiographic 3- or 2-Vessel Disease does NOT equal Physiologic 3- or 2V CAD FAME: Angiography vs FFR Tonino, P. A. L. et al. J Am Coll Cardiol 2010;55:2816-2821 3V CAD Angio = 14% physiol 2V CAD Angio= 43% physiol
FAME II – Ischemia directed PCI+OMT vs OMT alone Stable patients scheduled for 1, 2 or 3 vessel DES stenting FFR in all target lesions Registry Randomised Trial When all FFR >0.80 At least 1 stenosis with FFR ≤ 0.80 Randomisation 1:1 PCI + OMT OMT OMT 50% randomly assigned to FU Follow-up after 1, 6 months, 1, 2, 3, 4, and 5 years
FAME II Rate of Any Revascularisation 60 RCT:OMT vs. RCT:PCI+OMT = 12.1% vs. 1.7% HR (95% CI): 7.63 (3.24-18.0); logrank p<.0001 50 40 Cumulative incidence (%) 30 20 10 RCT:PCI+OMT vs. REGISTRY:OMT, p=0.54 0 0 1 2 3 4 5 6 7 8 9 10 12 Months after randomisation No. at risk RCT:OMT only 339 238 123 119 115 112 83 20 10 10 10 8 RCT:PCI+OMT 352 256 144 141 140 139 114 25 18 18 18 18 REGISTRY:OMT only 131 88 41 40 40 40 35 4 1 1 1 1
71 yo Man with typical angina, pos stress, CAD risk factorsWhat’s your best approach?
FFR CFX FFR CFX=0.88
LAD Xience 3.5x18. 2nd LAD lesion? All done? ? FFR = 0.68
Physiologic Guidance1. Appropriate need for Stents2. Objective info re ischemia3. Eliminates operator uncertainty
Chest pain, No objective evidence ischemia Asymptomatic Patients FFR FFR FFR FFR FFR FFR FFR FFR FFR FFR FFR FFR FFR
Revascularization Approaches per AUC 2v CAD with prox LAD 3v CAD Isolated LM LM and other CAD FFR reduces uncertainty and documents appropriateness
The Mandate for Physiologic Guidance arises from a decade of outcomes studies and is supported by guidelines Class IA Guidelines - ESC Class IIa Guidelines - ACC/ AHA/ SCAI