Baisc Concept and Technique of FFR FuWai Hospital JieQian

Hemodynamic of Coronary Flow Special Stess Test in Cathlab Complementary to CTA

Physiology Of Coronary Flow

The Coronary Circulation-Anatomy Ao PaPaPaPa PvPvPvPv Collaterals Myocardium epicardial arterial vessels - myocardial microcirculation - venous component

Physics Law

Klocke, FJ, Measurement of Coronary Flow Reserve: Defining pathophysiology versus making decisions about patient care; Circulation: 1987; 76: pp The Coronary Circulation-Physiologic Regulation

CFR CFR ＝ Q s max /Q s rest Normal Vaulue Vary

Pathology of Coronary Flow

CFR :3 － 5 times ？ Is it specially to lesion? No ， Yew ， but no speciality rCFR(RFR)=Q s max /Q n’ max

R stenosis R myocardial FFR CFR CFR and rCFR: What Do They Investigate?

Hypothetical Case A ： 60 ％ DM B ： 80 ％ no DM CFR a maybe =CFR b ＝ 2 or 1.7

Interventional Carlogist Care What ？ If Intervention Ischemia Research

Better Criteria ？ Yes FFR ＝ Q s max /Q n max =P d /P a

Why Flow (Q) = Pressure

Coronary Stenosis Rheology Pressure-Flow Relationship Pressure drop across stenosis increases with flow in a non-linear fashion Entrance effects Separation losses Friction loss

FFR Definition

FRACTIONAL FLOW RESERVE: The index FFR (Fractional Flow Reserve) is based upon the two following principles: It is not resting flow, but maximum achievable flow which determines the functional capacity (exercise tolerance) of a patient At maximum vasodilation (corresponding with maximum hyperemia or with maximum exercise), blood flow to the myocardium is proportional to myocardial perfusion pressure ( ~ hyperemic distal coronary pressure)

Normal Value of Myocardial Fractional Flow Reserve Normal FFR = 1 PaPa P d FFR = PaPa P d

0.014” 3 cm Pressure Monitoring Guide Wires

Coronary Hyperemic Stimuli

PRACTICE OF CORONARY PRESSURE MEASUREMENT AND FFR （ 1 ） 1. Verification of equal signals when sensor at tip of the guiding catheter. Equalization if necessary 2. Advance wire, sensor crosses stenosis 3. Induce maximum hyperemia and measure FFR 4. Because sensor is 3 cm from tip, easily pull-back and push-up for exact spatial information. If desirable, perform pull-back recording

PRACTICE OF CORONARY PRESSURE MEASUREMENT AND FFR （ 2 ） 5. PCI if indicated, with possibility for Pw measurement for collateral flow assessment 6. Followed by FFR measurement to check result. If desired, perform hyperemic pull-back recording 7. verify absence of drift at the end of procedure, or between measurement in several vessels

LAD resting adenosine i.v.

pull-back across LAD plaque hyperemic pull-back recording

Aortic Pressure = 122 mm Hg Aortic Pressure = 89 mm Hg Coronary Pressure = 52 mm Hg Coronary Pressure = 40 mm Hg ΔP = 70 mmHG FFR = 52/122 = 0.43FFR = 40/89 = 0.45 Influence of Systemic Pressure on Transstenotic Gradient ΔP = 49 mmHG

1 Exercise Test Thallium Scan Dobut. echo True Positive Stress Tests Negative Stress Tests FFR and Non-Invasive Stress Testing in Lesions of Intermediate Severity Pijls NHJ, de Bruyne B, Peels K et al. New Engl J Med 1996

Ischemic Threshold Values of FFR AAAuuuttthhhooorrrsss RRReeefff PPPaaatttiiieeennntttsss ### TTTeeessstttTTThhhrrreeessshhhooolllddd De Bruyne et al.Circ VD60Bicycle ECG 0.72* Pijls et al.Circ VD pre+post PCI 60Bicycle ECG 0.74* Pijls&De BruyneNEJM VD, IntermediateSten 45Bicycle ECG +TL +Dobut Echo 0.75* Bartunek et al.JACC VD75Dobutamine Echo 0.78* Chamuleau et al.JACC 2000MVD127MIBI-Spect 0.74** Abe et al.Circ VD46Thallium 0.75* De Bruyne et alCirc 2001Post MI57MIBI-Spect * * 100 % Specificity; ** Optimal Cutoff Value 0.75

Hemodynamic of Coronary Flow Special Stess Test in Cathlab Complementary to CTA

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