Pressure Wire Evaluation of Pressure Wire Evaluation of the Left Main Stemthe Left Main Stem

Dr Phil MacCarthyDr Phil MacCarthy

Consultant CardiologistConsultant Cardiologist

King’s Cardiac CentreKing’s Cardiac Centre

Left Main 5+ at AA2007, Jan 24th, 2007.

No conflicts of interestNo conflicts of interest

Assessment of critical LMS Assessment of critical LMS disease is sometimes easy…disease is sometimes easy…

A more common clinical A more common clinical scenarioscenario

How do you currently establish the

haemodynamic importance of a LMS

lesion?Surgery!

The stakes are high…The stakes are high…

The angiogram is a 2D The angiogram is a 2D representation of a complex 3D representation of a complex 3D

structurestructure

Topol and Nissen, Circulation 1995

Correlation between LMS Correlation between LMS anatomy and physiologyanatomy and physiology

Jasti et al, Circulation 2004

Studies of LMS FFR vs Studies of LMS FFR vs OutcomeOutcome

ReferenceReference nn FFR<0.FFR<0.7575

FFR>0.FFR>0.7575

(Deferr(Deferred)ed)

F/UF/U(mont(mont

hs)hs)

MortalitMortality in y in

deferredeferred groupd group

Bech et alBech et al Heart 2001Heart 2001 5454 3030 2424 2929 00

Jimenez-Jimenez-Navarro et Navarro et

alal

J Inv CardiolJ Inv Cardiol20042004

2727 77 2020 2626 00

Jasti et alJasti et al CirculationCirculation20042004

5555 1414 4141 3838 3 (all 3 (all non-non-

cardiac)cardiac)

Suemaru Suemaru et alet al

Heart Heart VesselsVessels20052005

1515 77 88 32.532.5 00

Legutko et Legutko et alal

Kardiol PolKardiol Pol20052005

3838 1818 2020 2424 00

Lindstaedt Lindstaedt et alet al

Am Heart JAm Heart J20062006

5151 2727 2424 2929 00

54 patients with equivocal LMS stenosis – FFR>0.75 in 24 (medical), FFR<0.75in 30 (CABG)

Bech et al Heart 2001; 86: 547

Jasti et al, Circulation 2004

51 patients – 24 FFR>0.75 treated medically, 27 FFR<0.75 treated surgically

Lindstaedt et al, Am Heart J 2006; 152: 156

Left main disease in the Left main disease in the stable patientstable patient

Case 1 - StableCase 1 - Stable

Case 1 - StableCase 1 - Stable

Case 2 - StableCase 2 - Stable

Case 2 - StableCase 2 - Stable

Pressure-wire study LMSPressure-wire study LMS FFR 0.88 – No significant step-up on FFR 0.88 – No significant step-up on

hyperaemic pull-backhyperaemic pull-back

Proceed to PCI of RCA CTO….Proceed to PCI of RCA CTO….

Case 2 - StableCase 2 - Stable

Left main disease in acute Left main disease in acute coronary syndromescoronary syndromes

Case 1 - UnstableCase 1 - Unstable

Case 1 - UnstableCase 1 - Unstable

Case 2 - UnstableCase 2 - Unstable

Case 2 - UnstableCase 2 - Unstable

5.5mm2

Case 2 - UnstableCase 2 - Unstable

Practical TipsPractical Tips

Intravenous, centrally administered Intravenous, centrally administered adenosineadenosine

Guide catheter Guide catheter engagement/dampingengagement/damping

Beware distal diseaseBeware distal disease

Differing FFRs in the LAD and CxDiffering FFRs in the LAD and Cx

Intravenous Infusion of Adenosine 140 µg/kg/minIntravenous Infusion of Adenosine 140 µg/kg/min

Adenosine IV Femoral

Pull-back under maximal Pull-back under maximal hyperaemiahyperaemia

Practical TipsPractical Tips

Intravenous, centrally administered Intravenous, centrally administered adenosineadenosine

Guide catheter Guide catheter engagement/dampingengagement/damping

Beware distal diseaseBeware distal disease

Differing FFRs in the LAD and CxDiffering FFRs in the LAD and Cx

3 mm3 mm

3 mm3 mm

3 mm3 mm 1.8 mm1.8 mm

2.1 mm2.1 mm

2.4 mm2.4 mm64%64%

49 %49 %

36 %36 %

AreaAreaStenosisStenosis

8F8F

7F7F

6F6F

Guiding Catheter in Ostium = StenosisGuiding Catheter in Ostium = Stenosis

Practical TipsPractical Tips

Intravenous, centrally administered Intravenous, centrally administered adenosineadenosine

Guide catheter Guide catheter engagement/dampingengagement/damping

Beware distal diseaseBeware distal disease

Differing FFRs in the LAD and CxDiffering FFRs in the LAD and Cx

PPaa

BB

AA

PPmm

PPdd

FFR(A)FFR(A)predpred = =PPdd - (P - (Pmm/P/Paa) P) Pww

PPaa - P - Pmm + P + Pdd -P -Pww

FFR(B)FFR(B)predpred = = (P(Paa - P - Pww) (P) (Pm m - P- Pdd))

PPaa (P (Pmm - P - Pww))

PPww == Coronary occlusive pressureCoronary occlusive pressure De Bruyne et al, Circulation 2000

Practical TipsPractical Tips

Intravenous, centrally administered Intravenous, centrally administered adenosineadenosine

Guide catheter Guide catheter engagement/dampingengagement/damping

Beware distal diseaseBeware distal disease

Differing FFRs in the LAD and CxDiffering FFRs in the LAD and Cx

FFR = 0.90

FFR = 0.63

ConclusionsConclusions

Pressure wire assessment of the LMS Pressure wire assessment of the LMS is technically easyis technically easy

Medical treatment when the Medical treatment when the FFR>0.75 seems safeFFR>0.75 seems safe

Use central, iv adenosine and Use central, iv adenosine and disengage the guide catheter before disengage the guide catheter before measuringmeasuring

Beware underestimating FFR with Beware underestimating FFR with downstream diseasedownstream disease