Pressure Wire Evaluation of the Left Main Stem Dr Phil MacCarthy Consultant Cardiologist King’s Cardiac Centre Left Main 5+ at AA2007, Jan 24 th, 2007.

No conflicts of interest

Assessment of critical LMS disease is sometimes easy…

A more common clinical scenario

How do you currently establish the haemodynamic importance of a LMS lesion? Surgery!

The stakes are high…

The angiogram is a 2D representation of a complex 3D structure Topol and Nissen, Circulation 1995

Correlation between LMS anatomy and physiology Jasti et al, Circulation 2004

Studies of LMS FFR vs Outcome ReferencenFFR<0.75 FFR>0.75 (Deferred) F/U (months) Mortality in deferred group Bech et al Heart Jimenez- Navarro et al J Inv Cardiol Jasti et al Circulation (all non- cardiac) Suemaru et al Heart Vessels Legutko et al Kardiol Pol Lindstaedt et al Am Heart J

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

Case 1 - Stable

Case 2 - Stable

Pressure-wire study LMS Pressure-wire study LMS FFR 0.88 – No significant step-up on hyperaemic pull-back FFR 0.88 – No significant step-up on hyperaemic pull-back Proceed to PCI of RCA CTO…. Proceed to PCI of RCA CTO….

Case 2 - Stable

Left main disease in acute coronary syndromes

Case 1 - Unstable

Case 2 - Unstable

5.5mm 2

Case 2 - Unstable

Practical Tips Intravenous, centrally administered adenosine Intravenous, centrally administered adenosine Guide catheter engagement/damping Guide catheter engagement/damping Beware distal disease Beware distal disease Differing FFRs in the LAD and Cx Differing FFRs in the LAD and Cx

Intravenous Infusion of Adenosine 140 µg/kg/min Adenosine IV Femoral

Pull-back under maximal hyperaemia

Practical Tips Intravenous, centrally administered adenosine Intravenous, centrally administered adenosine Guide catheter engagement/damping Guide catheter engagement/damping Beware distal disease Beware distal disease Differing FFRs in the LAD and Cx Differing FFRs in the LAD and Cx

3 mm 1.8 mm 2.1 mm 2.4 mm 64% 49 % 36 % AreaStenosis 8F 7F 6F Guiding Catheter in Ostium = Stenosis

Practical Tips Intravenous, centrally administered adenosine Intravenous, centrally administered adenosine Guide catheter engagement/damping Guide catheter engagement/damping Beware distal disease Beware distal disease Differing FFRs in the LAD and Cx Differing FFRs in the LAD and Cx

PaPaPaPa B A PmPmPmPm PdPdPdPd FFR(A) pred = P d - (P m /P a ) P w P a - P m + P d -P w FFR(B) pred = (P a - P w ) (P m - P d ) (P a - P w ) (P m - P d ) P a (P m - P w ) P w = Coronary occlusive pressure De Bruyne et al, Circulation 2000

Practical Tips Intravenous, centrally administered adenosine Intravenous, centrally administered adenosine Guide catheter engagement/damping Guide catheter engagement/damping Beware distal disease Beware distal disease Differing FFRs in the LAD and Cx Differing FFRs in the LAD and Cx

FFR = 0.90 FFR = 0.63

Conclusions Pressure wire assessment of the LMS is technically easy Pressure wire assessment of the LMS is technically easy Medical treatment when the FFR>0.75 seems safe Medical treatment when the FFR>0.75 seems safe Use central, iv adenosine and disengage the guide catheter before measuring Use central, iv adenosine and disengage the guide catheter before measuring Beware underestimating FFR with downstream disease Beware underestimating FFR with downstream disease