FFR Guided PCI of LAD/Diagonal Bifurcation and OCT Imaging – April 2016
61 year-old male with stable angina and NIDDM presented with CCS Class II angina. A stress MPI revealed moderate inferolateral and mild apical ischemia. A Cardiac Cath on March 14, 2016 revelaed 2V CAD: 80% LAD/Diagonal bifurcation (1,1,1), 80% OM1, total occlusion of LPL1 and normal LV function; SYNTAX Score of 22. Patient underwent successful intervention of LCx-OM1 (Xience Alpine DES 2.75/23mm) and LCx-LPL1 (PTCA and Xience Alpine DES 2.75/18mm). Patient is now planned for FFR guided PCI of LAD/Diagonal bifurcation and OCT imaging for decision making of side branch intervention.
QWhat are practical lessons from your didactics on bifurcation: when you should protect a side branch with a guide wire?
A.Bases on the published literature and personal experience, side branch should be protected by the guide wire once it is >50% stenosed and >2 mm in size.
QWhen would you treat with a balloon or a stent?
A.Diseased side branch (>70% stenosis in a vessel 2-2.75mm size) should be treated by atherotomy cutting balloon or by non-complaint balloon dilatation. If there is a flow limiting dissection, then only bailout stenting should be done pre or post main vessel stenting. Larger side branch (>2.75mm) should be treated by planned 2 stent approach.
QWhen would you use Gp2b/3a? Which agent? Only intra coronary dose?
A.GP 2b/3a inhibitor is used during bifurcation intervention, when only PTCA of the side branch is done and there is a residual dissection or slow flow. We use IV eptifibatide one or 2 boluses 10 minutes apart during these scenerion, without any subsequent continuous infusion.
QWhen will you keep the patient in the hospital for an extra day - elevation of enzymes, 3X normal?
A.We still routinely check TnI 4-6hrs and for inpatient additional 12-18Hrs post PCI. In cases of TnI >2, CKMB is also measured and we keep the pts in-hospital until CKMB start declining. Yes this practice does increase LOS slightly but in my opinion is a good clinical practice for added observation of these pts.
QDoes side branch occlusion cause increased mortality?
A.Yes large side branch occlusion by causing myocardial necrosis will increase subsequent mortality largely by reducing LVEF or subsequent arrhythmia. Usually these pts have CKMB elevation of >8-10x of baseline. CKMB elevation of 3-5X is usually not associated with higher mortality and data are conflicting for CKMB elevation of 5-8x.
QWith newer stents, are you protecting side branches less?
A.That is correct that newer 3rd generation DES causes less side branch occlusion due to their thin struts and a case can be made of protecting the side branch only if side branch stenosis is >70%.
QHow careful should you be in not having overlapping stents across side branches?
A.From optimal technique point of view, we should avoid the stent overlap at the side branch origin because double layer of stents will increase the side branch closure and also re-crossing the jailed ostium may be difficult.
QFor side branches for angulation >90 degrees, which bifurcation technique will you prefer?
A.For side branch angulation >90% 'T' stenting or minicrush will be the best 2 stent technique.
QWhat are you best 3 indications for OCT presently?
A.Top 3 indications for OCT outside the research trials are: thrombus visualization, measuring TCFA and stent expansion, endothelization, or disappearance (BCS).
QDo you expect broadening of OCT guidelines for PCI?
A.I suspect that with the advent of ABSORB BVS, OCT use will increase for proper BVS expansion and apposition. Overall guidelines broadening the OCT indications, will happen only when we will have the studies correlating the OCT use and improved long-term prognosis.