Tips and Pitfalls in Measurement of FFR during Bifurcation Stenting

Nanjing first hospital

Nanjing cardiovascular hospital

Yefei Chenshaoliang Zhangjunjie

Tips of FFR during bifurcation

• Anatomic construction and physiological functional significance of bifurcation correlate with artherosclerosis;

• Changes of fluid hydromechanics located at bifurcation may cause MACE high espically for side branch compared with non-bifurcated lesions;

• Without any standard criteria of FFR at diagnosis of bifurcation lesions now, we still use FFR value of 0.75 or 0.80 for both side branch and main branch according to non-bifurcated lesions.

Limitation of angiography or other imaging for bifurcation lesions

• “Lumenogram” from 2-D view;• Discrepancy between angiography and physiology of

coronary artery tree;• It can not provide any physiological information of

culprit lesion including IVUS and OCT;• Sometimes it is very hard to obtain optimal

angiographc views in order to be able to visualize, describe and classify bifurcation lesions; even moer ignore a very important true bifurcation leison;

• It can not provide any physiological issue after stenting

FFR measurement of bifurcation

• Preparing for FFR measurement of bifurcation lesions is the same as conventional FFR measurement;

• Measuring FFR one by one of both SB and MB;• Measuring start from difficult branch;• Intravenous adenosine is recommended for lasting for

longer time in order to achieve both branch FFR value;

• Normalizing should be achieved before FFR measurement of every branch.

Pitfalls in FFR Measurement of Bifurcation

• Guiding Catheter: avoid deep seating during checking FFR, avoid side hole guiding catheter, avoid 7F or larger guiding catheter

• Wire Issues: avoid pressure line drift, be sure connecting of distal end of the pressure wire and Interface connector, avoid torque the pressure wire more because it is not same as a conventional BMW wire

• Inadequate Hyperemia: intravenous adenosine is recommended which should be administered via central vein or may require higher doses (>140 ug/kg/min) if given peripherally

• Patient Subsets: avoid culprit vessel measurement of AMI or OMI patients, LVH

Pitfalls in FFR Measurement of Bifurcation

If we get a result of FFR <0.75 of both two branches, the CAG result could be found as follow:

Only 3 of them are defined as true bifurcation lesions

Pitfalls in FFR Measurement of Bifurcation

• Diffuse disease or tandem lesions are very often occur at bifurcation, so sometimes it’s difficult to define the accurate FFR value of both branches because there is a severe and diffuse lesion at proximal bifurcation, FFR of SB includes proximal MB and proximal SB, FFR of MB includes proximal MB and distal MB;

• It very hard to decide 1- or 2- stent strategy for bifurcation only according to FFR value, you should combine imaging result with FFR;

FFR or IVUS in diffuse disease or tandem lesions ?

3 mm2 ; FFR = 0.85

5 mm2 ; FFR = 0.60

Pitfalls in FFR Measurement of Bifurcation

中心 Pd′ (SB) Pd(SB)

SB

MB

Pd(MB)

Pd′ (MB)

Pa′

Pa

Proximal MB lesion

Distal MB lesion

Distal SB lesion

FFR MB including distal MB lesion and proximal MB lesion

FFR SB including distal SB lesion and proximal MB lesion

Pitfalls in FFR Measurement of Bifurcation

• Pull back recording technique is very important during the measureing of SB and MB FFR;

hyperemia

Distal SB lesionproximalMB lesion

For treatment of bifurcation lesions

• Debate continuing between 1-stent technique and 2-stent technique for true bifurcation lesions according to imaging result, and no data of functional significance;

• No criteria of FFR value of both side and main branch post PCI using 1- or 2-stent technique;

• During BMS era, FFR >0.90 post POBA and >0.94 post stenting for non-bifurcated lesions are acceptable, but how about DES era?

Application of FFR following 1-stent technique for bifurcation

• Ostial SBs are often nipped post MB stenting, for the reasons of stent struts, shifted plaque and shifted carina, but from imaging result it’s very hard to distinguish one by one. The relationship between nipping ostial SB and FFR is poor, the same as nipping SB and MACE;

• In coronary bifurcation lesions, a strategy of routine kissing balloon dilatation of side branch through the MV stent did not improve the 6-month clinical outcome as compared to a strategy of no kissing balloon dilatation, In the kissing balloon dilatation group, the procedure and fluoroscopy time and the use of contrast were significantly increased------NORDIC III.

A bifurcation of 1-stent technique case report

• MAY, m, 70ys

• Angina pectoris for over 1 mon

• Risk factors: EH, EL, DM

• Echo: EF 54%, LVDd 55mm

CAG result

Classification of the bifurcation

From CAG, classification of LCX-OM is 1,1,0 or 1,1,1

But how about functional result and IVUS result?

FFR of LCX-OM bif

LCX-OM

LCX-PL

Is that true of FFR for both MB and SB?

Strategy for the bifurcation lesion only according to FFR result

1-stent strategy or 2-stent strategy?

But from FFR result, we can not define the classification 1,1,1 or 1,1,0 or 1,0,0.

IVUS of LCX-OM bif

No plaque at ostial LCX-PL,

so classification of the bifurcation lesion is 1,1,0

Strategy for the bifurcation is 1-stent technique

Last result-after stenting

IVUS of last result

Follow-up after 10 month

IVUS result at follow-up

FFR result at follow-up

LCX-OM

LCX-PL

Application of FFR following 2-stent strategy for bifurcation

• Lack of data

• We have designed a randomized trial to compare 1- or 2-stent strategy for true bifurcation leisons using FFR follow-up, it’s still on working……

Early data of our study shows

that……

We still wait for the follow-up result

FFR in bifurcation stenting

• Used up-front to “plan” strategy:

main branch and side branch both ischemic >>> need bifurcational stenting

• Assess outcome of main branch stenting (however, not as good as IVUS or OCT to determine stent apposition, full expansion, etc)

• Assess need for provisional “jailed” sidebranch after main branch treated and outcome of sidebranch therapy (balloon or stent)

Take home messages

• Measurement of FFR during Bifurcation Stenting need more studies;

• FFR guiding strategy for bifurcation lesions should combined with imaging result as IVUS or OCT,et al.

• Advantages of FFR for bifurcation may be on the prognosis of outcome rather than strategy of PCI.

• What is the optimized value of FFR after bifurcation stenting post 1- or 2-stent strategy should be studied more, maybe DK IV trial will give us the answer in the future……

Thanks for your attention