| Literature DB >> 33717470 |
Claire E Raphael1, Peter D O'Kane2.
Abstract
Bifurcation lesions are common and associated with higher risks of major cardiac events and restenosis after percutaneous coronary intervention (PCI). Treatment requires understanding of lesion characteristics, stent design and therapeutic options. We review the evidence for provisional vs 2-stent techniques. We conclude that provisional stenting is suitable for most bifurcation lesions. We detail situations where a 2-stent technique should be considered and the steps for performing each of the 2-step techniques. We review the importance of lesion preparation, intracoronary imaging, proximal optimization (POT) and kissing balloon inflation.Entities:
Keywords: Bifurcation; DK crush; PCI; culotte
Year: 2021 PMID: 33717470 PMCID: PMC7917419 DOI: 10.1177/2048004021992190
Source DB: PubMed Journal: JRSM Cardiovasc Dis ISSN: 2048-0040
Figure 1.The Medina classification is based on anatomic lesions, giving each bifurcation a 3 digit binary code. If there is a lesion >50%, it is classified as “1” and if <50% it is a “0”. The first figure represents the proximal main vessel, the second, the distal main vessel and the third the side branch. Each classification is demonstrated in the figure. Reproduced from Ali et al.[2]
Figure 2.The DEFINITION study grouped bifurcation lesions into “complex” and “simple” lesions using criteria that predicted major adverse events post PCI. A complex lesion is defined as meeting the criteria in the first box and with at least two of the characteristics listed in the second box (adapted from Melikian et al.[3]).
Figure 3.Importance of proximal optimization technique (POT). The POT balloon is sized 1:1 to the proximal MV. If the balloon is too proximal, there will be incomplete expansion of stent at the ostial SB and a risk of proximal edge dissection if the proximal balloon is outside of the stent. A too distal POT will deform the stent causing carina shift and reduction in the size of the ostial SB. The distal MV may be traumatized by the oversized balloon. There is also a risk of missing the proximal aspect of the stent which would then be under-expanded and unopposed to the vessel wall. Figure adapted from EBC.[10]
Figure 4.OCT may be used to guide recrossing during bifurcation PCI. Here, a fly through image shows a proximal cell re-cross into the circumflex in a distal left main bifurcation.
Figure 5.Provisional stent approach. A single stent is placed across the bifurcation. The proximal stent is optimised (POT) with a non compliant balloon sized to the proximal main vessel size. Rewiring of the side branch and kissing balloon inflation are commonly performed to optimize the ostium of the side branch but are not mandatory.
Figure 6.The culotte technique. This is most suited to lesions where the SB and the distal MW are of similar caliber. The SB is stented first, followed by a POT and rewiring of the MV, aiming for a proximal cross of the stent struts. The stent struts are opened with a low profile balloon and the MV stented. A further POT is performed before rewiring of the SB to minimize the risk of abluminal wiring. KBI inflation is performed, sized to the distal vessels.
Figure 7.T stent/TAP, treating MV first. The first 4 steps of this procedure are the same as provisional stenting so this can be used as a bailout technique if there is a large dissection in the SB or compromise of SB flow, converting the provisional strategy to a T stent/TAP strategy.
Figure 8.DK crush technique. This is the most complex of the bifurcation techniques. It has the advantage of maintaining wire access in the MV throughout. Two KBI (unlike classic or mini-crush) are performed which increases the success of re-cross after MV stenting.
Key trials in non-LMS bifurcation stenting.
| Trial | n | Comparator arm 1 | Comparator arm 2 | Primary endpoint | Results |
|---|---|---|---|---|---|
| NORDIC Bifurcation Study I 200618 | 413 | PS | 2 stent (classic crush, T-stenting, culotte) | MACE (death, MI, TVR, ST) at 6 months | Similar MACE between groups. Longer procedure time and higher rates of raised biomarkers post procedure in 2-stent group |
| DK crush 1 200815 | 311 | Classic crush | DK crush | MACE (cardiac death, MI, TVR) at 8 months | DK crush associated with lower rates of MACE at 8 months compared to classic crush (11.4% vs 24.4%, p = 0.002). FKBI achieved in 100% of patients treated with DK crush compared to 76% in the classic crush group |
| BBK 1 200819 | 101 | T stent | PS +KBI with bailout T stent if SB compromise | % stenosis of the SB at 9 month angiographic follow up. | No difference in SB stenosis between groups |
| CACTUS 200920 | 350 | PS with bailout T stent | Classic crush | 6 month angiographic restudy | Difference in re-stenosis between the two groups in either the MV or SB. Rates of major adverse events (cardiac death, MI, TLR) at 6 months similar between groups |
| BBC ONE 201021 | 500 | PS with optional FKB | 2-stent (crush, T, culotte) with mandatory FKB | MACE (death, MI, TVF) | Higher rates of MACE in 2-stent compared to PS (8% vs 15%, p = 0.009), largely driven by periprocedural MI. 2-stent procedures had longer duration and fluroscopy time |
| DK crush 2 201122 | 370 | DK crush | PS | MACE (cardiac death, MI, TVR) | No difference in MACE between groups. DK crush associated with a significant reduction of TLR and TVR. |
| Nordic Baltic III 201123 | 477 | PS+FKB | PS without FKB | MACE (death, MI, TVF) | No difference in MACE. Lower rates of SB stenosis in the FKB group (7.9% vs 15.4%, p = 0.039) on 8 month angiographic study |
| BBC 1/Nordic Bifurcation 5 year follow up[ | 890 | PS | 2 stent (classic crush, T-stenting, culotte) | all cause mortality at 5 years | Lower mortality with PS vs 2 stent (3.8% vs 7.0%, p = 0.04) |
| DK crush 6 201524 | 320 | PS approach. Decision to stent SB guided by FFR | PS approach. Decision to stent SB made angiographically | 1 year composite MACE (cardiac death, MI and clinically driven TLR) | No difference in MACE between groups. Numerically lower % of SB stent in FFR group (56% vs 63%, p = 0.07) |
| Nordic II 200925 | 424 | Culotte | Classic Crush | MACE (cardiac death, MI, TVR or ST) at 6 months | No diference in MACE between groups (crush 4.3%, culotte 3.7%, p = 0.87). Similar procedure and fluroscopy times. Trend towards less in segment restenosis and in stent restenosis with culotte compared to crush |
| EBC TWO 201626 | 200 | PS | Culotte | MACE (death, MI, TVR) at 12 months. | No difference in MACE (7.7% in T stent vs 10.3% in culotte, p = 0.53) |
| BBK II 201618 | 300 | Culotte | TAP | Restenosis at 9 month angiographic follow up. | Culotte group had lower % of angiographic restenosis (21 +/-20% vs 27+/-25, p = 0.006). Trend to lower TLR rates (6% vs 12%, p = 0.069), TLF numerically lower (6.7% vs 12.0%, p = 0.11) |
| PERFECT 2015 - first randomization[ | 306 | FKB | no FKB | Angiographic assessment at 8 months. MACE at 12 months )death, MI, TVR) | Angiographic restenosis was higher in the MV in FKB group compared to no FKB (15.1% vs 3.7%, p = 0.004). No difference in the SB (2.8% vs 5.6%, p = 0.5). No difference in MACE (14.0% versus 11.6%, p = 0.57) |
| PERFECT 2015 - second randomization[ | 419 | PS | Mini crush | as above | No difference in angiographic restenosis between groups in the SB or MV. MACE similar between groups at 1 year (17.9 vs 18.5%, p = 0.84) |
| CELTIC (2018)[ | 170 | Culotte with Xience (3 connector design) | Culotte with Synergy stent (2 connector design) | MACE:death, MI, CVA and TVR. | Synergy non-inferior to Xience (9 month MACE 19% for Xience and 16% for Synergy) |
| DEFINITION II (2020)[ | 653 | PS: complex bifurcation lesions (DEFINITIONS criteria) | 2 stent (77% DK crush). Complex bifurcation lesions (DEFINITIONS criteria) | TLF at 1 year (cardiac death, target vessel MI, clinically driven TLR) | Favored 2 stent technique for complex bifurcation lesions; TLF occurred in 37 (11.4%) in the PS and 20 (6.1%) patients in the 2-stent group, respectively, HR 0.52, 95% CI 0.30–0.90; P = 0.019, largely driven by target vessel MI and clinically driven TLR in the PS group |
PS – provisional stent, POT – proximal optimization technique, MI – myocardial infarction, TVR – target vessel revascularization, ST – stent thrombosis, DK – double kiss, MACE – major adverse cardiac events, FKBI – final kissing balloon inflation, SB – side branch, TLR – target lesion revasularisation, MV – main vessel, LMS – left mainstem, FFR – fractional flow reserve, TIMI – thrombolysis in myocardial infarction, TLF – target lesion failure, TAP – T stent and protrude.
Key trials in LMS bifurcation stenting (abbreviations as per Table 1).
| LMS trials | ||||||
|---|---|---|---|---|---|---|
| Trial | n | Patient population | Comparator arm 1 | Comparator arm 2 | Primary endpoint | Results |
| DK crush 3 201313 | 419 | Unprotected distal LM bifurcation lesions (Medina 1,1,1 or 0,1,1) | DK crush | Culotte | MACE (cardiac death, MI and TVR) | Higher rates of MACE following culotte vs DK crush (16.3% vs 6.2%, p < 0.05), mainly driven by increased TVR (11% vs 4.3%, p < 0.05) |
| EXCEL (2016)[ | 1905 | Unprotected LMS disease of low/intermediate complexity (Syntax score 32 or less) | PCI | CABG | composite of death from any cause, stroke, or MI at 3 years | Primary endpoint in 15.4% of PCI group vs 14.7% of CABG group (P = 0.02 for noninferiority, p = 0.98 for superiority). Secondary end-point of death, stroke, MI at 30 days occurred in 4.9% of PCI group vs 7.9% of CABG group (P < 0.001 for noninferiority, P = 0.008 for superiority). |
| NOBLE (2016)[ | 598 | Unprotected LMS disease | PCI | CABG | MACCE at 5 years: composite of all-cause mortality, non-procedural MI, any repeat coronary revascularisation, stroke | MACCE at 5 years: 28% for PCI (121 events) vs 18% for CABG (80 events). HR 1.51 (95% CI 1.1-2.0). CABG was statistically superior to PCI (p = 0.004). |
| DK crush 5 201730 | 482 | Unprotected distal LM bifurcation lesions (Medina 1,1,1 or 0,1,1) | PS | DK crush | Composite of TLF: cardiac death, target vessel MI, or clinically driven TLR at 1 year | Lower rates of TLF with DK crush vs PS (10.7% vs 5.0%, p = 0.02) |
Pros and cons of 2 stent techniques.
| 2 stent technique | Pros | Cons |
|---|---|---|
| PS |
• Most simple technique • Can be converted to T stent/TAP/culotte as bail out • Data supports PS for most bifurcation lesions, except complex and LMS | • Associated with higher rates of MACE in DEFINITIONS II (complex bifurcations) and DK crush V (udLMS) |
| DK crush |
• Data for superiority over PS and culotte in LMS • Maintains wire access in MV |
• Complex with multiple steps • Results may not be replicated in low volume centres/operators • Greater fluroscopy and contrast dye. • Can be difficult to perform through 6 F system (7 F often preferred) |
| T stent/TAP | • Best in bifurcations where SB is at 90⋅ | • May result in geographic miss of ostial SB |
| Culotte | • Best in bifurcation angles < 70∘and where SB is of similar size to distal MV. |
• 2 layers of stent in proximal MB • Multiple steps of re-wiring |