Characteristics of drug-eluting stent platforms potentially influencing bifurcated lesion provisional stenting procedure

Three-Year Outcomes After Bifurcation Stenting With Zotarolimus-Eluting Stents: Final Results From the RESOLUTE ONYX Postapproval Study

Background

Bifurcation represents a challenging lesion subset for percutaneous coronary intervention.

Methods

In this prospective study of the Resolute Onyx zotarolimus-eluting stent (ZES), patients with a single bifurcation target lesion who underwent planned treatment using a provisional stenting technique were enrolled at 25 centers in the United States and Europe. The primary end point was target-vessel failure (TVF) at 1 year, and follow-up was performed through 3 years.

Results

A total of 205 patients were enrolled. Mean age was 66.6 ± 10.7 years, 21.5% of patients were female, and diabetes mellitus was present in 30.2%. A provisional approach with a single stent was performed in 96.6% of patients. The rate of TVF at 1 year was 7.4%, fulfilling the prespecified performance criterion (upper 1-sided 95% CI of 11.1%, compared with the performance goal of 24.5%). At 3-year follow-up, the rate of TVF was 12.1%, the rate of clinically driven target-lesion revascularization was 6.0%, and there were no episodes of stent thrombosis related to the target lesion. Event rates were consistent among the cohort of patients with angiographic core laboratory-confirmed bifurcation lesions.

Conclusions

In this prospective, multicenter study, bifurcation lesion treatment with Resolute Onyx ZES using a planned provisional stent approach was associated with favorable clinical outcomes through 3 years. These results support the longer-term safety and effectiveness of Resolute Onyx ZES to treat bifurcation lesions that are amenable to a planned provisional stenting technique.

Under-deployment of extra-large drug-eluting stent: an adapted provisional technique for selected patients with distal lesions in large left main

BACKGROUND

In provisional technique, main vessel (MV) drug-eluting stent (DES) diameter is usually selected according to distal MV to reduce carina shift. Proximal optimization technique (POT) is used to expand the DES in the proximal MV. Occasionally, the size discrepancy between left main (LM) and left anterior descending artery (LAD) may be huge and this may cause stent malapposition and poor vessel wall coverage in large-sized LM. Recently, some manufactures designed extra-large DES to treat large vessels.

METHODS

We developed an "adapted" provisional strategy based on under-deployment of extra-large DES in case of major size mismatch between LM and proximal LAD. Bench tests were realized in appropriately designed LM bifurcation model using an extra-large DES (Onyx XL, Medtronic, Santa Rosa, CA, USA). This technique was adopted when such "rare" anatomy was found in our clinical practice.

RESULTS

At bench test, Onyx XL 4.5 mm stent reaches 3.8 mm at 5-6 atmospheres, with favorable stent deformation achieved after POT, kissing balloon and re-POT. This technique was performed in 10 patients undergoing unprotected LM stenting with large LM and major mismatch toward LAD. Angiographic success was achieved in all cases and optical coherence tomography assessment was performed in 5 patients revealing optimal stent result. After a follow-up of 557 days (range: 90-1369 days), clinical course was uneventful in all treated patients.

CONCLUSIONS

Under-deployment of extra-large DES is a technical option that can be considered to optimize the provisional stenting technique in selected patients with major diameter mismatch between large-sized LM and LAD.

Clinical outcome after percutaneous coronary intervention with drug-eluting stent in bifurcation and nonbifurcation lesions: a meta-analysis of 23 981 patients

BACKGROUND

PCI in CBL is common and technically demanding. Whether such patients have adverse outcome during the follow-up after successful PCI is unclear. We aim to compare the clinical outcome after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation of coronary bifurcation lesions (CBL) and non-CBL.

METHODS

We performed a systematic literature search to identify studies reporting the clinical outcome of patients undergoing PCI in CBL or not. Patients with left main disease constituted a predefined subgroup. Primary study end-point was major adverse cardiac events (MACE).

RESULTS

Fifteen publications on 23 891 patients with coronary artery disease treated by DES in CBL or not were identified. Median follow-up length was 24 months (range: 12-60). MACE at the longest available follow-up were significantly higher in CBL as compared with non-CBL (19.0 vs. 12.1%, P < 0.001). Similar results were obtained in the subanalysis restricted to second-generation DES studies. The MACE rate was higher early, then decreased during the follow-up being, however, appreciable at all timings up to 36 months. In the left main (LM) subanalysis (four studies, 3210 patients), patients underwent DES implantation in distal LM, as compared with nondistal LM, had increased the MACE rate during the follow-up (27.4 vs. 17.4%, P < 0.001), which was driven by higher target vessel revascularization.

CONCLUSIONS

In the contemporary DES era, CBL represent a subset of lesions associated with increased rate of MACE after PCI. This data prompt for studies aimed at improving the clinical outcomes of patients with CAD.

Coronary bifurcations treated with thin-strut drug-eluting stents: a prespecified analysis of the randomized BIO-RESORT trial

BACKGROUND

Treatment of a coronary bifurcation lesion is often required in routine clinical practice, but data on the performance of very thin-strut biodegradable polymer drug-eluting stents are scarce.

METHODS

Comparison of biodegradable polymer and durable polymer drug-eluting stents in an all comers population (BIO-RESORT) is a prospective, multicenter randomized clinical trial that included 3514 all-comer patients, who were randomized to very thin-strut biodegradable polymer-coated sirolimus- or everolimus-eluting stents, versus thin-strut durable polymer-coated zotarolimus-eluting stents. The approach of bifurcation stenting was left at the operator's discretion, and provisional stenting was generally preferred. This prespecified analysis assessed 3-year clinical outcome of all patients in whom treatment involved at least one bifurcation with a side-branch diameter ≥1.5 mm.

RESULTS

Of all BIO-RESORT trial participants, 1236 patients were treated in bifurcation lesions and analyzed. Single- and two-stent techniques were used in 85.8% and 14.2%, respectively. 'True' bifurcation lesions (main vessel and side-branch obstructed) were treated in 31.1%. Three-year follow-up was available in 1200/1236 (97.1%) patients. The main endpoint target vessel failure (composite of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization) occurred in sirolimus-eluting stents in 42/412 (10.3%) and in zotarolimus-eluting stents in 49/409 (12.1%) patients (P-logrank = 0.40). In everolimus-eluting stents, target vessel failure occurred in 40/415 (9.8%) patients (vs. zotarolimus-eluting stents: P-logrank = 0.26). There was no between-stent difference in individual components of target vessel failure. Findings were consistent in patients with single-vessel treatment and patients treated with a single-stent technique.

CONCLUSIONS

Three years after stenting all-comers with bifurcation lesions, clinical outcome was similar with the sirolimus-eluting and everolimus-eluting stents versus the zotarolimus-eluting stent.

European Bifurcation Club white paper on stenting techniques for patients with bifurcated coronary artery lesions

BACKGROUND

Defining the optimal conduction of percutaneous-coronary-intervention (PCI) to treat bifurcation lesions has been the subject of many clinical studies showing that the applied stenting technique may influence clinical outcome. Accordingly, bifurcation stenting classifications and technical sequences should be standardized to allow proper reporting and comparison.

METHODS

The European Bifurcation Club (EBC) is a multidisciplinary group dedicated to optimize the treatment of bifurcations and previously created a classification of bifurcation stenting techniques that is based on the first stent implantation site. Since some techniques have been abandoned, others have been refined and dedicated devices became available, EBC promoted an international task force aimed at updating the classification of bifurcation stenting techniques as well as at highlighting the best practices for most popular techniques. Original descriptive images obtained by drawings, bench tests and micro-computed-tomographic reconstructions have been created in order to serve as tutorials in both procedure reporting and clinical practice.

RESULTS

An updated Main-Across-Distal-Side (MADS)-2, classification of bifurcation stenting techniques has been realized and is reported in the present article allowing standardized procedure reporting in both clinical practice and scientific studies. The EBC-promoted task force deeply discussed, agreed on and described (using original drawings and bench tests) the optimal steps for the following major bifurcation stenting techniques: (a) 1-stent techniques ("provisional" and "inverted provisional") and (b) 2-stent techniques ("T/TAP," "culotte," and "DK-crush").

CONCLUSIONS

The present EBC-promoted paper is intended to facilitate technique selection, reporting and performance for PCI on bifurcated lesions during daily clinical practice.

Structural and Hemodynamic Analyses of Different Stent Structures in Curved and Stenotic Coronary Artery

Coronary artery stenting is commonly used for the treatment of coronary stenosis, and different stent structures indeed have various impacts on the stress distribution within the plaque and artery as well as the local hemodynamic environment. This study aims to evaluate the performance of different stent structures by characterizing the mechanical parameters after coronary stenting. Six stent structures including three commercially-shaped stents (Palmaz-Schatz-shaped, Xience Prime-shaped, and Cypher-shaped) and three author-developed stents (C-Rlink, C-Rcrown, and C-Astrut) implanted into a curved stenotic coronary artery were investigated. Structural analyses of the balloon-stent-plaque-artery system were first performed, and then followed by hemodynamic analyses. The results showed that among the three commercially-shaped stents, the Palmaz-Schatz-shaped had the least stent dogboning and recoiling, corresponding to the greatest maximum plastic strain and the largest diameter change, nevertheless, it induced the highest maximum von Mises stress on plaque, arterial intima and media. From the viewpoint of hemodynamics, the Palmaz-Schatz-shaped displayed smaller areas of adverse low wall shear stress (<0.5 Pa), low time-averaged wall shear stress (<0.5 Pa), and high oscillating shear index (>0.1). Compared to the Cypher-shaped, the C-Rcrown and C-Astrut had smaller recoiling, greater maximum plastic stain and larger diameter change, which indicated the improved mechanical performance of the Cypher-shaped stent. Moreover, both C-Rcrown and C-Astrut exhibited smaller areas of adverse low wall shear stress, and low time-averaged wall shear stress, but only the C-Rcrown displayed a smaller area of adverse high oscillating shear index. The present study evaluated and compared the performance of six different stents deployed inside a curved artery, and could be potentially utilized as a guide for the selection of suitable commercially-shaped stent for clinical application, and to provide an approach to improve the performance of the commercial stents.

Treatment strategies for coronary bifurcation lesions made easy in the current era by introduction of the BIFURCAID app

Coronary bifurcation lesions account for 15-20% of all percutaneous coronary interventions. Percutaneous revascularization of these lesions is technically challenging and results in lower success rates than nonbifurcation lesions. There are unique procedural considerations and techniques that are employed in the percutaneous revascularization of these lesions. Our objective is to define the procedural complexities of treating coronary bifurcation lesions and describe the leading provisional and dedicated two stent techniques used to optimize procedural and clinical results, as described in the BIFURCAID app.

Long-term outcome and chest pain in patients with true versus non-true bifurcation lesions treated with second-generation drug-eluting stents in the TWENTE trial

The objective of this study is to assess 3-year clinical outcome of patients with true bifurcation lesions (TBLs) versus non-true bifurcation lesions (non-TBLs) following treatment with second-generation drug-eluting stents (DES). TBLs are characterized by the obstruction of both main vessel and side-branch. Limited data are available on long-term clinical outcome following TBL treatment with newer-generation DES. We performed an explorative sub-study of the randomized TWENTE trial among 287 patients who had bifurcated target lesions with side-branches ≥2.0 mm. Patients were categorized into TBL (Medina classes: 1.1.1; 1.0.1; 0.1.1) versus non-TBL to compare long-term clinical outcome. A total of 116 (40.4 %) patients had TBL, while 171 (59.6 %) had non-TBL only. Target-lesion revascularization rates were similar (3.5 vs. 3.5 %; p = 1.0), and definite-or-probable stent thrombosis rates were low (both <1.0 %). The target-vessel myocardial infarction (MI) rate was 11.3 versus 5.3 % (p = 0.06), mostly driven by (periprocedural) MI ≤48 h from PCI. All-cause mortality and cardiac death rates were 8.7 versus 3.5 % (p = 0.06) and 3.5 versus 1.2 % (p = 0.22), respectively. The 3-year major adverse cardiac event rate for patients with TBL versus non-TBL was 20.0 versus 11.7 % (p = 0.05). At 1-, 2-, and 3-year follow-up, 6.5, 13.0, and 11.0 % of patients reported chest pain at less than or equal moderate physical effort, respectively, without any between-group difference. Patients treated with second-generation DES for TBL had somewhat higher adverse event rates than patients with non-TBL, but dissimilarities did not reach statistical significance. Up to 3-year follow-up, the vast majority of patients of both groups remained free from chest pain.

Stenting of coronary bifurcation lesions: a literature and technical review

Newer generation drug-eluting stents have improved outcomes in various subsets of coronary lesions including bifurcation lesions. This article reviews the current literature on various issues in bifurcation percutaneous coronary intervention (PCI). Generally, the provisional approach of placing one stent in the main vessel is the preferred first-line treatment for most bifurcation lesions. However, some lesions require 2-stenting. It is unknown whether 2nd-generation DES have improved outcomes with 2-stenting. The use of fractional flow reserve (FFR) for the assessment of functional significance of the jailed side branch can help avoid unnecessary stenting in complex lesions. Skilled techniques in every step of the 2-stenting process and meticulous use of imaging techniques including IVUS or OCT are warranted to obtain optimal angiographic and clinical results. Dedicated bifurcation stents are feasible treatment options and may change future concepts in bifurcation PCI, although larger trials with control groups are required in order to widely apply these techniques into daily routine practice.

Quantitative analysis of the side-branch orifice after bifurcation stenting using en-face processing of OCT images: a comparison between Xience V and Resolute Integrity stents

OBJECTIVE

Methods for intravascular assessment of the side-branch (SB) orifice after stenting are not readily available. The aim of this study was to assess the utility of an en-face projection processing for optical coherence tomography (OCT) images for SB evaluation.

METHODS

Measurements of the SB orifice obtained using en-face OCT images were validated using a phantom model. Linear regression modeling was applied to estimated area measurements made on the en-face images. The SB orifice was then analyzed in 88 patients with bifurcation lesions treated with either Xience V (everolimus-eluting stent) or Resolute Integrity [zotarolimus-eluting stent (ZES)]. The SB orifice area (A) and the area obstructed by struts (B) were calculated, and the %open area was evaluated as (A-B)/A*100.

RESULTS

Linear regression modeling demonstrated that the observed departures of the intercept and slope were not significantly different from 0 (-0.12 ± 0.22, P=0.59) and 1 (1.01 ± 0.06, R(2)=0.88, P=0.87), respectively. In cases without SB dilatation, the %open area was significantly larger in the everolimus-eluting stent group (n=25) than in the ZES group [n=32; 89.2% (83.7-91.3) vs. 84.3% (78.9-87.8), P=0.04]. A significant difference in %open area between cases with and those without SB dilatation was demonstrated in the ZES group [91.4% (86.1-94.0) vs. 84.3% (78.9-87.8), P=0.04].

CONCLUSION

The accuracy of SB orifice measurement on an en-face OCT image was validated using a phantom model. This novel approach enables quantitative evaluation of the differences in SB orifice area free from struts among different stent types and different treatment strategies in vivo.

Bifurcation treatment with novel, highly flexible drug-eluting coronary stents in all-comers: 2-year outcome in patients of the DUTCH PEERS trial

Background

Percutaneous coronary intervention (PCI) in bifurcated lesions with second-generation drug-eluting stents (DES) was associated with increased myocardial infarction (MI) rates. Flexible stent designs that accommodate well to vessel tapering may be of benefit in challenging anatomies such as bifurcated target lesions, but so far data are scarce.

Methods

We analyzed the 2-year follow-up data of the DUTCH PEERS (TWENTE II) trial, which randomized 1811 all-comer patients to PCI with newer generation resolute integrity zotarolimus-eluting (Medtronic) or promus element everolimus-eluting stents (Boston Scientific). In bifurcated lesions, provisional stenting was generally performed. Target vessel failure is a composite endpoint, consisting of cardiac death, target vessel MI, or target vessel revascularization.

Results

Patients with at least one bifurcated lesion (n = 465, 25.7 %) versus patients with non-bifurcated target lesions only (n = 1346, 74.3 %) showed similar rates of clinical endpoints including target vessel failure (9.2 versus 7.9 %, p = 0.36) and definite stent thrombosis (0.4 versus 1.0 %, p = 0.38). Target vessel MI was more common in patients with bifurcated lesions (3.4 versus 1.6 %, p = 0.02); but after multivariate analysis with propensity score adjustment, bifurcation treatment was found not to be an independent predictor of target vessel MI (HR 1.40, 95 % CI 0.71–2.76; p = 0.34). Among patients with bifurcated lesions, DES type and side-branch size did not affect outcome, but periprocedural MI occurred more often after two-stent approaches (9.0 versus 2.1 %; p = 0.002).

Conclusion

All-comer patients treated for bifurcated and non-bifurcated target lesions showed similar and low rates of clinical endpoints, suggesting that the DES used are efficacious and safe for treating bifurcated target lesions.

Three-year clinical outcome of patients with bifurcation treatment with second-generation Resolute and Xience V stents in the randomized TWENTE trial

BACKGROUND

Only limited data from large randomized clinical trials have been published on the long-term performance of second-generation drug-eluting stents in bifurcation lesions.

METHODS

We investigated in patients in the randomized TWENTE trial the long-term safety and efficacy of treating bifurcation lesions with 2 widely applied second-generation drug-eluting stents, the zotarolimus-eluting Resolute stent (Medtronic Inc, Santa Rosa, CA) and the everolimus-eluting Xience V stent (Abbott Vascular, Santa Clara, CA). Three-year follow-up was available in 99.3%. Patients were categorized into treatment for ≥1 bifurcation lesion versus treatment for nonbifurcation lesions only.

RESULTS

Among the 1,391 patients of the TWENTE trial, 362 (26%) were treated for bifurcation lesions. At 3-year follow-up, target-vessel failure did not differ between patients treated for bifurcation versus nonbifurcation lesions (13.1% vs 12.6%; P = .84), whereas the periprocedural myocardial infarction rate was higher in patients with bifurcation lesions (6.9% vs 3.1%; P < .01). Of the 362 patients with bifurcation lesion treatment, 179 (49.4%) were treated with Resolute and 183 (50.6%) with Xience V. There was no significant difference in target-vessel failure between the Resolute and Xience V groups with bifurcation treatment (13.6% vs 12.6%; P = .78), and their incidence of definite-or-probable stent thrombosis was low and similar (1.1% vs 0.5%, respectively; P = .62).

CONCLUSION

Despite a significant difference in periprocedural myocardial infarction, 3-year clinical outcome after implantation of second-generation stents was favorable and similar for patients with and without bifurcation lesions. In addition, we observed no difference in long-term clinical outcome after bifurcation lesion treatment with Resolute and Xience V stents.