First- versus second-generation drug-eluting stents for the treatment of coronary bifurcations

Development of Innovative Biomaterials and Devices for the Treatment of Cardiovascular Diseases

Cardiovascular diseases have become the leading cause of death worldwide. The increasing burden of cardiovascular diseases has become a major public health problem and how to carry out efficient and reliable treatment of cardiovascular diseases has become an urgent global problem to be solved. Recently, implantable biomaterials and devices, especially minimally invasive interventional ones, such as vascular stents, artificial heart valves, bioprosthetic cardiac occluders, artificial graft cardiac patches, atrial shunts, and injectable hydrogels against heart failure, have become the most effective means in the treatment of cardiovascular diseases. Herein, an overview of the challenges and research frontier of innovative biomaterials and devices for the treatment of cardiovascular diseases is provided, and their future development directions are discussed.

Impact of directional coronary atherectomy followed by drug-coated balloon strategy to avoid the complex stenting for bifurcation lesions

Although the simple single stenting rather than complex double stenting is recommended on percutaneous coronary intervention (PCI) for bifurcation lesions, double stenting cannot always be avoided. We investigated the impact of directional coronary atherectomy (DCA), followed by drug-coated balloon (DCB) treatment to reduce the number of stents and avoid complex stenting in PCI for bifurcation lesions and short-term patency. DCA treatment without stents was attempted for 27 bifurcation lesions in 25 patients, of those, 26 bifurcation lesions in 24 patients were successfully treated and 3-month follow-up angiography and optical coherence tomography (OCT) were performed. Sixteen lesions (59.3%) were related to left main trunk distal bifurcations, and 7 (25.9%) were true bifurcation lesions. Among the true bifurcation lesions, 4 lesions (57.1%) needed 1 stent, and the other 3 lesions (42.9%) needed no stents. Among the non-true bifurcation lesions, 1 lesion (5.0%) needed bailout stent and other lesions (95.0%) needed no stents. According to DCA followed by DCB treatment, the angiographic mean diameter stenosis improved from 65.5 ± 15.0% to 7.8 ± 9.8%, and the mean plaque area in intravascular ultrasound improved from 80.4 ± 10.5% to 39.0 ± 11.5%, respectively. Angiographic and OCT late lumen loss values were 0.2 ± 0.6 mm and 1.4 ± 1.9 mm, respectively. No patient had in-hospital major adverse cardiac events (MACE) and 3-month MACE. In conclusion, compared with standard provisional side branch stenting strategy, DCA followed by DCB treatment might reduce the number of stents, avoid complex stenting for major bifurcation lesions and provide good short-term outcomes.

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.

Efficacy of drug-coated balloon angioplasty after directional coronary atherectomy for coronary bifurcation lesions (DCA/DCB registry)

OBJECTIVES

To evaluate the efficacy and safety of additional drug-coated balloon (DCB) angioplasty after directional coronary atherectomy (DCA) for coronary bifurcation lesions.

BACKGROUND

The optimal therapy for bifurcation lesions has not been established, even in the drug-eluting stent era. DCA possibly prevents plaque and carina shift in bifurcation lesions by plaque debulking; however, the efficacy of combined DCA and DCB (DCA/DCB) for bifurcation lesions remains unclear.

METHODS

This multicenter registry retrospectively recruited patients with bifurcation lesions who underwent DCA/DCB and follow-up angiogram at 6-15 months. The primary endpoint was the 12-month target vessel failure (TVF) rate. The secondary endpoints were procedure-related major complications, major cardiovascular events at 12 months, restenosis at 12 months, target lesion revascularization (TLR) at 12 months, and target vessel revascularization (TVR) at 12 months.

RESULTS

We enrolled 129 patients from 16 Japanese centers. One hundred and four lesions (80.6%) were located around the left main trunk bifurcations. No side branch compromise was found intraoperatively. Restenosis was observed in three patients (2.3%) at 12 months. TLR occurred in four patients (3.1%): 3 (2.3%) in the main vessel and 1 (0.8%) in the ostium of the side branch at 12 months. TVF incidence at 12 months was slightly higher in 14 patients (10.9%), and only two patients (1.6%) had symptomatic TVR. One patient (0.8%) had non-target vessel-related myocardial infarction.

CONCLUSIONS

Our data suggested that DCA/DCB provided good clinical outcomes and minimal side branch damage and could be an optimal non-stent percutaneous coronary intervention strategy for bifurcation lesions.

Prognostic significance of the Medina classification in bifurcation lesion percutaneous coronary intervention with second-generation drug-eluting stents

The Medina classification is the most widespread method to describe bifurcation lesions. However, little is known regarding its prognostic impact. Therefore, the aim of this study is to assess the prognostic significance of the Medina classification following percutaneous coronary intervention (PCI). From a prospective registry of 738 consecutive patients undergoing PCI for bifurcation lesions, 505 were treated with second-generation drug-eluting stents (DES). Of these, 407 (80.6%) presented with "true bifurcation" (TB) lesions (Medina class 1.0.1, 1.1.1, 0.1.1) and 98 (19.4%) in all other categories ("non-true bifurcation" = NTB). We compared rates of death and major adverse cardiac events (MACE: cardiac death, myocardial infarction, or target vessel revascularization) at 12 months and 3 years. Patients with TB had lower rates of previous bypass surgery (7.4% vs. 11.2%, p = 0.043). TB lesions were more likely to be calcified (33.9% vs. 28.6%, p = 0.003) and ulcerated (8.8% vs. 4.1%, p < 0.01). At 12 months, mortality was numerically higher for TB PCI (4.1% vs. 2.1%, p = 0.052) and MACE rates were higher (19.2% vs. 10.2%, p < 0.001). At 3 years, both all-cause death (10.1% vs. 5.1%, p = 0.002) and rates of MACE (37.2% vs. 17.6%, p < 0.001) were higher for TB PCI. After performing regression analysis, TB remained an independent predictor for poor outcomes (OR-2.28 at 12 months, CI 1.45-9.50, p = 0.007, OR-3.75 at 3 years, CI 1.52-6.77, p = 0.001 for MACE). In conclusion, TB lesions, according to the Medina classification, portend worse prognosis for patients undergoing bifurcation PCI. This may guide prognostication and decision-making in treatment.

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.

The Need For Dedicated Bifurcation Stents: A Critical Analysis

There is growing evidence that optimally performed two-stent techniques may provide similar or better results compared with the simple techniques for bifurcation lesions, with an observed trend towards improvements in clinical and/or angiographic outcomes with a two-stent strategy. Yet, provisional stenting remains the treatment of choice. Here, the author discusses the evidence - and controversies - concerning when and how to use complex techniques.

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.