Very thin strut biodegradable polymer everolimus-eluting and sirolimus-eluting stents versus durable polymer zotarolimus-eluting stents in allcomers with coronary artery disease (BIO-RESORT): a three-arm, randomised, non-inferiority trial

Ethnic minorities treated with new-generation drug-eluting coronary stents in two European randomised clinical trials

BACKGROUND

Several ethnic minorities have an increased risk of cardiovascular events, but previous European trials that investigated clinical outcome after coronary stenting did not assess the patients' ethnic background.

AIMS

To compare ethnic minority and Western European trial participants in terms of both cardiovascular risk profile and 1‑year clinical outcome after percutaneous coronary intervention.

METHODS

In the BIO-RESORT and BIONYX randomised trials, which assessed new-generation drug-eluting stents, information on patients' self-reported ethnic background was prospectively collected. Pooled patient-level data of 5803 patients, enrolled in the Netherlands and Belgium, were analysed in this prespecified analysis. The main endpoint was target vessel failure after 1 year.

RESULTS

Patients were classified as belonging to an ethnic minority (n = 293, 5%) or of Western European origin (n = 5510, 95%). Follow-up data were available in 5772 of 5803 (99.5%) patients. Ethnic minority patients were younger, less often female, more often current smokers, more often medically treated for diabetes, and more often had a positive family history of coronary artery disease. The main endpoint target vessel failure did not differ between ethnic minority and Western European patients (3.5% vs 4.9%, hazard ratio 0.71, 95% confidence interval 0.38-1.33; p = 0.28). There was also no difference in mortality, myocardial infarction, and repeat revascularisation rates.

CONCLUSIONS

Despite the unfavourable cardiovascular risk profile of ethnic minority patients, short-term clinical outcome after treatment with contemporary drug-eluting stents was highly similar to that in Western European patients. Further efforts should be made to ensure the enrolment of more ethnic minority patients in future coronary stent trials.

Long-Term Percutaneous Coronary Intervention Outcomes in Chronic Versus Acute Coronary Syndromes (TARGET All Comers Trial)

In the Targeted therapy with a localised abluminal coated, low-dose sirolimus-eluting, biodegreadable polymer coronary stent (TARGET; NCT02520180) All Comers trial the biodegradable polymer (BP) sirolimus-eluting FIREHAWK stent was noninferior to the durable polymer (DP) everolimus-eluting XIENCE stent with respect to target lesion failure (TLF) at 1 and 5 years; however, the long-term safety and efficacy in the setting of acute coronary syndromes (ACS) are not known. We sought to assess the long-term outcomes in ACS versus chronic coronary syndromes (CCS) with BP sirolimus-eluting stent (SES) versus DP everolimus-eluting stent (EES). The TARGET AC study was a multicenter, open-label, noninferiority trial of all comer patients randomly allocated 1:1 to BP SES or DP EES (stratified by ST-elevation myocardial infarction and study site). In this predefined substudy, the outcomes were compared based on clinical presentation (ACS vs CCS) and treatment allocation. A total of 1,653 patients were enrolled (728 with ACS and 922 with CCS), with 94% completing the 5-year follow-up. The baseline characteristics were well-matched between the 2 stent types; however, co-morbidities were more prevalent in the CCS than in the ACS population. TLF (15.5% vs 17.7%, p = 0.24), patient-oriented outcomes (32.0% vs 34.4%, p = 0.31), and stent thrombosis (4.1% vs 3.3%, p = 0.40) were similar between patients with ACS and patients with CCS. In the ACS cohort, the outcomes at 5 years for BP SES versus DP EES were similar for TLF (16.0% vs 14.9%, p = 0.70), ischemia-driven target lesion revascularization (5.6% vs 8.3%, p = 0.17), and definite/probable stent thrombosis (2.7% vs 4.6%, p = 0.18). The same was true for the CCS cohort, with 5-year outcomes for BP SES versus DP EES for TLF (18.0% vs 17.4%, p = 0.82), ischemia-driven target lesion revascularization (6.4% vs 5.0%, p = 0.37), and definite/probable stent thrombosis (3.0% vs 1.8%, p = 0.26). In conclusion, in the TARGET AC trial, 1 in 3 patients had a major adverse event at 5 years, irrespective of CCS or ACS presentation. Long-term, the BP sirolimus-eluting FIREHAWK stent was as safe and effective as the DP everolimus-eluting XIENCE stent across the spectrum of clinical presentations.

Invasiveness of previous treatment for peripheral arterial disease and risk of adverse cardiac events after coronary stenting

Patients with peripheral arterial disease (PADs), undergoing percutaneous coronary intervention (PCI), have higher adverse event risks. The effect of invasiveness of PADs treatment on PCI outcome is unknown. This study assessed the impact of the invasiveness of previous PADs treatment (invasive or non-invasive) on event risks after PCI with contemporary drug-eluting stents. This post-hoc analysis pooled 3-year patient-level data of PCI all-comer patients living in the eastern Netherlands, previously treated for PADs. PADs included symptomatic atherosclerotic lesion in the lower or upper extremities; carotid or vertebral arteries; mesenteric arteries or aorta. Invasive PADs treatment comprised endarterectomy, bypass surgery, percutaneous transluminal angioplasty, stenting or amputation; non-invasive treatment consisted of medication and participation in exercise programs. Primary endpoint was (coronary) target vessel failure: composite of cardiac mortality, target vessel-related myocardial infarction, or clinically indicated target vessel revascularization. Of 461 PCI patients with PADs, information on PADs treatment was available in 357 (77.4%) patients; 249 (69.7%) were treated invasively and 108 (30.3%) non-invasively. Baseline and PCI procedural characteristics showed no between-group difference. Invasiveness of PADs treatment was not associated with adverse event risks, including target vessel failure (20.5% vs. 16.0%; HR: 1.30, 95%-CI 0.75-2.26, p = 0.35), major adverse cardiac events (23.3% vs. 20.4%; HR: 1.16, 95%-CI 0.71-1.90, p = 0.55), and all-cause mortality (12.1% vs. 8.3%; HR: 1.48, 95%-CI 0.70-3.13, p = 0.30). In PADs patients participating in PCI trials, we found no significant relation between the invasiveness of previous PADs treatment and 3-year outcome after PCI. Consequently, high-risk PCI patients can be identified by consulting medical records, searching for PADs, irrespective of the invasiveness of PADs treatment.

Value of stent boost imaging in decision making after coronary stenting

BACKGROUND

Several studies reported the comparability of digital stent enhancement techniques (including stent boost imaging) in detecting suboptimal results of coronary stenting with Intra Vascular Ultrasound and optical coherence tomography.

AIMS

to assess results of stent deployment and determine the incidence of suboptimal results requiring changing final decision using stent boost imaging.

METHODS

This cross-sectional study included 120 patients eligible for PCI were recruited during a period of one year (January 2021 to 2022) using DES.

RESULTS

Suboptimal results were found in 38% of the PCI cases with stents (angiography guided). Importantly it was found that improper lesion preparation in our practice could not help improving stent optimization. Also, angiography guided PCI has significant incidence of suboptimal results. Digital stent enhancement techniques like stent boost have significant and important value in better decision making. After adjusting for age and sex, six factors were identified as independent predictors for final decision change (stent length, LAD/RCA affection, proximal segment affection, calcification, and optical coherence tomography.

CONCLUSION

This study has confirmed the utility of stent boost for the optimization of PCI in daily practice. Stent Boost is a simple and costless technique that provides an accurate assessment of a deployed stent without extending the procedure time and without more risk. It appears to be useful for the immediate evaluation of stent expansion and optimization of PCI by additional post-dilatation, when appropriate. Future studies are needed to determine whether Stent Boost data will correlate with adverse long-term clinical outcomes in patients undergoing PCI.

The relation of polymer structure of stent used in patients with acute coronary syndrome revascularized by stent implantation with long-term cardiovascular events

INTRODUCTION

Drug-eluting stents (DES) have revolutionized percutaneous coronary intervention (PCI) by improving event-free survival compared to older stent designs. However, early-generation DES with polymer matrixes have raised concerns regarding late stent thrombosis due to delayed vascular healing. To address these issues, biologically bioabsorbable polymer drug-eluting stents (BP-DES) and polymer-free drug-eluting stents (PF-DES) have been developed.

AIM

The aim of the present study is to evaluate and compare the long-term effects of different stent platforms in patients with acute coronary syndrome (ACS) undergoing PCI.

MATERIAL AND METHODS

We conducted a retrospective, observational study involving 1192 ACS patients who underwent urgent PCI. Patients were treated with thin- strut DP-DES, ultra-thin strut BP-DES, or thin-strut PF-DES. The primary endpoint was a composite of cardiac death, target vessel myocardial infarction (TVMI), and clinically driven target lesion revascularization (CITLR) at 12 months and 4 years.

RESULTS

The baseline demographics and clinical characteristics of patients in the three stent subgroups were similar. No significant differences were observed in target lesion failure (TLF), cardiac mortality, TVMI, and stent thrombosis (ST) rates among the three subgroups at both 12 months and 4 years. However, beyond the first year, the rate of CITLR was significantly lower in the ultra-thin strut BP-DES subgroup compared to thin-strut DP-DES, suggesting potential long-term advantages of ultra-thin strut BP-DES. Additionally, both ultra-thin strut BP-DES and thin-strut PF-DES demonstrated lower ST rates after the first year compared to thin-strut DP-DES.

CONCLUSION

Our study highlights the potential advantages of ultra-thin strut BP-DES in reducing CITLR rates in the long term, and both ultra-thin strut BP-DES and thin-strut PF-DES demonstrate lower rates of ST beyond the first year compared to thin-strut DP-DES. However, no significant differences were observed in overall TLF, cardiac mortality and TVMI rates among the three stent subgroups at both 12 months and 4 years.

First myocardial infarction in patients with premature coronary artery disease: insights into patient characteristics and outcome after treatment with contemporary stents

AIMS

Patients with premature coronary artery disease (CAD) have a higher incidence of myocardial infarction (MI) than patients with non-premature CAD. The aim of the present study is to asess differences in clinical outcome after a first acute MI, percutaneously treated with new-generation drug-eluting stents between patients with premature and non-premature CAD.

METHODS AND RESULTS

We pooled and analysed the characteristics and clinical outcome of all patients with a first MI (and no previous coronary revascularization) at time of enrolment, in four large-scale drug-eluting stent trials. Coronary artery disease was classified premature in men aged <50 and women <55 years. Myocardial infarction patients with premature and non-premature CAD were compared. The main endpoint was major adverse cardiac events (MACE): all-cause mortality, any MI, emergent coronary artery bypass surgery, or clinically indicated target lesion revascularization. Of 3323 patients with a first MI, 582 (17.5%) had premature CAD. These patients had lower risk profiles and underwent less complex interventional procedures than patients with non-premature CAD. At 30-day follow-up, the rates of MACE [hazard ratio (HR): 0.22, 95% confidence interval (CI): 0.07-0.71; P = 0.005), MI (HR: 0.22, 95% CI: 0.05-0.89; P = 0.020), and target vessel failure (HR: 0.30, 95% CI: 0.11-0.82; P = 0.012) were lower in patients with premature CAD. At 1 year, premature CAD was independently associated with lower rates of MACE (adjusted HR: 0.50, 95% CI: 0.26-0.96; P = 0.037) and all-cause mortality (adjusted HR: 0.24, 95% CI: 0.06-0.98; P = 0.046). At 2 years, premature CAD was independently associated with lower mortality (adjusted HR: 0.16, 95% CI: 0.05-0.50; P = 0.002).

CONCLUSIONS

First MI patients with premature CAD, treated with contemporary stents, showed lower rates of MACE and all-cause mortality than patients with non-premature CAD, which is most likely related to differences in cardiovascular risk profile. TWENTE trials: TWENTE I, clinicaltrials.gov: NCT01066650), DUTCH PEERS (TWENTE II, NCT01331707), BIO-RESORT (TWENTE III, NCT01674803), and BIONYX (TWENTE IV, NCT02508714).

Rationale and design of the PARTHENOPE trial: A two-by-two factorial comparison of polymer-free vs biodegradable-polymer drug-eluting stents and personalized vs standard duration of dual antiplatelet therapy in all-comers undergoing PCI

BACKGROUND

Over the past few decades, percutaneous coronary intervention (PCI) has undergone significant advancements as a result of the combination of device-based and drug-based therapies. These iterations have led to the development of polymer-free drug-eluting stents. However, there is a scarcity of data regarding their clinical performance. Furthermore, while various risk scores have been proposed to determine the optimal duration of dual antiplatelet therapy (DAPT), none of them have undergone prospective validation within the context of randomized trials.

DESIGN

The PARTHENOPE trial is a phase IV, prospective, randomized, multicenter, investigator-initiated, assessor-blind study being conducted at 14 centers in Italy (NCT04135989). It includes 2,107 all-comers patients with minimal exclusion criteria, randomly assigned in a 2-by-2 design to receive either the Cre8 amphilimus-eluting stent or the SYNERGY everolimus-eluting stent, along with either a personalized or standard duration of DAPT. Personalized DAPT duration is determined by the DAPT score, which accounts for both bleeding and ischemic risks. Patients with a DAPT score <2 (indicating higher bleeding than ischemic risk) receive DAPT for 3 or 6 months for chronic or acute coronary syndrome, respectively, while patients with a DAPT score ≥2 (indicating higher ischemic than bleeding risk) receive DAPT for 24 months. Patients in the standard DAPT group receive DAPT for 12 months. The trial aims to establish the noninferiority between stents with respect to a device-oriented composite end point of cardiovascular death, target-vessel myocardial infarction, or clinically-driven target-lesion revascularization at 12 months after PCI. Additionally, the trial aims to demonstrate the superiority of personalized DAPT compared to a standard approach with respect to a net clinical composite of all-cause death, any myocardial infarction, stroke, urgent target-vessel revascularization, or type 2 to 5 bleeding according to the Bleeding Academic Research Consortium criteria at 24-months after PCI.

SUMMARY

The PARTHENOPE trial is the largest randomized trial investigating the efficacy and safety of a polymer-free DES with a reservoir technology for drug-release and the first trial evaluating a personalized duration of DAPT based on the DAPT score. The study results will provide novel insights into the optimizing the use of drug-eluting stents and DAPT in patients undergoing PCI.

Evolution of Coronary Stent Platforms: A Brief Overview of Currently Used Drug-Eluting Stents

Cardiovascular disease, including ischemic heart disease, is the leading cause of death worldwide, and percutaneous coronary interventions (PCIs) have been demonstrated to improve the prognosis of these patients on top of optimal medical therapy. PCIs have evolved from plain old balloon angioplasty to coronary stent implantation at the end of the last century. There has been a constant technical and scientific improvement in stent technology from bare metal stents to the era of drug-eluting stents (DESs) to overcome clinical challenges such as target lesion failure related to in-stent restenosis or stent thrombosis. A better understanding of the underlying mechanisms of these adverse events has led DESs to evolve from first-generation DESs to thinner and ultrathin third-generation DESs with improved polymer biocompatibility that seems to have reached a peak in efficiency. This review aims to provide a brief historical overview of the evolution of coronary DES platforms and an update on clinical studies and major characteristics of the most currently used DESs.

Impact of premature coronary artery disease on adverse event risk following first percutaneous coronary intervention

Objectives

We assessed differences in risk profile and 3-year outcome between patients undergoing percutaneous coronary intervention (PCI) for premature and non-premature coronary artery disease (CAD).

Background

The prevalence of CAD increases with age, yet some individuals develop obstructive CAD at younger age.

Methods

Among participants in four randomized all-comers PCI trials, without previous coronary revascularization or myocardial infarction (MI), we compared patients with premature (men <50 years; women <55 years) and non-premature CAD. Various clinical endpoints were assessed, including multivariate analyses.

Results

Of 6,171 patients, 887 (14.4%) suffered from premature CAD. These patients had fewer risk factors than patients with non-premature CAD, but were more often smokers (60.7% vs. 26.4%) and overweight (76.2% vs. 69.8%). In addition, premature CAD patients presented more often with ST-segment elevation MI and underwent less often treatment of multiple vessels, and calcified or bifurcated lesions. Furthermore, premature CAD patients had a lower all-cause mortality risk (adj.HR: 0.23, 95%-CI: 0.10-0.52; p < 0.001), but target vessel revascularization (adj.HR: 1.63, 95%-CI: 1.18-2.26; p = 0.003) and definite stent thrombosis risks (adj.HR: 2.24, 95%-CI: 1.06-4.72; p = 0.034) were higher. MACE rates showed no statistically significant difference (6.6% vs. 9.4%; adj.HR: 0.86, 95%-CI: 0.65-1.16; p = 0.33).

Conclusions

About one out of seven PCI patients was treated for premature CAD. These patients had less complex risk profiles than patients with non-premature CAD; yet, their risk of repeated revascularization and stent thrombosis was higher. As lifetime event risk of patients with premature CAD is known to be particularly high, further efforts should be made to improve modifiable risk factors such as smoking and overweight.

TWENTE trials

(TWENTE I, clinicaltrials.gov: NCT01066650), DUTCH PEERS (TWENTE II, NCT01331707), BIO-RESORT (TWENTE III, NCT01674803), and BIONYX (TWENTE IV, NCT02508714).

DES Strut Thickness and Clinical Outcomes After CTO Recanalization: Insights From LATAM CTO Registry

BACKGROUND

Ultra-thin strut drug-eluting stent (UTS-DES) may improve outcomes after percutaneous coronary intervention (PCI) but have received limited study in chronic total occlusion (CTO) PCI.

AIMS

To compare of 1-year incidence of major adverse cardiac events (MACE) between patients who underwent CTO PCI with ultrathin (≤ 75 μm) versus thin (>75 μm) strut DES in the LATAM CTO registry.

METHODS

Patients were considered for inclusion only if successful CTO PCI was performed and when only one type of stent strut thickness (ultrathin or thin) was used. A propensity score matching (PSM) was computed to produce similar groups in relation to clinical and procedural characteristics.

RESULTS

Between January 2015 and January 2020, 2092 patients underwent CTO PCI, of whom 1466 were included in the present analysis (475 in the ultra-thin and 991 in the thin strut DES). In unadjusted analysis the UTS-DES group had lower rate of MACE (HR: 0.63 95 % CI 0.42 to 0.94, p = 0.04) and repeat revascularizations (HR: 0.50 95 % CI 0.31 to 0.81, p = 0.02) at 1-year follow-up. After adjustment for confounding factors in a Cox regression model there was no difference in 1-year incidence of MACE between groups (HR: 1.15 95 % CI 0.41 to 2.97, p = 0.85). On PSM of 686 patients (343 in each group) the 1-year incidence of MACE (HR 0.68 95 % CI 0.37-1.23; P = 0.22) and individual components of MACE did not differ between groups.

CONCLUSIONS

One-year clinical outcomes after CTO PCI were similar with ultrathin and thin strut DES.

Risk of bleeding after percutaneous coronary intervention and its impact on further adverse events in clinical trial participants with comorbid peripheral arterial disease

BACKGROUND

Both patients with obstructive coronary artery disease (CAD) and patients with peripheral arterial disease (PADs) have an increased bleeding risk. Information is scarce on bleeding in CAD patients, treated with percutaneous coronary intervention (PCI), who have comorbid PADs. We assessed whether PCI patients with PADs have a higher bleeding risk than PCI patients without PADs. Furthermore, in PCI patients with PADs we evaluated the extent by which bleeding increased the risk of further adverse events.

METHODS

Three-year pooled patient-level data of two randomized PCI trials (BIO-RESORT, BIONYX) with drug-eluting stents were analyzed to assess mortality and the composite endpoint major adverse cardiac events (MACE: all-cause mortality, any myocardial infarction, emergent coronary artery bypass surgery, or target lesion revascularization).

RESULTS

Among 5989 all-comer patients, followed for 3 years, bleeding occurred in 7.7% (34/440) with comorbid PADs and 5.0% (279/5549) without PADs (HR: 1.59, 95%CI: 1.11-2.23, p = 0.010). Of all PADs patients, those with a bleeding had significantly higher rates of all-cause mortality (HR: 4.70, 95%CI: 2.37-9.33, p < 0.001) and MACE (HR: 2.39, 95%CI: 1.23-4.31, p = 0.003). Furthermore, PADs patients with a bleeding were older (74.4 ± 6.9 vs. 67.4 ± 9.5, p < 0.001). After correction for age and other potential confounders, bleeding remained independently associated with all-cause mortality (adj.HR: 2.97, 95%CI: 1.37-6.43, p = 0.006) while the relation of bleeding with MACE became borderline non-significant (adj.HR: 1.85, 95%CI: 0.97-3.55, p = 0.06).

CONCLUSION

PCI patients with PADs had a higher bleeding risk than PCI patients without PADs. In PADs patients, bleeding was associated with all-cause mortality, even after adjustment for potential confounders.

Biodegradable polymer everolimus-eluting stents versus contemporary drug-eluting stents: a systematic review and meta‑analysis

In spite of similar efficacy and safety in pilot studies, compared with the contemporary durable polymer drug-eluting stent (DP-DES), the bioabsorbable polymer drug-eluting stent (BP-DES) may be more superior in promoting blood vessel healing. We sought to compare the safety and efficacy of everolimus-eluting BP-DES (BP-EES) with contemporary DP-DES through a meta-analysis. We performed this meta-analysis to provide further evidence of the safety and efficacy of BP-EES. Medline, Embase and the Cochrane library databases were searched for randomized controlled trials comparing clinical efficacy and safety of BP-EES versus contemporary DP-DES. Fifteen RCTs with a total of 15,572 patients were selected. The rate of MACE was 9.4% in patients receiving BP-EES and 7.3% receiving DP-EES (RR 1.13, 95% CI 0.99-1.29, p = 0.05; I² = 46%). TLF and MI were also similar in both groups. Based on the available data, this review demonstrates that BP-EES displays a clinically comparable efficacy and safety profile to that of contemporary DP-DES at years of follow-up in patients undergoing PCI.

Durable polymer versus biodegradable polymer drug-eluting stents in patients with acute coronary syndrome undergoing complex percutaneous coronary intervention: a post hoc analysis of the HOST-REDUCE-POLYTECH-ACS trial

BACKGROUND

Comparative data of durable polymer (DP) versus biodegradable polymer (BP) drug-eluting stents (DES) are limited in patients presenting with acute coronary syndrome (ACS) undergoing complex percutaneous coronary intervention (PCI).

AIMS

We sought to evaluate the efficacy and safety of DP-DES and BP-DES in ACS patients receiving complex PCI.

METHODS

This study was a post hoc analysis of the HOST-REDUCE-POLYTECH-ACS trial. ACS patients were randomly assigned 1:1 to DP-DES or BP-DES in the HOST-REDUCE-POLYTECH-ACS trial. Complex PCI was defined as having at least 1 of the following features: ≥3 stents implanted, ≥3 lesions treated, total stent length ≥60 mm, bifurcation PCI with 2 stents, left main PCI, or heavy calcification. Patient-oriented (POCO, a composite of all-cause death, non-fatal myocardial infarction, and any repeat revascularisation) and device-oriented composite outcomes (DOCO, a composite of cardiac death, target vessel myocardial infarction, or target lesion revascularisation) were evaluated at 12 months.

RESULTS

Among 3,301 patients for whom full procedural data were available, 1,140 patients received complex PCI. Complex PCI was associated with higher risks of POCO and DOCO. The risks of POCO were comparable between DP-DES and BP-DES in both the complex (HR 0.87, 95% confidence interval [CI]: 0.57-1.33; p=0.522) and non-complex (HR 0.83, 95% CI: 0.56-1.24; p=0.368; p for interaction=0.884) PCI groups. DOCO was also not significantly different between DP-DES and BP-DES in both the complex (HR 0.74, 95% CI: 0.43-1.27; p=0.278) and non-complex (HR 0.67, 95% CI: 0.38-1.19; p=0.175; p for interaction=0.814) PCI groups.

CONCLUSIONS

In ACS patients, DP-DES and BP-DES showed similar clinical outcomes irrespective of PCI complexity.

Final 5‐Year Report of the Randomized BIO‐RESORT Trial Comparing 3 Contemporary Drug‐Eluting Stents in All‐Comers

Background

In a previous trial, higher 5‐year mortality was observed following treatment with biodegradable polymer Orsiro sirolimus‐eluting stents (SES). We assessed 5‐year safety and efficacy of all‐comers as well as patients with diabetes treated with SES or Synergy everolimus‐eluting stents (EES) versus durable polymer Resolute Integrity zotarolimus‐eluting stents (ZES).

Methods and Results

The randomized BIO‐RESORT (Comparison of Biodegradable Polymer and Durable Polymer Drug‐Eluting Stents in an All Comers Population) trial enrolled 3514 all‐comer patients at 4 Dutch cardiac centers. Patients aged ≥18 years who required percutaneous coronary intervention were eligible. Participants were stratified for diabetes and randomized to treatment with SES, EES, or ZES (1:1:1). The main end point was target vessel failure (cardiac mortality, target vessel myocardial infarction, or target vessel revascularization). Five‐year follow‐up was available in 3183 of 3514 (90.6%) patients. The main end point target vessel failure occurred in 142 of 1169 (12.7%) patients treated with SES, 130 of 1172 (11.6%) treated with EES, versus 157 of 1173 (14.1%) treated with ZES (hazard ratio [HR], 0.89 [95% CI, 0.71–1.12], P log‐rank =0.31; and HR, 0.82 [95% CI, 0.65–1.04], P log‐rank =0.10, respectively). Individual components of target vessel failure showed no significant between‐stent difference. Very late definite stent thrombosis rates were low and similar (SES, 1.1%; EES, 0.6%; ZES, 0.9%). In patients with diabetes, target vessel failure did not differ significantly between stent‐groups (SES, 19.8%; EES, 19.2%; versus ZES, 21.1% [ P log‐rank =0.69 and P log‐rank =0.63]).

Conclusions

Orsiro SES, Synergy EES, and Resolute Integrity ZES showed similar 5‐year outcomes of safety and efficacy, including mortality. A prespecified stent comparison in patients with diabetes also revealed no significant differences in 5‐year clinical outcomes.

Registration

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01674803.

Coronary Stenting: Reflections on a 35-Year Journey

Stenting was introduced as a therapy for coronary artery disease 35 years ago, and is currently the most commonly performed minimally invasive procedure globally. Percutaneous coronary revascularization, initially with plain old balloon angioplasty and later with stenting, has dramatically affected the outcomes of acute myocardial infarction and acute coronary syndromes. Coronary stenting is probably the most intensively studied therapy in medicine on the basis of the number of randomized clinical trials for a broad range of indications. Continuous improvements in stent materials, design, and coatings concurrent with procedural innovations have truly been awe-inspiring. The story of stenting is replete with high points and some low points, such as the initial experience with stent thrombosis and restenosis, and the more recent disappointment with bioabsorbable scaffolds. History has shown rapid growth of stent use with expansion of indications followed by contraction of some uses in response to clinical trial evidence in support of bypass surgery or medical therapy. In this review we trace the constantly evolving story of the coronary stent from the earliest experience until the present time. Undoubtedly, future iterations of stent design and materials will continue to move the stent story forward.

Ultrathin Struts Drug-Eluting Stents: A State-of-the-Art Review

New-generation drug-eluting stents (DESs) represent the standard of care for patients undergoing percutaneous coronary intervention (PCI). Recent iterations in DES technology have led to the development of newer stent platforms with a further reduction in strut thickness. This new DES class, known as ultrathin struts DESs, has struts thinner than 70 µm. The evidence base for these devices consists of observational data, large-scale meta-analyses, and randomized trials with long-term follow-up, which have been conducted to investigate the difference between ultrathin struts DESs and conventional new-generation DESs in a variety of clinical settings and lesion subsets. Ultrathin struts DESs may further improve the efficacy and safety profile of PCI by reducing the risk of target-lesion and target-vessel failures in comparison to new-generation DESs. In this article, we reviewed device characteristics and clinical data of the Orsiro (Biotronik, Bülach, Switzerland), Coroflex ISAR (B. Braun Melsungen, Germany), BioMime (Meril Life Sciences Pvt. Ltd., Gujarat, India), MiStent (MiCell Technologies, USA), and Supraflex (Sahajanand Medical Technologies, Surat, India) sirolimus-eluting stents.

An intricate interplay between stent drug dose and release rate dictates arterial restenosis

Since the introduction of percutaneous coronary intervention (PCI) for the treatment of obstructive coronary artery disease (CAD), patient outcomes have progressively improved. Drug eluting stents (DES) that employ anti-proliferative drugs to limit excess tissue growth following stent deployment have proved revolutionary. However, restenosis and a need for repeat revascularisation still occurs after DES use. Over the last few years, computational models have emerged that detail restenosis following the deployment of a bare metal stent (BMS), focusing primarily on contributions from mechanics and fluid dynamics. However, none of the existing models adequately account for spatiotemporal delivery of drug and the influence of this on the cellular processes that drive restenosis. In an attempt to fill this void, a novel continuum restenosis model coupled with spatiotemporal drug delivery is presented. Our results indicate that the severity and time-course of restenosis is critically dependent on the drug delivery strategy. Specifically, we uncover an intricate interplay between initial drug loading, drug release rate and restenosis, indicating that it is not sufficient to simply ramp-up the drug dose or prolong the time course of drug release to improve stent efficacy. Our model also shows that the level of stent over-expansion and stent design features, such as inter-strut spacing and strut thickness, influence restenosis development, in agreement with trends observed in experimental and clinical studies. Moreover, other critical aspects of the model which dictate restenosis, including the drug binding site density are investigated, where comparisons are made between approaches which assume this to be either constant or proportional to the number of smooth muscle cells (SMCs). Taken together, our results highlight the necessity of incorporating these aspects of drug delivery in the pursuit of optimal DES design.

In-vivo evaluation of molybdenum as bioabsorbable stent candidate

Biodegradable stents have tremendous theoretical potential as an alternative to bare metal stents and drug-eluting stents for the treatment of obstructive coronary artery disease. Any bioresorbable or biodegradable scaffold material needs to possess optimal mechanical properties and uniform degradation behavior that avoids local and systemic toxicity. Recently, molybdenum (Mo) has been investigated as a potential novel biodegradable material for this purpose. With its proven moderate degradation rate and excellent mechanical properties, Mo may represent an ideal source material for clinical cardiac and vascular applications. The present study was performed to evaluate the mechanical performance of metallic Mo in vitro and the biodegradation properties in vivo. The results demonstrated favorable mechanical behavior and a uniform degradation profile as desired for a new generation ultra-thin degradable endovascular stent material. Moreover, Mo implants in mouse arteries avoided the typical cellular response that contributes to restenosis. There was minimal neointimal hyperplasia over 6 months, an absence of excessive smooth muscle cell (SMC) proliferation or inflammation near the implant, and avoidance of significant harm to regenerating endothelial cells (EC). Qualitative inspection of kidney sections showed a potentially pathological remodeling of kidney Bowman's capsule and glomeruli, indicative of impaired filtering function and development of kidney disease, although quantifications of these morphological changes were not statistically significant. Together, the results suggest that the products of Mo corrosion may exert beneficial or inert effects on the activities of inflammatory and arterial cells, while exerting potentially toxic effects in the kidneys that warrant further investigation.

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Mo implants in mouse arteries avoided neointimal hyperplasia over 6 months.

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Quantification of CD31-labeled arterial sections showed an avoidance of significant harm to regenerating endothelial cells for the Mo implants.

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Qualitative inspection of kidney sections showed a potential pathological remodeling, indicative of possible impaired filtering function.

Recent Advances in Stent Technology: Do They Reduce Cardiovascular Events?

PURPOSE OF REVIEW

Drug-eluting stents are used in nearly all cases of percutaneous coronary revascularization and have been shown to be superior to balloon angioplasty or bare metal stents. The designs of these stents are continually evolving to maximize efficacy and safety.

RECENT FINDINGS

This review outlines the important components of a drug-eluting stent and highlights the changes in stent design that have led to the optimization of clinical outcomes. Most stents used in contemporary times are thin strut, durable polymer drug-eluting stents (DES) that elute either everolimus or zotarolimus. Newer DES designs incorporating bioresorbable polymers or ultrathin struts have shown encouraging safety and efficacy profiles. DES are essential for the management of patients with obstructive coronary artery disease and are used in most coronary interventions. Changes in stent designs over the past 30 years reflect the ongoing need to address the limitations of earlier stents aimed to improve patient outcomes.

Prediction of All-Cause Mortality Following Percutaneous Coronary Intervention in Bifurcation Lesions Using Machine Learning Algorithms

Stratifying prognosis following coronary bifurcation percutaneous coronary intervention (PCI) is an unmet clinical need that may be fulfilled through the adoption of machine learning (ML) algorithms to refine outcome predictions. We sought to develop an ML-based risk stratification model built on clinical, anatomical, and procedural features to predict all-cause mortality following contemporary bifurcation PCI. Multiple ML models to predict all-cause mortality were tested on a cohort of 2393 patients (training, n = 1795; internal validation, n = 598) undergoing bifurcation PCI with contemporary stents from the real-world RAIN registry. Twenty-five commonly available patient-/lesion-related features were selected to train ML models. The best model was validated in an external cohort of 1701 patients undergoing bifurcation PCI from the DUTCH PEERS and BIO-RESORT trial cohorts. At ROC curves, the AUC for the prediction of 2-year mortality was 0.79 (0.74–0.83) in the overall population, 0.74 (0.62–0.85) at internal validation and 0.71 (0.62–0.79) at external validation. Performance at risk ranking analysis, k-center cross-validation, and continual learning confirmed the generalizability of the models, also available as an online interface. The RAIN-ML prediction model represents the first tool combining clinical, anatomical, and procedural features to predict all-cause mortality among patients undergoing contemporary bifurcation PCI with reliable performance.

Comparison of biodegradable and durable polymer drug-eluting stents in acute coronary syndrome: a meta-analysis

OBJECTIVE

To compare the safety and effectiveness between biodegradable polymer drug-eluting stents (BP-DES) and durable polymer drug-eluting stents (DP-DES) in patients with acute coronary syndrome (ACS).

DESIGN

Meta-analysis of randomised controlled trials (RCTs).

PRIMARY AND SECONDARY OUTCOME MEASURES

Major adverse cardiovascular events (MACEs) were considered the primary endpoint. Efficacy endpoints included target vessel revascularisation (TVR) and target lesion revascularisation (TLR). Safety endpoints included all-cause death, cardiac death, target vessel myocardial infarction and stent thrombosis (ST).

METHODS

We searched PubMed, Medline, Embase and the Cochrane Controlled Register of Trials for comparative studies of BP-DES and DP-DES in patients with ACS from January 2000 to July 2021. Statistical pooling was performed to estimate incidence using a random-effects model with generic inverse-variance weighting. Risk estimates were computed with 95% CIs.

RESULTS

Eight articles with seven RCTs that compared BP-DES and DP-DES in patients with ACS were identified and included in the qualitative and quantitative analyses. There was no difference in the baseline characteristics, except for the number of smoking patients (OR: 1.13, 95% CI 1.03 to 1.24; p=0.008, I²=29%), which was significantly lower in the BP-DES group. The meta-analysis demonstrated that MACEs, efficacy endpoints and safety endpoints were similar between the groups at 1 year. However, the incidence of total ST was significantly different between the BP-DES and DP-DES groups in the follow-up period (p=0.0001). Further analysis showed a statistically significant difference in MACEs (OR: 0.71, 95% CI 0.57 to 0.88; p=0.002, I²=0 %), TLR (OR: 0.71, 95% CI 0.51 to 1.01; p=0.05, I²=0%), TVR (OR: 0.70, 95% CI 0.52 to 0.94; p=0.002, I²=15%), total ST incidence (OR: 0.59, 95% CI 0.46 to 0.77; p=0.0001, I²=48%) and ST incidence (OR: 0.63, 95% CI 0.47 to 0.85; p=0.002, I²=0%) over 2 years.

CONCLUSION

This meta-analysis revealed that both stent types demonstrated excellent safety and efficacy profiles at 12 months. However, a slight increase in MACEs, TLR, TVR and ST incidence was observed in the DP-DES group over the 2-year follow-up period, suggesting that BP-DES may be more favourable when treating patients with ACS.

TRIAL REGISTRATION NUMBER

NCT00389220.

Impact of Left Ventricular Ejection Fraction on Procedural and Long-Term Outcomes of Bifurcation Percutaneous Coronary Intervention

The association of left ventricular ejection fraction (LVEF) with procedural and long-term outcomes after state-of-the-art percutaneous coronary intervention (PCI) of bifurcation lesions remains unsettled. A total of 5,333 patients who underwent contemporary coronary bifurcation PCI were included in the intercontinental retrospective combined insights from the unified RAIN (veRy thin stents for patients with left mAIn or bifurcatioN in real life) and COBIS (COronary BIfurcation Stenting) III bifurcation registries. Of 5,003 patients (93.8%) with known baseline LVEF, 244 (4.9%) had LVEF <40% (bifurcation with reduced ejection fraction [BIFrEF] group), 430 (8.6%) had LVEF 40% to 49% (bifurcation with mildly reduced ejection fraction [BIFmEF] group) and 4,329 (86.5%) had ejection fraction (EF) ≥50% (bifurcation with preserved ejection fraction [BIFpEF] group). The primary end point was the Kaplan-Meier estimate of major adverse cardiac events (MACEs) (a composite of all-cause death, myocardial infarction, and target vessel revascularization). Patients with BIFrEF had a more complex clinical profile and coronary anatomy. No difference in procedural (30 days) MACE was observed across EF categories, also after adjustment for in-study outcome predictors (BIFrEF vs BIFmEF: adjusted hazard ratio [adj-HR] 1.39, 95% confidence interval [CI] 0.37 to 5.21, p = 0.626; BIFrEF vs BIFpEF: adj-HR 1.11, 95% CI 0.25 to 2.87, p = 0.883; BIFmEF vs BIFpEF: adj-HR 0.81, 95% CI 0.29 to 2.27, p = 0.683). BIFrEF was independently associated with long-term MACE (median follow-up 21 months, interquartile range 10 to 21 months) than both BIFmEF (adj-HR 2.20, 95% CI 1.41 to 3.41, p <0.001) and BIFpEF (adj-HR 1.91, 95% CI 1.41 to 2.60, p <0.001) groups, although no difference was observed between BIFmEF and BIFpEF groups (adj-HR 0.87, 95% CI 0.61 to 1.24, p = 0.449). In conclusion, in patients who underwent PCI of a coronary bifurcation lesion according to contemporary clinical practice, reduced LVEF (<40%), although a strong predictor of long-term MACEs, does not affect procedural outcomes.

Osstem Cardiotec Centum Stent Versus Xience Alpine Stent for De Novo Coronary Artery Lesion: A Multicenter, Randomized, Parallel-Designed, Single Blind Test

BACKGROUND AND OBJECTIVES

To compare the safety and efficacy of a new everolimus-eluting stent with an abluminal-coated biodegradable polymer (Osstem Cardiotec Centum) with those of the Xience Alpine stent (Xience).

METHODS

This randomized, prospective, multicenter, parallel-designed, single-blind trial was conducted among patients with myocardial ischemia undergoing percutaneous coronary intervention (PCI) from 21st September 2018 until 3rd July 2020. The primary efficacy endpoint was in-segment late lumen loss (LLL) at 270 days after the procedure and the primary safety endpoints were major adverse cardiac events (MACE), composite of cardiac death, myocardial infarction, and target lesion revascularization.

RESULTS

We enrolled 121 patients and analyzed 113 patients who finished 270 days of follow-up for the primary efficacy endpoint. The mean age of the participants was 66.8 years. As for the primary efficacy endpoint, LLL of the Osstem Cardiotec Centum group was 0.09±0.13 mm and that of the Xience group was 0.12±0.14 mm (upper limit of 1-sided 95% confidence interval, 0.02; p for non-inferiority, 0.0084). This result demonstrates the non-inferiority of the Osstem Cardiotec Centum. As for the primary safety endpoint, MACE occurred in one patient (1.59% of the Xience group). Meanwhile, no MACE occurred in the Osstem Cardiotec Centum group.

CONCLUSIONS

The Osstem Cardiotec Centum is non-inferior to the Xience Alpine® stent and is confirmed to be safe. It could be safely and effectively applied to patients with coronary artery disease undergoing PCI.

Long-Term Clinical Outcomes Between Biodegradable and Durable Polymer Drug-Eluting Stents: A Nationwide Cohort Study

Background

Despite the theoretical benefits of biodegradable polymer drug-eluting stents (BP-DES), clinical benefits of BP-DES over durable polymer DES (DP-DES) have not been clearly demonstrated. Using data from a large-volume nationwide cohort, we compared long-term clinical outcomes between BP-DES- and DP-DES-treated patients.

Methods

A retrospective cohort study that enrolled all patients who underwent percutaneous coronary intervention (PCI) with new-generation DES between 2010 and 2016 in Korea was conducted by using the National Health Insurance Service database. The outcomes of interest were all-cause death, cardiovascular death, and myocardial infarction (MI).

Results

A total of 127,731 patients treated with new-generation DES with thin struts (<90 μm) were enrolled for this analysis. After stabilized inverse probability of treatment weighting, the incidence of all-cause death was significantly lower in patients treated with BP-DES (n = 19,521) at 5 years after PCI (11.3 vs. 13.0% in those treated with DP-DES [n = 108,067], hazard ratio [HR] 0.92, 95% confidence interval [CI], 0.88–0.96, p < 0.001), while showing no statistically significant difference at 2 years after PCI (5.7 vs. 6.0%, respectively, HR 0.95, 95% CI, 0.89–1.01, p = 0.238). Similarly, use of BP-DES was associated with a lower incidence of cardiovascular death (7.4 vs. 9.6% in those treated with DP-DES, HR 0.82, 95% CI, 0.77–0.87, p < 0.001), and MI (7.4 vs. 8.7%, respectively, HR 0.90, 95% CI, 0.86–0.94, p = 0.006) at 5 years after PCI. There was no statistically significant difference of cardiovascular death (4.6 vs. 4.9%, respectively, HR 0.93, 95% CI, 0.85–1.01, p = 0.120) and MI (5.0 vs. 5.1%, respectively, HR 0.98, 95% CI, 0.92–1.05, p = 0.461) at 2 years after PCI.

Conclusions

Implantation of BP-DES was associated with a lower risk of all-cause death, cardiovascular death, and MI compared with DP-DES implantation. This difference was clearly apparent at 5 years after DES implantation.

Clinical Trial Registration

ClinicalTrial.gov, NCT04715594.

Comparison of Contemporary Drug-Eluting Stents in Patients Undergoing Complex High-Risk Indicated Procedures

BACKGROUND

Limited data are available on the relative performances of diverse contemporary drug-eluting stents (DES) in patients undergoing complex high-risk indicated procedures (CHIP).

OBJECTIVES

The purpose of this study was to evaluate the comparative effectiveness of contemporary second-generation DES for CHIP patients in "real-world" settings.

METHODS

Of 28,843 patients enrolled in the IRIS-DES registry, a total of 6,645 patients with CHIP characteristics who received 5 different types of contemporary DES were finally included: 3,752 with cobalt-chromium everolimus-eluting stents (CoCr-EES), 1,258 with Resolute zotarolimus-eluting stents (Re-ZES), 864 with platinum-chromium EES (PtCr-EES), 437 with ultrathin strut biodegradable-polymer sirolimus-eluting stents (UT-SES), and 334 with bioresorbable polymer SES (BP-SES). The primary outcome was target-vessel failure (a composite of cardiac death, target-vessel myocardial infarction, and target-vessel revascularization) at 12 months.

RESULTS

At 12 months, the rate of target-vessel failure was highest in the CoCr-EES (7.1%) group; intermediate in the Re-ZES (5.0%), PtCr-EES (4.6%), and BP-SES (4.2%) groups; and lowest in the UT-SES (3.8%) group (overall long-rank P = 0.001). In multiple-treatment propensity-score analysis, the adjusted hazard ratios (HRs) for target-vessel failure were significantly lower in the Re-ZES (HR: 0.71; 95% confidence interval [CI]: 0.52-0.97), the UT-SES (HR: 0.52; 95% CI: 0.29-0.95), and BP-SES (HR: 0.33; 95% CI: 0.16-0.70) groups than in the CoCr-EES group (referent).

CONCLUSIONS

In this contemporary PCI registry, we observed the differential risks of target-vessel failure according to various types of contemporary DES in patients with CHIP characteristics. However, owing to inherent selection bias, the results should be considered hypothesis-generating, highlighting the need for further randomized trials. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133).

Temporal trends in clinical outcomes after percutaneous coronary intervention: a systematic review of 66,327 patients from 25 all-comers trials

BACKGROUND

With the improvements of percutaneous coronary intervention (PCI) technology and post-PCI patient management, several registry studies reported temporal trends in post-PCI clinical outcomes. However, their results are inconclusive, potentially reflecting region-specific trends, based on site-reported events without external validity.

AIMS

This study aimed to investigate temporal trends in post-PCI clinical outcomes in all-comers randomised controlled trials (RCTs) involving coronary stents.

METHODS

We performed a systematic review identifying RCTs comparing a clinical outcome as a primary endpoint among different coronary stents with an all-comers design and independent clinical event adjudication, extracting the study start year, patient baseline characteristics, and one- and five-year clinical outcomes. Temporal trends in clinical outcomes (cardiac death, myocardial infarction [MI], target lesion revascularisation [TLR], stent thrombosis [ST]) were assessed using random-effects meta-regression analyses, estimating the relationship between clinical outcomes and study start year.

RESULTS

Overall, 25 all-comers trials (51 device arms, 66,327 patients) conducted between 2003 and 2018 fulfilled the eligibility criteria. Random-effects meta-regression analysis revealed significant decreasing trends in one- and five-year cardiac death, one-year TLR, and five-year ST incidences (relative risk per 10-year increase: 0.69 [0.51-0.92], 0.66 [0.44-0.98], 0.60 [0.41-0.88], and 0.18 [0.07-0.44], respectively). There was no significant trend in myocardial infarction incidences.

CONCLUSIONS

This is the first attempt to clarify and quantify the temporal trends of post-PCI outcome incidence. The 15-year improvements in PCI therapy and post-therapeutic patient management are associated with reduced incidences of cardiac death and PCI-related adverse events.

Consequences of Inaccurate Assumptions in Coronary Stent Noninferiority Trials: A Systematic Review and Meta-analysis

IMPORTANCE

The outcome and interpretation of noninferiority trials depend on the magnitude of the noninferiority margin and whether a relative or absolute noninferiority margin is used and may be affected by imprecision in event rate estimation.

OBJECTIVE

To assess the consequence of imprecise event rate estimations on interpretation of peer-reviewed randomized clinical trials.

DATA SOURCES

PubMed/MEDLINE was searched for articles published between January 1, 2015, and April 30, 2021.

STUDY SELECTION

Noninferiority randomized clinical trials of coronary stents published in selected journals with clinical events as the primary end point.

DATA EXTRACTION AND SYNTHESIS

Two reviewers (M.S. and F.V.) independently extracted data on trial characteristics, noninferiority assumptions, primary end point clinical outcomes, and study conclusions. Overestimation or underestimation of the control event rate was evaluated by dividing the assumed control event rate by the observed control event rate. For noninferiority end points with absolute margins, the assumed corresponding relative margin was defined as the ratio of the absolute margin and the assumed event rate, and the observed corresponding relative margin as the ratio between the absolute margin and the observed event rate in the control arm. Noninferiority comparisons with absolute margins were reanalyzed using the assumed corresponding relative margin and the Farrington-Manning score test for relative risk.

MAIN OUTCOMES AND MEASURES

Overestimation or underestimation, assumed and observed corresponding relative margins, and relative reanalysis of the primary end points of trials with absolute margins.

RESULTS

A total of 106 989 patients from 58 trials were included. The event rate in the control arms was overestimated by a median (IQR) of 28% (2%-74%). Most noninferiority trials used absolute rather than relative margins (55 of 58 trials [94.8%]). Owing to overestimation, absolute noninferiority margins became more permissive than originally assumed (median [IQR] of observed relative noninferiority margin, 1.62 [1.50-1.80] vs assumed relative noninferiority margin, 1.47 [1.39-1.55]; P < .001). Among trial comparisons that met noninferiority with an absolute noninferiority margin, 17 of 50 trials (34.0%) would not have met noninferiority with a corresponding assumed relative noninferiority margin.

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis, assumed event rates were often overestimated in noninferiority coronary stent trials. Because most of these trials use absolute margins to define noninferiority, such overestimation results in excessively permissive relative noninferiority margins.

PRospective Observational Registry Evaluating the Safety and Effectivenessof Orsiro Stent in Chilean Patients - ROSES Registry

BACKGROUND

There is little information on the performance of the new generation of stents with bioabsorbable polymers in the Latin American population. This registry aimed to further validate the safety and efficacy of the Orsiro bioresorbable-polymer sirolimus-eluting stent (BPSES) in unselected patients undergoing percutaneous coronary intervention (PCI) in Chilean centers.

METHODS

We prospectively enrolled patients undergoing PCI with BPSES in 6 Chilean centers. The primary endpoint was defined as the composite of cardiac death, target vessel-related myocardial infarction (MI), and clinically driven target lesion revascularization at 1-year follow-up.

RESULTS

From April 2017 to February 2019, 520 patients were enrolled in the registry, more frequently male (74.6%), with a mean age of 62.7 ± 10.8 years and a high prevalence of diabetes (40.2%). The clinical presentation was stable angina in 41.1% (n = 214), acute MI in 52.5% (n = 167 [32.1%] ST-elevation MI and n = 106 [20.4%] non-ST-elevation MI), and unstable angina in 6.3% (n = 33). Of 610 treated lesions, 425 (69.7%) were American College of Cardiology/American Heart Association type B or C lesions. Device and procedural success were achieved in 99.4% and 98.7% of the patients, respectively. The primary endpoint of the study occurred in 4%, primarily driven by cardiac death.

CONCLUSIONS

The results of the ROSES multicenter registry indicated good clinical outcomes of BPSES Orsiro in all-comers Latin Americann patients undergoing PCI, despite the high-risk patients and treated lesions.

Effect of Crack Patterns in Calcified Plaque on Lumen Area after Stenting for a Severe Calcified Coronary Artery (from the Optical Frequency Domain Imaging-Guided Percutaneous Coronary Artery Intervention for Calcified Lesion Registry)

Background

Severely calcified coronary artery stenting remains a challenge due to stent thrombosis, target vessel failure, and higher mortality. Moreover, optimal vessel preparation for calcified plaque with a crack formation pattern has not been established yet. We aimed to identify the effect of crack formation in calcified plaque in the coronary artery on the lumen area after stenting.

Materials and Methods

We evaluated 50 consecutive patients undergoing drug-eluting stent implantation for severely calcified lesions by using optical frequency domain imaging (OFDI) (54 lesions); we analyzed OFDI image slices every 3 mm and evaluated the segments of 242 images in those who had the arc of calcium more than 180°. Crack formation in calcified plaque was classified into three types: type 0, no cracks; type 1, no dissection between calcified plaque and vessel wall; and type 2, any dissection between calcified plaque and vessel wall.

Results

Type 2 had a significantly higher area expansion ratio between preballooning and poststenting (type 0, 196% (interquartile range (IQR), 163–244); type 1, 210% (IQR, 174–244); type 2, 237% (IQR, 203–294)).

Conclusions

The dissection between calcified plaque and vessel wall was a significant factor affecting lumen area expansion after stenting.

Drug-eluting stents for the treatment of coronary artery disease: A review of recent advances

INTRODUCTION

Percutaneous coronary intervention is a widely used procedure for the treatment of coronary artery disease to relieve narrowing or occlusion and improve blood supply. Although only balloon angioplasty was performed in the early period, coronary stents were developed later and coronary drug-eluting stents were introduced to decrease in-stent restenosis, which is related to the proliferation and migration of vascular smooth muscle cells.

AREAS COVERED

The drug-eluting stents are composed of a metallic or polymeric platform, specific drug, and polymers or coating for drug release. In this article, the recent advances in drug-eluting stent technologies for the treatment of coronary artery disease and adjunctive antiplatelet therapy after drug-eluting stent implantation will be reviewed.

EXPERT OPINION

The need for further advances in drug-eluting stents or fully bioresorbable coronary scaffolds still exists to improve patient survival or clinical outcomes. The use for different actions or of combinations of drugs with several actions can be potential. Technological refinement and progress in manufacturing to improve mechanical integrity are needed, particularly for fully bioresorbable scaffolds. For antiplatelet therapy after stenting, clinical bleeding reduction strategies, such as a shortened duration of dual-antiplatelet therapy, are in progress.

A Narrative Review of Ultrathin-strut Drug-eluting Stents: The Thinner the Better?

Second-generation drug-eluting stents (DES) are considered standard of care for revascularization of patients undergoing percutaneous coronary intervention. Besides the polymer and antiproliferative drug used, the metallic backbone of DES is an attractive target for further development. Ultrathin-strut DES (≤70 μm strut thickness) are more flexible, have an improved trackability and crossability compared to conventional second-generation DES. Importantly, ultrathin-strut DES reduce the risk of in-stent restenosis, thereby decreasing the risk of angiographic and clinical restenosis. In this narrative review, we will discuss the clinical outcomes of the commercially available ultrathin-strut DES.

Overcoming challenges in refining the current generation of coronary stents

INTRODUCTION

Late stent thrombosis caused by delayed vascular healing and prolonged local inflammation were major drawbacks of 1^st generation drug-eluting stents (DES). Strut design, biocompatibility of polymer, and drug-release profiles were improved in 2^nd and 3rdgeneration DES. Accordingly, the indications for percutaneous coronary intervention with DES have been expanded to more complex patients and lesions. Despite these improvements, significant barriers such as greater flexibility in the duration of dual-antiplatelet therapy (DAPT) as well as reducing long-term stent-related events remain. To achieve ideal short- and long-term results, these existing limitations need to be overcome.

AREAS COVERED

We will discuss the current limitations of coronary DES and how they might be overcome from pathological and clinical viewpoints.

EXPERT OPINION

Optimizing DAPT duration after stent implantation and prevention of in-stent neoatherosclerosis are two major issues in current DES. Overcoming these drawbacks is a prerequisite toward achieving better short- and long-term clinical outcomes. New technologies including platform design, polymer types, and anti-proliferative agent itself might lead to further improvements. Although the initial experience with bioresorbable scaffold/stents (BRS) was disappointing, positive results of clinical studies regarding novel BRS are raising expectations. Overall, further device innovation is desired for overcoming the limitations of current DES.

Differential Effects of Newer-Generation Ultrathin-Strut Versus Thicker-Strut Drug-Eluting Stents in Chronic and Acute Coronary Syndromes

OBJECTIVES

The authors sought to compare the differential effects of ultrathin-strut and thicker-strut drug-eluting stents (DES) in patients with chronic (CCS) versus acute (ACS) coronary syndromes.

BACKGROUND

Newest-generation ultrathin-strut DES reduce target lesion failure (TLF) compared with thicker-strut second-generation DES in patients undergoing percutaneous coronary intervention.

METHODS

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched for randomized controlled trials comparing newer-generation ultrathin-strut (<70 μm) versus thicker-strut (≥70 μm) DES. Patients were divided based on baseline clinical presentation (CCS versus ACS). The primary endpoint was TLF, a composite of cardiac death, target vessel myocardial infarction, or clinically indicated target lesion revascularization (TLR).

RESULTS

A total of 22,766 patients from 16 randomized controlled trials were included, of which 9 trials reported TLF rates in ACS patients. At a mean follow-up of 12.2 months, the risk of TLF was lower among patients treated with ultrathin-strut compared with thicker-strut DES (risk ratio [RR]: 0.85; 95% CI: 0.75-0.95; P = 0.006). The difference was driven by a lower risk of clinically-indicated TLR (RR: 0.75; 95% CI: 0.63-0.89; P < 0.001) among patients treated with ultrathin-strut DES. The treatment effect was consistent between patients presenting with CCS and ACS (relative RR: 0.97; 95% CI: 0.73-1.31; P for interaction = 0.854). In patients with ST-segment elevation myocardial infarction, TLF risk was lower among those treated with ultrathin- compared with thicker-strut DES (RR: 0.74; 95% CI: 0.54-0.99; P = 0.049).

CONCLUSIONS

Ultrathin-strut DES reduce the risk of TLF compared with thicker-strut second-generation DES in patients undergoing percutaneous coronary intervention, a difference caused by a lower risk of ischemia-driven TLR. The treatment effect was consistent among patients with CCS and ACS.

Individual patient data analysis of the BIOFLOW study program comparing safety and efficacy of a bioresorbable polymer sirolimus eluting stent to a durable polymer everolimus eluting stent

OBJECTIVES

This analysis of pooled individual patient data (IPD) aimed to evaluate the safety and efficacy of a bioresorbable polymer sirolimus eluting stent system (BP-SES; Orsiro) compared to a durable polymer everolimus eluting stent system (DP-EES; Xience) in the pooled population as well as in subgroups.

METHODS

IPD with up to 12 months follow-up of the randomized controlled trials BIOFLOW-II (NCT01356888), -IV (NCT01939249), and -V (NCT02389946) as well as the all comers registry BIOFLOW-III (NCT01553526) were pooled. A total of 3,717 subjects (2,923 in BP-SES and 794 in DP-EES) with 5,328 lesions (4,225 lesions in BP-SES and 1,103 in DP-EES) were included in the IPD. The primary endpoint was target lesion failure (TLF) at 12 months follow-up. Subgroups analyzed included diabetes, age (≥65 years), gender, complex lesions (B2/C), small vessels (reference vessel diameter ≤2.75 mm), multivessel treatment, renal disease, and patients with acute coronary syndrome.

RESULTS

Overall, TLF at 12 months was significantly lower with 5.2%in the BP-SES group versus 7.6% in the DP-EES group (p = .0098). Similarly, target vessel myocardial infarction (TV-MI) was 3.1 versus 5.7% (p = .0005). The rate of stent thrombosis was similar in both groups (0.004%). By regression analysis, an independent stent effect in favor of BP-SES was observed for TLF (p = .0043) and TV-MI (p = .0364) in small vessels.

CONCLUSION

Results of this IPD analysis suggest that the BP-SES with ultrathin struts is as safe as and more efficacious than DP-EES in the overall cohort and especially in small vessels.

Impact of prediabetes and diabetes on 3-year outcome of patients treated with new-generation drug-eluting stents in two large-scale randomized clinical trials

Background

Diabetes is associated with adverse outcomes after percutaneous coronary intervention with drug-eluting stents (DES), but for prediabetes this association has not been definitely established. Furthermore, in patients with prediabetes treated with contemporary stents, bleeding data are lacking. We assessed 3-year ischemic and bleeding outcomes following treatment with new-generation DES in patients with prediabetes and diabetes as compared to normoglycemia.

Methods

For this post-hoc analysis, we pooled patient-level data of the BIO-RESORT and BIONYX stent trials which both stratified for diabetes at randomization. Both trials were multicenter studies performed in tertiary cardiac centers. Study participants were patients of whom glycemic state was known based on hemoglobin A1c, fasting plasma glucose, or medically treated diabetes. Three-year follow-up was available in 4212/4330 (97.3 %) patients. The main endpoint was target vessel failure, a composite of cardiac death, target vessel myocardial infarction, or target vessel revascularization.

Results

Baseline cardiovascular risk profiles were progressively abnormal in patients with normoglycemia, prediabetes, and diabetes. The main endpoint occurred in 54/489 patients with prediabetes (11.2 %) and 197/1488 with diabetes (13.7 %), as compared to 142/2,353 with normoglycemia (6.1 %) (HR: 1.89, 95 %-CI 1.38–2.58, p < 0.001, and HR: 2.30, 95 %-CI 1.85–2.86, p < 0.001, respectively). In patients with prediabetes, cardiac death and target vessel revascularization rates were significantly higher (HR: 2.81, 95 %-CI 1.49–5.30, p = 0.001, and HR: 1.92, 95 %-CI 1.29–2.87, p = 0.001), and in patients with diabetes all individual components of the main endpoint were significantly higher than in patients with normoglycemia (all p ≤ 0.001). Results were consistent after adjustment for confounders. Major bleeding rates were significantly higher in patients with prediabetes and diabetes, as compared to normoglycemia (3.9 % and 4.1 % vs. 2.3 %; HR:1.73, 95 %-CI 1.03–2.92, p = 0.040, and HR:1.78, 95 %-CI 1.23–2.57, p = 0.002). However, after adjustment for confounders, differences were no longer significant.

Conclusions

Not only patients with diabetes but also patients with prediabetes represent a high-risk population. After treatment with new-generation DES, both patient groups had higher risks of ischemic and bleeding events. Differences in major bleeding were mainly attributable to dissimilarities in baseline characteristics. Routine assessment of glycemic state may help to identify patients with prediabetes for intensified management of cardiovascular risk factors.

Trial registration: BIO-RESORT ClinicalTrials.gov: NCT01674803, registered 29-08-2012; BIONYX ClinicalTrials.gov: NCT02508714, registered 27-7-2015.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01405-4.

Clinical outcomes of an ultrathin-strut sirolimus-eluting stent in all-comers population: Thailand Orsiro registry

Background

Despite numerous studies supporting the outperformance of ultrathin-strut bioresorbable polymer sirolimus-eluting stent (Orsiro SES, Biotronik AG), the generalizability of the study results remains unclear in the Asian population. We sought to evaluate the clinical outcomes of the Orsiro SES in unselected Thai population.

Methods

The Thailand Orsiro registry was a prospective, open-label clinical study evaluating all patients with obstructive coronary artery disease implanted with Orsiro SES. The primary endpoint was target lesion failure (TLF) at 12 months. TLF is defined as a composite of cardiac death, target vessel myocardial infarction (TVMI), emergent coronary artery bypass graft (CABG), and clinically driven target lesion revascularization (CD-TLR). Patients with diabetes, small vessels (≤ 2.75 mm), chronic total occlusions (CTOs), and acute myocardial infarction (AMI) were pre-specified subgroups for statistical analysis.

Result

A total of 150 patients with 235 lesions were included in the analysis. Half of the patients (53.3%) presented with AMI, and 24% had diabetes. Among 235 lesions, 93(39.4%) were small vessels, and 24(10.2%) were chronic total occlusions. The primary endpoint, TLF at 12 months, occurred in eight patients (5.3%), predominately caused by cardiac death. By contrast, the incidences of TVMI and CD-TLR were null. The outcomes in pre-specified subgroup were not different from the overall population (all p > 0.05). One definite late stent thrombosis(0.7%) was incidentally observed during primary percutaneous coronary intervention to the non-target vessel.

Conclusion

The safety and efficacy of the ultrathin strut sirolimus-eluting stent in unselected cases are confirmed in the Thailand Orsiro registry. Despite the high proportion of pre-specified high-risk subgroups, the excellent stent performance was consistent with the overall population.

Trial Registration TCTR20190325001.

Clinical outcomes of ultrathin biodegradable polymer-coated sirolimus-eluting stents in an all-comer population: One-year results from the T-FLEX registry including high-risk subgroups

OBJECTIVE

T-Flex registry was designed to investigate the safety and clinical performance of the ultrathin (60 µm) strut biodegradable polymer-coated sirolimus-eluting stent (SES) with a unique long dual Z (LDZ) link design on a cobalt-chromium stent platform (Sahajanand Medical Technologies Pvt. Ltd., Surat, India) in a real-world all-comer population including high-risk subgroups.

METHODS

This was an observational, multicenter, single-arm, and investigator-initiated retrospective registry. A total of 1,203 patients treated with an ultrathin biodegradable polymer-coated SES, irrespective of lesion complexity, comorbidities, and acute presentation were analyzed from May 2016 to January 2017. The primary endpoint was the one-year incidence of target lesion failure (TLF), a composite of cardiac death, target-vessel myocardial infarction (TV-MI), and clinically-indicated target lesion revascularization (CI-TLR). Stent thrombosis was assessed as an additional safety endpoint.

RESULTS

At the one-year follow-up, TLF was observed in 3.8% [95% confidence interval (CI) 2.9-5.1] patients, composed of 0.6% (95% CI: 0.3-1.3) cardiac death, 1.3% (95% CI: 0.8-2.2) TV-MI, and 1.9% (95% CI: 1.3-2.9) CI-TLR. In the high-risk subgroups, TLF at one-year was 6.8% (95% CI: 4.6-9.8) in patients with diabetes, 5.2% (95% CI: 3.4-8) in patients with small-vessel disease, 6.1% (95% CI: 3.9-9.6) in patients with ST-elevation myocardial infarction, and 4.5% (95% CI: 2.4-8.3) in patients with total occlusion. During follow-up, stent thrombosis was reported in 0.8% (95% CI: 0.4-1.5) patients in the overall population.

CONCLUSION

Low event rates of TLF and stent thrombosis at one-year follow-up indicate that this ultrathin biodegradable polymer-coated SES has encouraging safety and clinical performance in real-world all-comer populations as well as in high-risk subgroups.

Biodegradable- Versus Durable-Polymer Drug-Eluting Stents for STEMI: Final 2-Year Outcomes of the BIOSTEMI Trial

OBJECTIVES

The aim of this study was to investigate the safety and efficacy of biodegradable-polymer sirolimus-eluting stents (BP-SES) compared with durable-polymer everolimus-eluting stents (DP-EES) in patients with ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Primary percutaneous coronary intervention (PCI) is an effective treatment for patients with STEMI, and long-term outcomes are determined by the safety and efficacy profile of the newest generation drug-eluting stents.

METHODS

BIOSTEMI (A Comparison of an Ultrathin Strut Biodegradable Polymer Sirolimus-Eluting Stent With a Durable Polymer Everolimus-Eluting Stent for Patients With Acute ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention) was an investigator-initiated, multicenter, assessor-blind, randomized superiority trial using Bayesian methods. Patients with STEMI undergoing primary PCI within 24 h of symptom onset were randomized in a 1:1 ratio to receive BP-SES (n = 649) or DP-EES (n = 651). The primary endpoint was target lesion failure (TLF), a composite of cardiac death, target vessel myocardial reinfarction, and clinically indicated target lesion revascularization (TLR) at 2 years.

RESULTS

Between April 2016 and March 2018, 1,300 patients were included. Baseline characteristics were comparable between the 2 treatment groups. Follow-up through 2 years was complete in 1,221 patients (94%). At 2 years, TLF occurred in 33 patients (5.1%) treated with BP-SES and in 53 patients (8.1%) treated with DP-EES (rate ratio: 0.58; 95% Bayesian credible interval: 0.40 to 0.84; posterior probability of superiority = 0.998). The difference was driven by a lower incidence of clinically indicated TLR in patients treated with BP-SES compared with DP-EES (2.5% vs. 5.1%; rate ratio: 0.52; 95% Bayesian credible interval: 0.30 to 0.87; posterior probability of superiority = 0.993). There were no significant differences in rates of cardiac death, target vessel myocardial reinfarction, and definite stent thrombosis between the 2 treatment arms.

CONCLUSIONS

In patients with STEMI undergoing primary PCI, BP-SES were superior to DP-EES with respect to TLF at 2 years. The difference was driven by lower rates of ischemia-driven TLR. (A Comparison of an Ultrathin Strut Biodegradable Polymer Sirolimus-Eluting Stent With a Durable Polymer Everolimus-Eluting Stent for Patients With Acute ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention [BIOSTEMI]; NCT02579031).

Impact of stent thickness on clinical outcomes in small vessel and bifurcation lesions: a RAIN-CARDIOGROUP VII sub-study

BACKGROUND

The clinical impact of stent strut thickness in coronary bifurcation lesions in small vessels has not been assessed in a real-world population.

METHODS

All 506 patients enrolled in the RAIN study, undergoing PCI in a vessel with a diameter 2.5 mm or less were retrospectively evaluated and divided into two groups according to stent strut thickness: 74 μm (n = 206) versus 81 μm (n = 300); 87.1% of the lesions involved bifurcations. TLF [defined as a composite of myocardial infarction (MI) and target lesion revascularization (TLR)] was the primary endpoint, with MACE (a composite of death, MI and TLR), its components and stent thrombosis the secondary endpoint.

RESULTS

After 16 (14-18) months, a lower incidence of TLF (4.3 vs. 9.8%, P = 0.026) and ST (1.0 vs. 3.0%, P = 0.042) was seen in the 74 μm group, whereas MACE occurred in 60 of 506 patients, with no statistical difference between the two groups (9.7 vs. 13.3%, P = 0.070). At multivariate analysis, chronic renal failure increased the risk of TLF while thinner strut was an independent protective factor (hazard ratio 0.51, CI 0.17-0.85, P = 0.005).

CONCLUSION

In this real-world population, patients being treated for small vessels lesions with thinner strut stents had lower rates of TLF, MI and ST.

Long-term follow-up after ultrathin vs. conventional 2nd-generation drug-eluting stents: a systematic review and meta-analysis of randomized controlled trials

AIMS

Contemporary 2nd-generation thin-strut drug-eluting stents (DES) are considered standard of care for revascularization of patients undergoing percutaneous coronary intervention. A previous meta-analysis of 10 randomized controlled trials (RCTs) with 11 658 patients demonstrated a 16% reduction in the 1-year risk of target lesion failure (TLF) with ultrathin-strut DES compared with conventional 2nd-generation thin-strut DES. Whether this benefit is sustained longer term is not known, and newer trial data may inform these relative outcomes. We therefore sought to perform an updated systematic review and meta-analysis of RCTs comparing clinical outcomes with ultrathin-strut DES (≤70 µm strut thickness) with conventional 2nd-generation thin-strut DES.

METHODS AND RESULTS

We performed a random-effects meta-analysis of all RCTs comparing ultrathin-strut DES to conventional 2nd-generation thin-strut DES. The pre-specified primary endpoint was long-term TLF, a composite of cardiac death, myocardial infarction (MI), or clinically driven target lesion revascularization (CD-TLR). Secondary endpoints included the components of TLF, stent thrombosis (ST), and all-cause death. There were 16 eligible trials in which 20 701 patients were randomized. The weighted mean follow-up duration was 2.5 years. Ultrathin-strut DES were associated with a 15% reduction in long-term TLF compared with conventional 2nd-generation thin-strut DES [relative risk (RR) 0.85, 95% confidence interval (CI) 0.76-0.96, P = 0.008] driven by a 25% reduction in CD-TLR (RR 0.75, 95% CI 0.62-0.92, P = 0.005). There were no significant differences between stent types in the risks of MI, ST, cardiac death, or all-cause mortality.

CONCLUSIONS

At a mean follow-up of 2.5 years, ultrathin-strut DES reduced the risk of TLF, driven by less CD-TLR compared with conventional 2nd-generation thin-strut DES, with similar risks of MI, ST, cardiac death, and all-cause mortality.

Long term outcomes of ultrathin versus standard thickness second-generation drug eluting stents: Meta-analysis of randomized trials

OBJECTIVE

Identify the effect of ultrathin drug eluting stents on long term outcomes in coronary artery disease.

BACKGROUND

Although second-generation drug eluting stents (DES) are superior to first-generation DES, persistence of adverse outcomes has led to continued refinement in design. Ultrathin second-generation DES have been shown to improve outcomes at 1-year follow-up. Beyond 1-year their effect remains unknown.

METHODS

PubMed, Embase and Cochrane Database were searched for randomized controlled trials that compared ultrathin (defined as <70 um) to standard thickness second-generation DES. Studies were chosen according to the PROSPERO protocol (CRD42020185374). Data from randomized controlled trials were pooled using random-effects model (Mantel-Haenszel). The primary outcome was target lesion failure (TLF) at 2 years, a composite of cardiac death, target vessel myocardial infarction, and ischemia-driven target vessel revascularization. Secondary outcomes included TLF at 3 and 5 years, the components of TLF and definite or probable stent thrombosis. Differences in outcomes between groups were presented in Forest plots as risk ratios (RR) with corresponding 95% confidence intervals (CIs) for each trial.

RESULTS

We identified 18 publications from 10 trials with14,649 patients. At 2-years there was a significant 12% reduction in TLF (RR, 0.88; 95% CI 0.78-0.99; p < 0.05) associated with the use of ultrathin DES. At 3-years, there was a significant 19% reduction in TLF with ultrathin DES (RR, 0.79; 95% CI 0.64-0.98; p < 0.05).

CONCLUSION

In patients undergoing percutaneous coronary intervention, ultrathin DES improve long term clinical outcomes.

Impact of the metal-to-artery ratio on clinical outcomes in left main and nonleft main bifurcation: insights the RAIN-CARDIOGROUP VII study (veRy thin stents for patients with left mAIn or bifurcatioN in real life)

INTRODUCTION

The impact on clinical outcomes of the metal coverage on the coronary surface (namely the metal-to-artery ratio) of currently used drug-eluting stents (DESs) has not been defined.

METHODS

All patients with a left main or bifurcation stenosis treated with percutaneous coronary intervention (PCI) using ultrathin stents (struts thinner than 81 μm) were enrolled with a prospective multicentre fashion. The rate of device-oriented endpoint [DOE, defined as a composite of target lesion revascularization (TLR) and stent thrombosis] was the primary endpoint, while its single components were the secondary ones, evaluated according to the metal-to-artery ratio.

RESULTS

After 14 ± 10.4 months 62 (7.5%) of 830 patients undergoing PCI on left main experienced a DOE without differences in the metal-to-artery ratio (14.5 ± 2.1 vs. 14.4 ± 1.9, P = 0.51). Fifty out (2.4%) of 2082 patients treated with PCI on a coronary bifurcation other than left main experienced a DOE, with a higher mean metal-to-artery ratio (15.3 ± 2.1 vs. 14.6 ± 2, P = 0.01). At multivariate analysis, together with hypertension and diabetes, the metal-to-artery ratio was an independent predictor of DOE (hazard ratio 1.7 : 1.02-1.34, P = 0.02) in nonleft main PCI. When analysed for diameter, we found a significant correlation with DOE when the stent diameter was inferior to 3.0 mm (hazard ratio 1.21: 1.06-1.38, P < 0.01, all 95% confidence interval); this result was mainly consistent for patients treated with provisional stenting. The metal-to-artery ratio does not impact on outcomes in left main PCI, both in the provisional or two-stent technique, and generally when a drug-eluting stent more than 3.5 mm in diameter is implanted. Regarding nonleft main PCI, it is independently related to DOE and TLR, especially for DES with a diameter of 3.25 mm or less.

CONCLUSION

The metal-to-artery ratio does not impact on outcomes in left main PCI, both in the provisional or two-stent technique, and generally when a drug-eluting stent more than 3.5 mm in diameter is implanted. Regarding nonleft main PCI, it is independently related to DOE and TLR, especially for DES with a diameter of 3.25 mm or less.