Intravascular Imaging-Guided Versus Coronary Angiography-Guided Complex PCI: A Meta-analysis of Randomized Controlled Trials

INTRODUCTION

Trials evaluating the role of intravascular imaging in percutaneous coronary intervention (PCI) for complex coronary artery disease have yielded mixed results. This study aimed to compare the outcomes of intravascular imaging specifically intravascular ultrasound (IVUS) with those from conventional coronary angiography in complex PCI.

METHODS

Comprehensive electronic search of MEDLINE, EMBASE, and Cochrane databases was performed until March 2023 for randomized clinical trials (RCTs) comparing intravascular imaging with coronary angiography in patients undergoing complex PCI. Complex PCI was defined per each study, and included PCI for American College of Cardiology/American Heart Association (ACC/AHA) type B2/C lesions, unprotected left main coronary artery disease, or multivessel stenting. The primary study outcome was major adverse clinical events (MACE).

RESULTS

The meta-analysis included 10 RCTs with a total of 6615 patients (3576 in the intravascular imaging group and 3039 in the coronary angiography group). The weighted mean-follow up was 28.9 months. Compared with coronary angiography, intravascular imaging reduced MACE (8% vs. 13.3%; relative risk [RR] 0.63; 95% confidence interval [CI] 0.54-0.73), cardiac death (RR 0.47; 95% CI 0.31-0.73), definite/probable stent thrombosis (RR 0.48; 95% CI 0.24-0.97), target vessel revascularization (RR 0.62; 95% CI 0.46-0.83), and target lesion revascularization (RR 0.61; 95% CI 0.47-0.79). There was no difference between both groups in all-cause death (RR 0.79; 95% CI 0.53-1.18) and myocardial infarction (RR 0.80; 95% CI 0.61-1.04).

CONCLUSION

In patients undergoing complex PCI, intravascular imaging-specifically IVUS-reduced MACE by decreasing the incidence of cardiac death, stent thrombosis, and target vessel and target lesion revascularization.

Long-term outcomes of less drug-eluting stents by the use of drug-coated balloons in de novo coronary chronic total occlusion intervention: A multicenter observational study

Background

Data on drug-coated balloons (DCB) for de novo coronary chronic total occlusion (CTO) are limited. We aimed to investigate the long-term outcomes of substitution of drug-eluting stents (DES) by DCB.

Methods

We compared the outcomes of less DES strategy (DCB alone or combined with DES) and DES-only strategy in treating de novo coronary CTO in this prospective, observational, multicenter study. The primary endpoints were major adverse cardiovascular events (MACE), target vessel revascularization, myocardial infarction, and death during 3-year follow-up. The secondary endpoints were late lumen loss (LLL) and restenosis until 1-year after operation.

Results

Of the 591 eligible patients consecutively enrolled between January 2015 and December 2019, 281 (290 lesions) were treated with DCB (DCB-only or combined with DES) and 310 (319 lesions) with DES only. In the DCB group, 147 (50.7%) lesions were treated using DCB-only, and the bailout stenting rate was relatively low (3.1%). The average stent length per lesion in the DCB group was significantly shorter compared with the DES-only group (21.5 ± 25.5 mm vs. 54.5 ± 26.0 mm, p < 0.001). A total of 112 patients in the DCB group and 71 patients in the DES-only group (38.6% vs. 22.3%, p < 0.001) completed angiographic follow-up until 1-year, and LLL was much less in the DCB group (-0.08 ± 0.65 mm vs. 0.35 ± 0.62 mm, p < 0.001). There were no significant differences in restenosis occurrence between the two groups (20.5% vs. 19.7%, p > 0.999). The Kaplan-Meier estimates of MACE at 3-year (11.8% vs. 12.0%, log-rank p = 0.688) was similar between the groups.

Conclusion

Percutaneous coronary intervention with DCB is a potential "stent-less" therapy for de novo CTO lesions with satisfactory long-term clinical results compared to the DES-only approach.

The Clinical Effects of Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Patients with Chronic Total Occlusion: A Meta-Analysis

Background

The clinical effects of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients with chronic total occlusion (CTO) lesions remain unclear.

Methods

We identified all full-text published studies that compared the effects of IVUS-guided CTO-PCI with angiography-guided CTO-PCI by searching electric databases including PubMed, Embase, Cochrane Library, and ISI Web of Science from the establishment to Nov 2021. There was no language limitation. The endpoints included the incidence of major adverse cardiac events (MACE), cardiac death, all-cause death, myocardial infarction (MI), and target vessel revascularization (TVR).

Results

Five studies involving a total of 2320 patients were included in this meta-analysis. Compared to the angiography-guided group, IVUS-guided PCI showed no significant reduction in the incidence of MACE (I² = 27.4%, P = 0.239; RR 0.929, 95% CI 0.765 to 1.128, P = 0.457), cardiac death (I² = 0.0%, P = 0.459; RR 0.574, 95% CI 0.299 to 1.103, P = 0.096), all-cause death (I² = 0.0%, P = 0.964; RR 0.677, 95% CI 0.395 to 1.163, P = 0.158), MI (I² = 46.7%, P = 0.131; RR0.836, 95% CI 0.508 to 1.377, P = 0.482), and TVR (I² = 21.2%, P = 0.279; RR 0.929, 95% CI 0.679 to 1.272, P = 0.648).

Conclusions

IVUS-guided PCI demonstrated no significant benefit on MACE, cardiac death, all-cause death, MI, and TVR in patients with CTO lesions. However, given the study's limitations, additional high-quality RCTs are needed.

Comparison of Clinical Outcomes Between Second-and First-Generation Drug-Eluting Stents in Patients With Chronic Total Occlusion Lesion: A Meta-Analysis

Background and Objectives: The second-generation drug-eluting stents have been used to treat chronic total occlusion lesion. However, there is limited evidence of the clinical outcomes that whether the second-generation drug-eluting stents is superior to first-generation ones in patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. The study aimed to compare the differences in clinical outcomes between the two generations drug-eluting stents in patients with those by a meta-analysis.

Methods: PubMed, Embase, the Cochrane library and Web of science databases were systemically searched before March, 2021. Randomized controlled trials and observational studies were included to compare the second-generation drug-eluting stents with the first-generation ones in patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. The clinical outcomes were major adverse cardiac events (MACE), target vessel revascularization, myocardial infarction, all-cause death. Fixed effects models were used to calculate the odds ratio (OR) and 95% confidence interval (CI) of each clinical outcome. Sensitivity analysis was performed to detect potential sources of heterogeneity. Subgroup analyses were used to assess the differential effects.

Results: The meta-analysis included eight studies involving 4,583 patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. Pooled analysis showed that the incidence of MACE (OR = 0.68, 95%CI 0.54–0.85, P = 0.0008), target vessel revascularization (OR = 0.70, 95%CI 0.54–0.91, P = 0.007), and myocardial infarction (OR = 0.58, 95%CI 0.37–0.93, P = 0.02) were lower in the second-generation drug-eluting stents compared with the first-generation ones. However, there was not difference in all-cause deaths between two drug-eluting stents (OR = 0.67, 95%CI 0.45–1.01, P = 0.05).

Conclusions: The second-generation drug-eluting stents are associated with lower MACE, target vessel revascularization, and myocardial infarction compared with the first-generation ones in patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. The results of this study can provide a reference for the selection of stents in patients with chronic total occlusion lesion. Further randomized controlled trials are needed to verify that the second-generation drug-eluting stents is superior to the first-generation ones in patients with chronic total occlusion (Registered by PROSPERO, CRD42020158406).

The 2010s in clinical drug-eluting stent and bioresorbable scaffold research: a Dutch perspective

Dutch researchers were among the first to perform clinical studies in bare metal coronary stents, the use of which was initially limited by a high incidence of in-stent restenosis. This problem was greatly solved by the introduction of drug-eluting stents (DES). Nevertheless, enthusiasm about first-generation DES was subdued by discussions about a higher risk of very-late stent thrombosis and mortality, which stimulated the development, refinement, and rapid adoption of new DES with more biocompatible durable polymer coatings, biodegradable polymer coatings, or no coating at all. In terms of clinical DES research, the 2010s were characterised by numerous large-scale randomised trials in all-comers and patients with minimal exclusion criteria. Bioresorbable scaffolds (BRS) were developed and investigated. The Igaki-Tamai scaffold without drug elution was clinically tested in the Netherlands in 1999, followed by an everolimus-eluting BRS (Absorb) which showed favourable imaging and clinical results. Afterwards, multiple clinical trials comparing Absorb and its metallic counterpart were performed, revealing an increased rate of scaffold thrombosis during follow-up. Based on these studies, the commercialisation of the device was subsequently halted. Novel technologies are being developed to overcome shortcomings of first-generation BRS. In this narrative review, we look back on numerous devices and on the DES and BRS trials reported by Dutch researchers.

Late-term safety and effectiveness of everolimus-eluting stents in chronic total coronary occlusion revascularization: Final 4-year results from the evaluation of the XIENCE coronary stent, Performance, and Technique in Chronic Total Occlusions (EXPERT CTO) multicenter trial

BACKGROUND

Limited study has detailed the late-term safety and efficacy of chronic total coronary occlusion (CTO) revascularization among multiple centers applying modern techniques and with newer-generation drug-eluting stents.

METHODS

Among 20 centers, 222 patients enrolled in the XIENCE coronary stent, performance, and technique (EXPERT) CTO trial underwent CTO percutaneous coronary intervention (PCI) with everolimus-eluting stents (EES). Through planned 4-year follow-up, the primary composite endpoint of major adverse cardiac events (MACE; death, myocardial infarction [MI] and target lesion revascularization) and rates of individual component endpoints and stent thrombosis were determined.

RESULTS

Demographic, lesion, and procedural characteristics included prior bypass surgery, 9.9%; diabetes, 40.1%; lesion length, 36.1 ± 18.5 mm; and stent length, 51.7 ± 27.2 mm. By 4 years, MACE rates were 31.6 and 22.4% by the pre-specified ARC and per-protocol definitions, respectively. Clinically-indicated target lesion revascularization at 4 years was 11.3%. In landmark analyses of events beyond the first year of revascularization, the annualized rates of target vessel-related MI and clinically-indicated target lesion revascularization were 0.53 and 1.3%, respectively. Through 4 years, the cumulative definite/probable stent thrombosis rate was 1.7% with no events occurring beyond the initial year of index revascularization.

CONCLUSIONS

In a multicenter registration trial representing contemporary technique and EES, these results demonstrate sustained long-term safety and effectiveness of EES in CTO percutaneous revascularization and can be used to inform shared decision making with patients being considered for CTO PCI relative to late safety and vessel patency.

Long-term safety of bioresorbable scaffolds: insights from a network meta-analysis including 91 trials

AIMS

The aim of this study was to investigate the long-term safety and efficacy of biodegradable scaffolds and metallic stents.

METHODS AND RESULTS

We analysed a total of 91 randomised controlled trials with a mean follow-up of 3.7 years in 105,842 patients which compared two or more coronary metallic stents or biodegradable scaffolds and reported the long-term clinical outcomes (≥2 years). Network meta-analysis showed that patients treated with the Absorb bioresorbable vascular scaffold (BVS) had a significantly higher risk of definite or probable scaffold thrombosis (ScT) compared to those treated with metallic DES. The risk of very late ScT was highest with the Absorb BVS among comparators. Pairwise conventional meta-analysis demonstrated that the elevated risk of ScT with Absorb BVS compared to cobalt-chromium everolimus-eluting stents was consistent across the time points of ≤30 days (early), 31 days - 1 year (late) and >1 year (very late) ScT. In addition, target lesion failure rates were significantly higher in the Absorb BVS cohort, driven by both increased risk of target vessel myocardial infarction and ischaemia-driven target lesion revascularisation.

CONCLUSIONS

Absorb BVS implantation was associated with increased risk of long-term and very late ScT compared to current-generation metallic DES. The risk of ScT occurred with a rising trend beyond one year.

Imaging during percutaneous coronary intervention for optimizing outcomes

Angiography is the current gold standard for imaging during percutaneous coronary interventions but has significant limitations. Catheter-based intravascular imaging techniques such as intravascular ultrasound and the more recent optical coherence tomography have the potential to overcome these limitations and thus optimize clinical outcomes. In this update, we discussed the current applications of the available imaging techniques, existing evidence, continuing unmet needs, and potential areas for further research.

Randomized Multicenter Trial Investigating Angiographic Outcomes of Hybrid Sirolimus-Eluting Stents With Biodegradable Polymer Compared With Everolimus-Eluting Stents With Durable Polymer in Chronic Total Occlusions: The PRISON IV Trial

OBJECTIVES

The aim of this study was to investigate the efficacy and safety of the hybrid ultrathin-strut sirolimus-eluting stent (SES) with biodegradable polymer compared with the thin-strut everolimus-eluting stent (EES) with durable polymer in successfully recanalized chronic total occlusions (CTOs).

BACKGROUND

The introduction of drug-eluting stents revolutionized the treatment of CTOs. However, limited data are available on new-generation drug-eluting stents with biodegradable polymer in CTOs.

METHODS

In this multicenter trial, patients were randomized, after successful CTO recanalization, to either SES or EES. The primary noninferiority endpoint was in-segment late lumen loss (noninferiority margin 0.2 mm). Secondary endpoints included in-stent late lumen loss and clinical endpoints.

RESULTS

Overall, 330 patients were included. At 9 months, angiography was available in 281 patients (85%). Duration of occlusion ≥3 months was 92.5%, with mean stent length of 52.4 ± 28.1 mm versus 52.3 ± 26.5 mm in the SES and EES groups. The primary noninferiority endpoint, in-segment late lumen loss, was not met for SES versus EES (0.13 ± 0.63 mm vs. 0.02 ± 0.47 mm; p = 0.08, 2-sided; difference 0.11 mm; 95% confidence interval: -0.01 to 0.25 mm; p_{noninferiority} = 0.11, 1-sided). In-stent late lumen loss was comparable between SES and EES (0.12 ± 0.59 mm vs. 0.07 ± 0.46 mm; p = 0.52). The incidence of in-stent and in-segment binary restenosis was significantly higher with SES compared with EES (8.0% vs. 2.1%; p = 0.028), with comparable rates of reocclusions (2.2% vs. 1.4%; p = 0.68). Clinically indicated target lesion and target vessel revascularization (9.2% vs. 4.0% [p = 0.08] and 9.2% vs. 6.0% [p = 0.33]), target vessel failure (9.9% vs. 6.6%; p = 0.35), and definite or probable stent thrombosis (0.7% vs. 0.7%; p = 1.00) were comparable between the SES and EES groups.

CONCLUSIONS

This randomized trial failed to show noninferiority of hybrid SES relative to EES in terms of in-segment late lumen loss in successfully recanalized CTOs. Furthermore, a statistically significantly higher rate of binary restenosis was found with SES.

Percutaneous Coronary Intervention Versus Optimal Medical Therapy for Chronic Total Coronary Occlusion With Well-Developed Collaterals

BACKGROUND

The impact of percutaneous coronary intervention (PCI) on chronic total occlusion in patients with well-developed collaterals is not clear.

METHODS AND RESULTS

A total of 640 chronic total occlusion patients with collateral flow grade ≥2 were divided into 2 groups; chronic total occlusion patients either treated with PCI (the PCI group; n=305) or optimal medical therapy (the optimal medical therapy group; n=335). To adjust for potential confounders, a propensity score matching analysis was performed. Major clinical outcomes were compared between the 2 groups up to 5 years. In the entire population, the PCI group had a lower hazard of myocardial infarction (hazard ratio [HR], 0.177; P=0.039; 95% confidence interval [CI], 0.03-0.91) and the composite of total death or myocardial infarction (HR, 0.298; P=0.017; 95% CI, 0.11-0.80); however, it showed higher hazard of target lesion revascularization (HR, 3.942; P=0.003; 95% CI, 1.58-9.81) and target vessel revascularization (HR, 4.218; P=0.001; 95% CI, 1.85-9.60). After propensity score matching, a total of 158 matched pairs were generated. Although the PCI group showed a higher hazard of target lesion revascularization (HR, 2.868; P=0.027; 95% CI, 1.13-7.31) and target vessel revascularization (HR=2.62; P=0.022; 95% CI, 1.15-5.97), it still exhibited a lower incidence of the composite of total death or myocardial infarction (HR, 0.263; P=0.017; 95% CI, 0.087-0.790). The mean ejection fraction was improved from 47.8% to 51.6% (P<0.001) after PCI.

CONCLUSIONS

In our study, successful revascularization by PCI for chronic total occlusion lesions with well-developed collaterals was associated with lower incidence of death and myocardial infarction, improved left ventricular function, but increased repeat revascularization rate.

Management standards for stable coronary artery disease in India

Coronary artery disease (CAD) is one of the important causes of cardiovascular morbidity and mortality globally, giving rise to more than 7 million deaths annually. An increasing burden of CAD in India is a major cause of concern with angina being the leading manifestation. Stable coronary artery disease (SCAD) is characterised by episodes of transient central chest pain (angina pectoris), often triggered by exercise, emotion or other forms of stress, generally triggered by a reversible mismatch between myocardial oxygen demand and supply resulting in myocardial ischemia or hypoxia. A stabilised, frequently asymptomatic phase following an acute coronary syndrome (ACS) is also classified as SCAD. This definition of SCAD also encompasses vasospastic and microvascular angina under the common umbrella.

Primary Stenting of Totally Occluded Native Coronary Arteries III (PRISON III): a randomised comparison of sirolimus-eluting stent implantation with zotarolimus-eluting stent implantation for the treatment of total coronary occlusions

AIMS

We investigated whether sirolimus-eluting stents (SES) are superior to next-generation zotarolimus-eluting stents (ZES) in treating patients with total coronary occlusions (TCO).

METHODS AND RESULTS

In a prospective, randomised trial we compared the SES with the zotarolimus-eluting stent (ZES; Endeavor or Resolute) after successful recanalisation of TCO. During the first phase of the trial, 51 patients were assigned to receive the SES and 46 patients to receive the Endeavor ZES. In the second phase we randomised 103 patients to the SES group and 104 patients to the Resolute ZES group. The primary endpoint was in-segment late lumen loss at eight-month follow-up. At eight months, patients in the SES group had less in-segment and in-stent late loss as compared to the Endeavor group: -0.13±0.3 mm vs. 0.27±0.6 mm (p=0.0002) and -0.13±0.5 mm vs. 0.54±0.5 mm (p<0.0001), respectively. In contrast, the SES and the Resolute ZES showed comparable amounts of in-segment (-0.03±0.7 mm vs. -0.10±0.7 mm, p=0.6) and in-stent (0.03±0.8 mm vs. 0.05±0.8 mm, p=0.9) late loss.

CONCLUSIONS

In the treatment of TCOs, the SES was associated with superior angiographic outcomes compared to the Endeavor ZES. On the other hand, the SES and the Resolute ZES showed comparable angiographic outcomes.

Clinical Impact of Intravascular Ultrasound-Guided Chronic Total Occlusion Intervention With Zotarolimus-Eluting Versus Biolimus-Eluting Stent Implantation: Randomized Study

BACKGROUND

There have been no randomized studies comparing intravascular ultrasound (IVUS)-guided versus conventional angiography-guided chronic total occlusion (CTO) intervention using new-generation drug-eluting stent Therefore, we conducted a prospective, randomized, multicenter trial designed to test the hypothesis that IVUS-guided CTO intervention is superior to angiography-guided intervention.

METHODS AND RESULTS

After successful guidewire crossing, 402 patients with CTOs were randomized to the IVUS-guided group (n=201) or the angiography-guided group (n=201) and secondarily randomized to Resolute zotarolimus-eluting stents or Nobori biolimus-eluting stents. The primary and secondary end points were cardiac death and a major adverse cardiac event defined as the composite of cardiac death, myocardial infarction, or target-vessel revascularization, respectively. After 12-month follow-up, the rate of cardiac death was not significantly different between the IVUS-guided group (0%) and the angiography-guided group (1.0%; P by log-rank test=0.16). However, major adverse cardiac event rates were significantly lower in the IVUS-guided group than that in the angiography-guided group (2.6% versus 7.1%; P=0.035; hazard ratio, 0.35; 95% confidence interval, 0.13-0.97). Occurrence of the composite of cardiac death or myocardial infarction was significantly lower in the IVUS-guided group (0%) than in the angiography-guided group (2.0%; P=0.045). The rates of target-vessel revascularization were not significantly different between the 2 groups. In the comparison between Resolute zotarolimus-eluting stent and Nobori biolimus-eluting stent, major adverse cardiac event rates were not significantly different (4.0% versus 5.7%; P=0.45).

CONCLUSIONS

Although IVUS-guided CTO intervention did not significantly reduce cardiac mortality, this randomized study demonstrated that IVUS-guided CTO intervention might improve 12-month major adverse cardiac event rate after new-generation drug-eluting stent implantation when compared with conventional angiography-guided CTO intervention.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01563952.

WITHDRAWN: Drug-eluting stents versus bare metal stents for angina or acute coronary syndromes

This review 'topic' has been included in work being carried out as part of a Health Technology Assessment commissioned by the National Institute for Clinical Excellence in England and Wales. Details of this research is available via www.nice.org.uk.

The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the HTA programme, NICE, NIHR, NHS or the Department of Health.

The review has been split into 2 reviews that will be published as "Drug‐eluting stents versus bare‐metal stents for stable ischaemic heart disease" and "Drug‐eluting stents versus bare‐metal stents for acute coronary syndrome".

The editorial group responsible for this previously published document have withdrawn it from publication.

Usefulness of intravascular ultrasound guidance in percutaneous coronary intervention with second-generation drug-eluting stents for chronic total occlusions (from the Multicenter Korean-Chronic Total Occlusion Registry)

Despite the usefulness of intravascular ultrasound (IVUS) in percutaneous coronary intervention (PCI), the impact of IVUS guidance on clinical outcomes, particularly for chronic total occlusion (CTO) intervention, has rarely been studied. We sought to investigate the clinical usefulness of IVUS-guided CTO intervention with second-generation drug-eluting stent implantation. From 2007 to 2009, a total of 2,568 patients were enrolled in the Korean-CTO registry and 534 patients with successful implantation of second-generation drug-eluting stents were analyzed. IVUS-guided PCI was performed on 206 patients (39%). Clinical outcomes at 2 years were compared between the IVUS-guidance group and the angiography-guidance group in 201 propensity score-matched pairs. The primary end point was the occurrence of definite or probable stent thrombosis. Clinical characteristics were similar between both groups after matching. At 2 years, the IVUS-guidance group showed significantly less stent thrombosis than the angiography-guidance group (0% vs 3.0%, p = 0.014) and a lesser trend toward myocardial infarction (1.0% vs 4.0%, p = 0.058). Target lesion revascularization (TLR) and major adverse cardiovascular event rates were similar. However, a significant interaction was observed between the use of IVUS and lesion length for predicting the TLR (p = 0.037), suggesting usefulness of IVUS in long-lesion (≥3 cm) relative to short-lesion CTO. In conclusion, although IVUS-guided CTO PCI was not associated with a reduction in overall major adverse cardiovascular events, IVUS guidance appears to be associated with a reduction of stent thrombosis and myocardial infarction compared with angiography-guided CTO PCI. Additionally, TLR occurred less frequently in the IVUS-guidance group, especially for long lesions.

Percutaneous Treatment of Coronary Chronic Total Occlusions Part 1: Rationale and Outcomes

Coronary chronic total occlusions (CTOs) are commonly encountered in patients with coronary artery disease. Compared to patients without coronary CTOs, those with CTO have worse clinical outcomes and lower likelihood of complete coronary revascularisation. Successful CTO percutaneous coronary intervention (PCI) can significantly improve angina and improve left ventricular function. Although currently unproven, successful CTO PCI might also reduce the risk for arrhythmic events in patients with ischaemic cardiomyopathy, provide better tolerance of future acute coronary syndrome, and possibly improve survival. Evaluation by a heart team comprised of both interventional and non-interventional cardiologists and cardiac surgeons is important for determining the optimal revascularisation strategy in patients with coronary artery disease and CTOs. Ad hoc CTO PCI is generally not recommended, so as to allow sufficient time for (a) discussion with the patient about the indications, goals, risks, and alternatives to PCI; (b) careful procedural planning; and (c) contrast and radiation exposure minimisation. Use of drug-eluting stents is recommended for CTO PCI, given the lower rates of angiographic restenosis compared to bare metal stents.

Late catch-up in lumen diameter at five-year angiography in MACE-free patients treated with sirolimus-eluting stents in the Primary Stenting of Totally Occluded Native Coronary Arteries: a randomised comparison of bare metal stent implantation with sirolimus-eluting stent implantation for the treatment of total coronary occlusions (PRISON II)

AIMS

The present study was designed to examine the five-year angiographic follow-up of MACE-free patients enrolled in the PRISON II study.

METHODS AND RESULTS

In the PRISON II study a total of 200 patients were randomised to either bare metal stents (BMS) or sirolimus-eluting stents (SES) after successful recanalisation of total coronary occlusions (TCO). Patients free of MACE with available angiography at six months were approached for repeated angiography at five years. The primary endpoint was in-stent very late luminal loss (VLLL) at five years. The secondary endpoint was additional late luminal loss (ALLL) between six months and five years. At five years, repeated angiography was performed in 72 patients, 50/82 (61%) in the SES group and 22/58 (38%) in the BMS group. In-stent VLLL was lower in the SES group (0.19 mm ± 0.72 vs. 0.51 mm ± 0.71, p=0.09) compared to the BMS group and in-segment VLLL was comparable in both groups (0.01 mm±0.58 vs. 0.03 mm ± 0.73, p=0.89). Late catch-up in lumen diameter was observed in the SES group with a trend towards increased ALLL compared to the BMS group (in-stent, 0.35 mm ± 0.88 vs. 0.04 mm ± 0.81, p=0.16; in-segment, 0.20 mm ± 0.74 vs. -0.05 mm ± 0.73, p=0.19).

CONCLUSIONS

At five-year angiographic follow-up, late catch-up was observed after successful recanalisation of TCOs treated with SES. Despite a late catch-up, the angiographic results of SES were superior in-stent and similar in-segment compared to BMS.

Coronary stent thrombosis: current insights into new drug-eluting stent designs

The advances of interventional cardiology have been achieved by new device development, finding appropriate drug regimes, and understanding of pathomechanism. Drug-eluting stents (DES) implantation with dual anti-platelet therapy reduced revascularization without increasing mortality or myocardial infarction compared with bare-metal stenting. However, late-term stent thrombosis (ST) and restenosis limited its value and raised the safety concern. Main mechanisms of this phenomenon are impaired endothelialization and hypersensitivity reaction with polymer. The second generation DES further improved safety and/or efficacy by using thinner stent strut and biocompatible polymer. Recently, new concept DES with biodegradable polymer, polymer-free and bioabsorbable scaffold are under investigation in the quest to minimize the risk of ST.

Five-year outcomes in patients with chronic total coronary occlusion treated with drug-eluting vs bare-metal stents: a case-control study

BACKGROUND

Limited data exist on long-term safety and effectiveness of drug-eluting stents (DESs) in true chronic total coronary occlusion (CTO) settings. We evaluated 5-year clinical outcomes of patients with CTO treated successfully with DES vs bare-metal stent (BMS).

METHODS

We compared the 5-year clinical outcomes of 156 patients treated with DES implantation with outcomes of a historical cohort of 159 patients treated with BMS. Primary end point was freedom from major adverse cardiac events (MACEs; defined as death, myocardial infarction [MI], and target lesion revascularization [TLR]); secondary end points were freedom from target vessel failure (TVF; combination of target vessel revascularization, MI, and cardiac death) and TLR at 5 years.

RESULTS

After 5 years, the DES group had significantly superior event-free survival from MACE (84% vs 69%; log rank P < 0.001), TVF (71% vs 84%; P = 0.002), and TLR (77% vs 92%; P = 0.0001), compared with the BMS group. The Cox proportional hazards model identified BMS vs DES (adjusted hazard ratio [HR] = 3.37; 95% confidence interval [CI], 1.85-6.17; P = 0.001), final minimal lumen diameter (HR, 0.27; 95% CI, 0.14-0.52; P = 0.0001), and stent length (HR, 1.01; 95% CI, 1.00-1.03; P = 0.03) as independent predictors of MACE at 5-year follow-up. Twelve (7%) and 7 (4%) stent thromboses occurred in the DES and BMS groups (P = 0.23), respectively.

CONCLUSIONS

After 5 years, DESs were superior to BMSs in reducing MACE, TVF, and TLR in patients with CTO and should be the preferred strategy.

A randomized multicenter comparison of hybrid sirolimus-eluting stents with bioresorbable polymer versus everolimus-eluting stents with durable polymer in total coronary occlusion: rationale and design of the Primary Stenting of Occluded Native Coronary Arteries IV study

BACKGROUND

Percutaneous recanalization of total coronary occlusion (TCO) was historically hampered by high rates of restenosis and reocclusions. The PRISON II trial demonstrated a significant restenosis reduction in patients treated with sirolimus-eluting stents compared with bare metal stents for TCO. Similar reductions in restenosis were observed with the second-generation zotarolimus-eluting stent and everolimus-eluting stent. Despite favorable anti-restenotic efficacy, safety concerns evolved after identifying an increased rate of very late stent thrombosis (VLST) with drug-eluting stents (DES) for the treatment of TCO. Late malapposition caused by hypersensitivity reactions and chronic inflammation was suggested as a probable cause of these VLST. New DES with bioresorbable polymer coatings were developed to address these safety concerns. No randomized trials have evaluated the efficacy and safety of the new-generation DES with bioresorbable polymers in patients treated for TCO.

METHODS/DESIGN

The prospective, randomized, single-blinded, multicenter, non-inferiority PRISON IV trial was designed to evaluate the safety, efficacy, and angiographic outcome of hybrid sirolimus-eluting stents with bioresorbable polymers (Orsiro; Biotronik, Berlin, Germany) compared with everolimus-eluting stents with durable polymers (Xience Prime/Xpedition; Abbott Vascular, Santa Clara, CA, USA) in patients with successfully recanalized TCOs. In total, 330 patients have been randomly allocated to each treatment arm. Patients are eligible with estimated duration of TCO ≥4 weeks with evidence of ischemia in the supply area of the TCO. The primary endpoint is in-segment late luminal loss at 9-month follow-up angiography. Secondary angiographic endpoints include in-stent late luminal loss, minimal luminal diameter, percentage of diameter stenosis, in-stent and in-segment binary restenosis and reocclusions at 9-month follow-up. Additionally, optical coherence tomography is performed in the first 60 randomized patients at 9 months to assess neointima thickness, percentage of neointima coverage, and stent strut malapposition and coverage. Personnel blinded to the allocated treatment will review all angiographic and optical coherence assessments. Secondary clinical endpoints include major adverse cardiac events, clinically driven target vessel revascularization, target vessel failure and stent thrombosis to 5-year clinical follow-up. An independent clinical event committee blinded to the allocated treatment will review all clinical events.

TRIAL REGISTRATION

Clinical Trials.gov: NCT01516723. Patient recruitment started in February 2012.