Delayed arterial healing and increased late stent thrombosis at culprit sites after drug-eluting stent placement for acute myocardial infarction patients: an autopsy study

Long-Term Efficacy and Safety of Everolimus-Eluting Stent Implantation in Japanese Patients with Acute Coronary Syndrome: Five-Year Real-World Data from the Tokyo-MD PCI Study

Background

The long-term safety of first-generation drug-eluting stent (DES) in acute coronary syndrome (ACS) was controversial.

Purpose

The purpose of this study was to establish 5-year real-world data regarding the long-term efficacy and safety of second-generation DES in Japanese patients with ACS.

Methods

The Tokyo-MD PCI study is a multicenter, observational cohort study enrolling consecutive patients who underwent everolimus-eluting stent (EES) implantation. The 5-year clinical events were compared between the ACS group (n = 644) and the stable coronary artery disease (SCAD) group (n = 1255). The primary efficacy endpoint was ischemia-driven target lesion revascularization (TLR), and the primary safety endpoint was the composite of all-cause death or myocardial infarction (MI).

Results

The median follow-up duration was 5.4 years. The cumulative incidence of ischemia-driven TLR was similar between ACS and SCAD (1 year: 3.0% versus 2.7%; P=0.682, 1-5 years: 2.7% versus 2.9%; P=0.864). The cumulative incidence of all-cause death or MI within 1 year was significantly higher in ACS than in SCAD (7.4% versus 3.8%; P < 0.001); however, ACS did not increase the risk of all-cause death or MI after adjusting confounders (adjusted hazard ratio, 1.260; 95% confidence interval, 0.774-2.053; P=0.352). From 1 to 5 years, the cumulative incidence of all-cause death or MI was not significantly different between ACS and SCAD (11.6% versus 11.4%; P=0.706). The cumulative incidence of very late stent thrombosis was low and similar between ACS and SCAD (0.2% versus 0.2%; P=0.942).

Conclusion

This real-world registry suggested that EES has comparable long-term efficacy and safety in patients with ACS and SCAD.

Trends in Death Rate 2009 to 2018 Following Percutaneous Coronary Intervention Stratified by Acuteness of Presentation

Percutaneous coronary intervention (PCI) has evolved dramatically, along with patient complexity. We studied trends in in-hospital mortality with changes in patient complexity over the last decade stratified by clinical presentation. The study population included all patients presenting to the cardiac catheterization lab between January 2009 and July 2018. Expected in-hospital mortality was calculated using the National Cardiovascular Data Registry CathPCI risk scoring system. Yearly mean in-hospital mortality rates (%) were plotted and smoothed by weighted least squares regression for each presentation: ST-elevation myocardial infarction (STEMI), non-ST-elevation acute coronary syndrome (NSTE-ACS), and stable ischemic coronary artery disease (SI CAD). The overall cohort included 13,732 patients who underwent PCI during the study period, of whom 2,142 were for STEMI, 2,836 for NSTE-ACS, and 8,754 for SI CAD. Indications for PCI have changed over time, with more PCIs being performed for NSTE-ACS and STEMI than for SI CAD. NSTE-ACS and STEMI patients had a steady decrease in in-hospital mortality over time compared with SI CAD patients. Overall observed mortality continues to decrease in NSTE-ACS patients, with reduction in the observed mortality rate within the STEMI population to below expected since 2013. Patient complexity has not changed significantly. These results may be attributed to improved patient selection coupled with optimal pharmacotherapy with more robust therapies during procedure and hospitalization.

Biodegradable polymer sirolimus-eluting stents versus durable polymer everolimus-eluting stents in patients with ST-segment elevation myocardial infarction (BIOSTEMI): a single-blind, prospective, randomised superiority trial

BACKGROUND

Newer-generation drug-eluting stents that combine ultrathin strut metallic platforms with biodegradable polymers might facilitate vascular healing and improve clinical outcomes in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (PCI) compared with contemporary thin strut second-generation drug-eluting stents. We did a randomised clinical trial to investigate the safety and efficacy of ultrathin strut biodegradable polymer sirolimus-eluting stents versus thin strut durable polymer everolimus-eluting stents in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI.

METHODS

The BIOSTEMI trial was an investigator-initiated, multicentre, prospective, single-blind, randomised superiority trial at ten hospitals in Switzerland. Patients aged 18 years or older with acute STEMI who were referred for primary PCI were eligible to participate. Patients were randomly allocated (1:1) to either biodegradable polymer sirolimus-eluting stents or durable polymer everolimus-eluting stents. Central randomisation was done based on a computer-generated allocation sequence with variable block sizes of 2, 4, and 6, which was stratified by centre, diabetes status, and presence or absence of multivessel coronary artery disease, and concealed using a secure web-based system. Patients and treating physicians were aware of group allocations, whereas outcome assessors were masked to the allocated stent. The experimental stent (Orsiro; Biotronik; Bülach, Switzerland) consisted of an ultrathin strut cobalt-chromium metallic stent platform releasing sirolimus from a biodegradable polymer. The control stent (Xience Xpedition/Alpine; Abbott Vascular, Abbott Park, IL, USA) consisted of a thin strut cobalt-chromium stent platform that releases everolimus from a durable polymer. The primary endpoint was target lesion failure, a composite of cardiac death, target vessel myocardial reinfarction (Q-wave and non-Q-wave), and clinically-indicated target lesion revascularisation, within 12 months of the index procedure. All analyses were done with the individual participant as the unit of analysis and according to the intention-to-treat principle. The trial was registered with ClinicalTrials.gov, number NCT02579031.

FINDINGS

Between April 26, 2016, and March 9, 2018, we randomly assigned 1300 patients (1623 lesions) with acute myocardial infarction to treatment with biodegradable polymer sirolimus-eluting stents (649 patients and 816 lesions) or durable polymer everolimus-eluting stents (651 patients and 806 lesions). At 12 months, follow-up data were available for 614 (95%) patients treated with biodegradable polymer sirolimus-eluting stents and 626 (96%) patients treated with durable polymer everolimus-eluting stents. The primary composite endpoint of target lesion failure occurred in 25 (4%) of 649 patients treated with biodegradable polymer sirolimus-eluting stents and 36 (6%) of 651 patients treated with durable polymer everolimus-eluting stents (difference -1·6 percentage points; rate ratio 0·59, 95% Bayesian credibility interval 0·37-0·94; posterior probability of superiority 0·986). Cardiac death, target vessel myocardial reinfarction, clinically-indicated target lesion revascularisation, and definite stent thrombosis were similar between the two treatment groups in the 12 months of follow-up.

INTERPRETATION

In patients with acute STEMI undergoing primary PCI, biodegradable polymer sirolimus-eluting stents were superior to durable polymer everolimus-eluting stents with respect to target lesion failure at 1 year. This difference was driven by reduced ischaemia-driven target lesion revascularisation in patients treated with biodegradable polymer sirolimus-eluting stents compared with durable polymer everolimus-eluting stents.

FUNDING

Biotronik.

Drug-coated balloon treatment in coronary artery disease: Recommendations from an Asia-Pacific Consensus Group

Coronary artery disease (CAD) is currently the leading cause of death globally, and the prevalence of this disease is growing more rapidly in the Asia-Pacific region than in Western countries. Although the use of metal coronary stents has rapidly increased thanks to the advancement of safety and efficacy of newer generation drug eluting stent (DES), patients are still negatively affected by some the inherent limitations of this type of treatment, such as stent thrombosis or restenosis, including neoatherosclerosis, and the obligatory use of dual antiplatelet therapy (DAPT) with unknown optimal duration. Drug-coated balloon (DCB) treatment is based on a leave-nothing-behind concept and therefore it is not limited by stent thrombosis and long-term DAPT; it directly delivers an anti-proliferative drug which is coated on a balloon after improving coronary blood flow. At present, DCB treatment is recommended as the first-line treatment option in metal stent-related restenosis linked to DES and bare metal stent. For de novo coronary lesions, the application of DCB treatment is extended further, for conditions such as small vessel disease, bifurcation lesions, and chronic total occlusion lesions, and others. Recently, several reports have suggested that fractional flow reserve guided DCB application was safe for larger coronary artery lesions and showed good long-term outcomes. Therefore, the aim of these recommendations of the consensus group was to provide adequate guidelines for patients with CAD based on objective evidence, and to extend the application of DCB to a wider variety of coronary diseases and guide their most effective and correct use in actual clinical practice.

Assessment of Vascular Patency and Inflammation with Intravascular Optical Coherence Tomography in Patients with Superficial Femoral Artery Disease Treated with Zilver PTX Stents

PURPOSE

Zilver PTX nitinol self-expanding drug-eluting stent with paclitaxel coating is effective for treatment of superficial femoral artery (SFA) disease. However, as with any stent, it induces a measure of vascular inflammatory response. The current clinical trial (NCT02734836) aimed to assess vascular patency, remodeling, and inflammatory markers with intravascular optical coherence tomography (OCT) in patients with SFA disease treated with Zilver PTX stents.

METHODS

Serial OCT examinations were performed in 13 patients at baseline and 12-month follow-up. Variables evaluated included neointimal area, luminal narrowing, thrombus area, stent expansion as well as measures of inflammation including, peri-strut low-intensity area (PLIA), macrophage arc, neovascularization, stent strut apposition and coverage.

RESULTS

Percentage of malapposed struts decreased from 10.3 ± 7.9% post-intervention to 1.1 ± 2.2% at 12-month follow-up, but one patient showed late-acquired stent malapposition (LASM). The percent of uncovered struts at follow-up was 3.0 ± 4.5%. Average expansion of stent cross-sectional area from baseline to follow-up was 35 ± 19%. The average neointimal area was 7.8 ± 3.8 mm². Maximal luminal narrowing was 61.1 ± 25.0%, and average luminal narrowing was 35.4 ± 18.2%. Average peri-strut low-intensity area (PLIA) per strut was 0.017 ± 0.018 mm². Average number of neovessels per mm of stent was 0.138 ± 0.181. Average macrophage angle per frame at follow-up was 7 ± 11°. Average thrombus area at follow-up was 0.0093 ± 0.0184 mm².

CONCLUSION

At 12-month follow-up, OCT analysis of Zilver PTX stent shows outward remodeling and minimal neointimal growth, but evidence of inflammation including PLIA, neovessels, thrombus and macrophages.

SUMMARY

Thirteen patients with PAD had paclitaxel-coated stents implanted in their SFAs and were then imaged with OCT at baseline and 12-month follow-up. OCT proxy metrics of inflammation were quantified.

Cut-off value of mal-apposition volume and depth for resolution at early phase of acute incomplete stent apposition after CoCr-EES implantation

The purpose of this study was to clarify a cut-off value for acute incomplete stent apposition (ISA) volume and maximum-depth to predict ISA resolution at 1- and 3-month follow-up in patients treated with cobalt-chromium everolimus-eluting stents. In total, 95 cases and 103 stents were registered in the MECHANISM-Elective sub-study. Acute ISA-volume was measured by the trapezoid rule. ISA resolution of cut-off value at 1- and 3-month was estimated by ISA-volume and maximum-depth using receiver operatorating characteristic curve analysis. The total number of analysed acute ISAs was 202 in the 1-month group and 225 in the 3-month group. A total of 123 ISAs at 1-month and a total of 169 ISAs at 3-month had been resolved. The cut-off value of ISA resolution by ISA-volume was 0.169 mm³ at 1-month (AUC: 0.725, sensitivity: 72.2%, specificity: 61.0%) and 0.295 mm³ at 3-month (AUC: 0.757, sensitivity: 75.0%, specificity: 60.4%). The cut-off value of ISA resolution by ISA maximum-depth demonstrated was 0.285 mm at 1-month (area under curve (AUC): 0.789, sensitivity: 70.9%, specificity: 69.9%) and 0.305 mm at 3-month (AUC: 0.663, sensitivity: 60.7%, specificity: 66.9%). Incidence of ISA resolution was significantly lower in combination with cut-off values of ISA-volume and maximum-depth (33%, p < 0.001, at 1-month; 56%, p = 0.003, at 3-month). Combining the cut-off value of ISA-volume with the maximum-depth might be helpful to consider the endpoint of the PCI procedure.

Implications of coronary artery bypass grafting and percutaneous coronary intervention on disease progression and the resulting changes to the physiology and pathology of the native coronary arteries

Myocardial revascularization can be achieved through 2 different methods: coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). Clinical trials comparing PCI and CABG generally use the composite end points of death, stroke, myocardial infarction and target vessel revascularization to determine superiority. Other effects of these interventions, including the preservation of normal coronary physiology, the response of the coronary tree to stressors and the response of the vessel wall to the revascularization intervention, are not routinely considered, but these may have significant implications for patients in the medium and long term. For PCI, relatively small differences in clinical outcomes have been reported between bare metal and drug-eluting stents, and the latter seems to have inconsistent and somewhat unpredictable effects on the vascular biology of the coronary arteries. In coronary bypass, the use of arterial conduits is associated with superior clinical outcomes, better long-term patency and the preservation of essentially normal coronary function after intervention. This review assembles the clinical, physiological, angiographic and pathological literature currently available and attempts to provide a more complete picture of the effects of CABG and PCI on coronary arteries.

Paclitaxel-Coated Balloon Angioplasty Versus Drug-Eluting Stent in Acute Myocardial Infarction: The REVELATION Randomized Trial

OBJECTIVES

This study sought to assess the efficacy and safety of a drug-coated balloon (DCB) strategy versus drug-eluting stent (DES) in primary percutaneous coronary intervention for ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

In primary percutaneous coronary intervention for STEMI, stenting has proved to be beneficial with regard to repeat revascularization, but not recurrent myocardial infarction or death, compared with balloon angioplasty alone. A strategy of DCB angioplasty without stenting might abolish the potential disadvantages of stent implantation while reducing the probability of restenosis observed in plain old balloon angioplasty.

METHODS

In the prospective, randomized, single-center REVELATION trial, we compared DCB with DES in patients presenting with STEMI. Patients with a new, nonseverely calcified culprit lesion in a native coronary artery and a residual stenosis of <50% after pre-dilatation were randomized to treatment with a DCB or DES. The primary endpoint was fractional flow reserve at 9 months, allowing for a functional measurement of the infarct-related lesion.

RESULTS

A total of 120 patients were included. At 9 months after enrolment, the mean fractional flow reserve value was 0.92 ± 0.05 in the DCB group (n = 35) and 0.91 ± 0.06 in the DES group (n = 38) (p = 0.27). One abrupt vessel closure requiring treatment occurred after treatment with DCB. Up to 9-months follow-up, 2 patients required nonurgent target lesion revascularization (1 in each group).

CONCLUSIONS

In the setting of STEMI, the DCB strategy was noninferior to DES in terms of fractional flow reserve assessed at 9 months. Furthermore, it seemed to be a safe and feasible strategy. (Revascularization With Paclitaxel-Coated Balloon Angioplasty Versus Drug-Eluting Stenting in Acute Myocardial Infarction [REVELATION]; NCT02219802).

Clinical outcomes and complications of treatment with supraflex stent in patients with coronary artery disease: One-year follow-up

Cardiovascular disease is one of the most important causes of morbidity and mortality in the world. Treatment in most patients is percutanseous coronary intervention. One of new generation drug-eluting stent (DES) is Sirolimus Eluting Stent. The current study was aimed to investigate the clinical outcomes and complications of treatment with supraflex stent during one year follow up in patients with coronary artery disease. This cross-sectional study was performed on patients with myocardial ischemia who were candidate for coronary angioplasty between 2017-2018 in Imam Reza Hospital, Mashhad, Iran.. Patients were followed for four primary end points including Target lesion revascularization (TLR), stent thrombosis (ST), myocardial infarction (MI) and cardiac death (CD) for one year. Descriptive data were analyzed by Freidman at a significance level of 0.05. A total of 287 patients were enrolled in the study. There was no TLR, MI, ST and CD records in the one month follow up. Six months follow up demonstrated three TLR patients and three MI patients, but no ST and death were reported. After one year follow up, three cases of CD and four ST cases were found in patients treated with supraflex stent. Based on the Freidman test, the highest rate of TLR was revealed in a six-month follow-up when comparing with one-month and twelve-month follow-up (p = 0.05). No significant relationship was found between the other cases. The most common complications associated with supraflex stent were TLR and MI in six-month follow-up. The most likely occurrence of CD and ST were found in one year follow up.

Real World Experience of a Biodegradable Polymer Sirolimus-Eluting Stent (Yukon Choice PC Elite) in Patients with Acute ST-Segment Elevation Myocardial Infarction Undergoing Primary Angioplasty: A Multicentric Observational Study (The Elite India Study)

BACKGROUND:

The durable polymer drug-eluting stents (DPDES) reduce the risk of repeated target vessel revascularisation (TLR) compared with BMS, but are associated with increased risk of late adverse events. In broadly inclusive populations, the biodegradable-polymer drug-eluting stents (BPDES) have favourable results compared with DPDES in the long term. However, its use in primary angioplasty has not been adequately studied, and data of real-world clinical experience is lacking.

AIM:

Aim of this study was to assess the safety and efficacy of Yukon Choice PC Elite sirolimus-eluting stent (a novel BPDES) in STEMI patients undergoing primary angioplasty.

METHODS:

We have presented here one-year clinical follow-up data of the Yukon Choice PC Elite sirolimus-eluting stent in patients undergoing primary angioplasty. A total of 636 patients were enrolled in this single arm, prospective observational study from five centres.

RESULTS:

This multicentric observational study showed excellent safety and efficacy profile of the novel device at one year follow up. The device-oriented composite endpoint (DOCE) of cardiac death, target-vessel reinfarction, and target-lesion revascularisation (TLR) was 2.7%, and the patient-oriented composite endpoint (POCE) of all-cause death, any myocardial infarction, and any revascularisation was 4.2% at one year. Definite or probable stent thrombosis rate was 0.6%, and no events were recorded beyond 6 months of follow up.

CONCLUSIONS:

In patients with STEMI undergoing primary angioplasty, the use of Yukon Choice PC Elite (biodegradable polymer sirolimus-eluting stent) has excellent results at one year. It, therefore, represents an attractive alternative to second generation DES in this high-risk population.

Re-endothelialisation after Synergy stent and Absorb bioresorbable vascular scaffold implantation in acute myocardial infarction: COVER-AMI study

BACKGROUND/AIMS

Drug eluting stent (DES) decrease the risk of restenosis by reducing the neointimal response. However, DES may impair strut coverage, and this has been associated with late stent/scaffold thrombosis. Bioresorbable vascular scaffold (BVS) may overcome the risk of stent/scaffold thrombosis when completely resorbed. The purpose of this randomised trial was to compare the arterial healing response in the short term, as a surrogate for safety and efficacy, between the metallic everolimus-eluting stent (Synergy; Boston Scientific, Marlborough, MA, USA) and the everolimus BVS (Absorb; Abbott Vascular, Santa Clara, CA, USA) in the particular setting of acute myocardial infarction (AMI). This pilot study sought to compare the neointimal response of metallic everolimus DES (Synergy) with polymeric everolimus BVS (Absorb) by optical coherence tomography (OCT) 3 months after an AMI.

METHODS

COVER-AMI was a single-centre, single-blind, non-inferiority, randomised controlled trial. Patients with ST segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention were randomly allocated (1:1) to treatment with the Synergy DES or Absorb BVS. The primary endpoint was the 3-month neointimal response assessed as the percentage of uncovered struts, neointimal thickness, in-stent/scaffold area obstruction, and pattern of neointima. The main secondary endpoint included the device-oriented composite endpoint according to the Academic Research Consortium definition.

RESULTS

Twenty patients without clinical and/or angiographic complications (Synergy (n = 10) or BVS (n = 10); mean age 59.0 years; 20% female) were enrolled in our centre. The stent diameter was higher in the Synergy group (3.7 ± 0.4 mm vs 3.4 ± 0.4 mm in the BVS group, p = 0.01). At 3 months, no significant differences in angiographic lumen loss were observed between the everolimus DES and everolimus BVS (0.04 mm (IQR 0.00-0.07) vs 0.11 mm (IQR 0.04-0.31), p = 0.165). OCT analysis of 420 cross-sections showed that the total neointimal area and in-stent obstruction were lower in the Synergy group, while OCT analysis at the strut level (n = 3942 struts) showed that the rate of uncovered struts was lower in the BVS group.

CONCLUSIONS

Stenting of culprit lesions in the setting of STEMI resulted in a nearly complete arterial healing for both the Synergy and the BVS devices. Lower neointimal thickness and in-stent obstruction but a higher rate of uncovered struts were observed in the Synergy group. These findings provide the basis for further exploration in clinically oriented outcome trials.

Assessment of strut coverage of everolimus-eluting platinum chromium stent 2 weeks after implantation by optical coherence tomography

The SYNERGY coronary stent is new-generation drug-eluting stents, which has a thin-strut platinum-chromium platform with everolimus in a biodegradable polymer applied to the abluminal surface. It would be speculated that favorable arterial healing with early strut coverage could be achieved. The present study investigated the degree of strut coverage using optical coherence tomography (OCT) 2 weeks after SYNERGY implantation and clinical factors contributing to strut coverage. A total of 29 patients who underwent staged percutaneous coronary intervention (PCI) to residual lesions 2 weeks after the index PCI with SYNERGY stent implantation were enrolled. At the time of staged PCI, OCT examinations of the SYNERGY stent were performed for conventional OCT analysis on both cross-sectional and strut level. SYNERGY stent showed a high level of strut coverage and apposition, and the percentage was 82.4 ± 12.4% and 96.2 ± 5.0%, respectively. The lesion complexity was significantly related to greater strut coverage on univariate analysis; however, it was found to be insignificant in multivariate analysis. Our findings suggest early arterial healing after SYNERGY stent implantation.

Outcomes of the amphilimus-eluting polymer-free stent for chronic total occlusion treatment: a multicentre experience

AIMS

Late stent thrombosis and delayed vessel wall healing remain an important issue in coronary vessels treated with drug-eluting stents (DES), especially when long-vessel segments need to be covered, like in chronic total occlusions (CTO). Avoiding polymer use to avoid chronic inflammatory responses is a potential solution to reduce target vessel failure (TVF). We aimed to validate the clinical safety and efficacy at 1 year of the polymer-free Cre8 DES vs. nonpolymer-free DES for the percutaneous treatment of CTO.

METHODS

Between September 2011 and August 2016, patients were prospectively enrolled in three CTO centres. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE), including cardiac death, any myocardial infarction, stent thrombosis, TVF and target vessel revascularization.

RESULTS

A total of 102 Cre8 and 133 non-Cre8 patients were enrolled. At 1 year, a low cumulative MACCE was observed in the Cre8 group (6.9%, respectively). Moreover, a numerical trend towards better MACCE was observed in the Cre8 group vs. the non-Cre8 group (6.9 vs. 14.3%; P = 0.065). The clinically driven TVF rate was not statistically different between Cre8 and non-Cre8 patients (6.9 vs. 9.8%; P = 0.373). A borderline significant difference regarding mortality was observed in favour of Cre8 patients (0 vs. 3.8%; P = 0.049).

CONCLUSION

Low rates of MACCE and TVF up to 1 year were observed in the Cre8 group, supportive of the use of polymer-free DES for lesions with high complexity.

Early vascular responses to everolimus-eluting cobalt-chromium stent in the culprit lesions of st-elevation myocardial infarction: results from a multicenter prospective optical coherence tomography study (MECHANISM-AMI 2-week follow-up study)

The use of cobalt-chromium everolimus-eluting stents (CoCr-EES) for ST-segment elevation myocardial infarction (STEMI) reduces the incidence of stent thrombosis compared with bare metal stents, and a substantial difference is apparent in the initial 2 weeks. However, vascular behavior during this early period remains unclear. This was a prospective study (MECHANISM-AMI-2W) to investigate early vascular responses in STEMI patients immediately after CoCr-EES implantation and at 2-week follow-up using frequency domain-optical coherence tomography (FD-OCT). The study enrolled 52 patients (age 63.7 ± 11.7 years, male 85.0%), of whom 44 patients were available for complete serial FD-OCT analyses. Both % uncovered struts and % malapposed struts were improved at 2-week follow-up (63 ± 20 vs. 21 ± 14%, p < 0.0001 and 7.3 ± 9.0 vs. 4.7 ± 5.9%, p = 0.005, respectively). Thrombus was decreased, with significant changes in longitudinal length to stent (28.8 ± 27.7 vs. 18.1 ± 20.2%, p = 0.0001) and maximal area (0.93 ± 0.84 vs. 0.65 ± 0.63 mm2, p = 0.034). As a result, the average lumen area was significantly larger at 2 weeks (6.49 ± 1.82 vs. 6.71 ± 1.89 mm2, p = 0.048, respectively). The number of dissection flaps was lower (0.86 ± 1.11 vs. 0.52 ± 0.90%, p = 0.024). In conclusion, this study showed early vascular responses to CoCr-EES for STEMI lesions-including a significant reduction of thrombus-that resulted in lumen enlargement, earlier progression of strut coverage, and improvements in strut apposition and dissection. The combination of these factors may therefore be responsible for the safety of CoCr-EES within the initial 2 weeks.

Targeted Delivery of Bioactive Molecules for Vascular Intervention and Tissue Engineering

Cardiovascular diseases are the leading cause of death in the United States. Treatment often requires surgical interventions to re-open occluded vessels, bypass severe occlusions, or stabilize aneurysms. Despite the short-term success of such interventions, many ultimately fail due to thrombosis or restenosis (following stent placement), or incomplete healing (such as after aneurysm coil placement). Bioactive molecules capable of modulating host tissue responses and preventing these complications have been identified, but systemic delivery is often harmful or ineffective. This review discusses the use of localized bioactive molecule delivery methods to enhance the long-term success of vascular interventions, such as drug-eluting stents and aneurysm coils, as well as nanoparticles for targeted molecule delivery. Vascular grafts in particular have poor patency in small diameter, high flow applications, such as coronary artery bypass grafting (CABG). Grafts fabricated from a variety of approaches may benefit from bioactive molecule incorporation to improve patency. Tissue engineering is an especially promising approach for vascular graft fabrication that may be conducive to incorporation of drugs or growth factors. Overall, localized and targeted delivery of bioactive molecules has shown promise for improving the outcomes of vascular interventions, with technologies such as drug-eluting stents showing excellent clinical success. However, many targeted vascular drug delivery systems have yet to reach the clinic. There is still a need to better optimize bioactive molecule release kinetics and identify synergistic biomolecule combinations before the clinical impact of these technologies can be realized.

Clinical Outcomes One Year and Beyond After Combination Sirolimus-Eluting Endothelial Progenitor Cell Capture Stenting During Primary Percutaneous Coronary Intervention in ST-Segment Elevation Myocardial Infarction

BACKGROUND/PURPOSE

Primary percutaneous coronary intervention (PCI) during acute ST-segment elevation myocardial infarction (STEMI) represents a thrombotic milieu and is associated with delayed healing after stenting. The pro-healing combination sirolimus eluting endothelial progenitor cell (EPC) capture stents encourage early endothelialization after stenting and may be beneficial in the STEMI population. We aim to evaluate the clinical outcomes one year and beyond for patients with STEMI who received the combination sirolimus eluting EPC capture stents during primary PCI.

METHODS/MATERIAL

All STEMI patients implanted with combination sirolimus eluting EPC capture stents during primary PCI from November 2013 to December 2016 were enrolled. The primary outcome was target lesion failure (TLF) at in-hospital, one-month, one-year and beyond one year.

RESULTS

A total of 260 consecutive STEMI patients (283 lesions) were implanted with 313 combination sirolimus eluting EPC capture stents during primary PCI. Mean age was 56.1 ± 11.2 years and 88.8% were male. One in ten patients (10.9%) had cardiogenic shock on presentation, 7.3% needed mechanical ventilation and 7.7% had intra-aortic balloon pump inserted. A total of 97.9% of lesions achieve final TIMI 3 flow. Device success was seen in all patients. At extended follow up period (median 23.4 months), the clinical outcomes were TLF 8.8%, major adverse cardiovascular events 10.8%, cardiac mortality 4.2%, target vessel myocardial infarction 3.4%, target lesion revascularization 3.8%, and definite stent thrombosis 1.9%.

CONCLUSIONS

This study demonstrated acceptable clinical outcomes for an all-comers STEMI patients undergoing primary PCI with the use of combination sirolimus eluting EPC cell capture stents.

Swine model of in-stent stenosis in the iliac artery evaluating the serial time course

The aim of this study was to propose a new animal model evaluating the serial time course of in-stent stenosis by repeated carotid artery catheterization in the same animal. 16 bare-metal stents were implanted in the normal external and internal iliac artery of 8 miniature pigs. Repeated measurements were performed in the same animal every 2 weeks for 12 weeks through carotid artery catheterization. The time course and peak neointimal proliferation were evaluated by intravascular ultrasound. Health of all animals was assessed by clinical and hematological examinations. As a result, 7 times of carotid artery catheterization was performed per pig, but all animals remained healthy without both any complications and hematological inflammatory abnormalities. The time course of neointimal proliferation of each stent was observed from the stage of hyperplasia to partial regression. The peak neointimal proliferation varied from 6 to 12 weeks despite implantation of identical stents using the same deployment method. In conclusion, repeated carotid artery catheterization to the same animal is feasible without animal health deterioration. This model should be useful to evaluate the time course of neointimal proliferation after stent deployment in preclinical study.

The effects of stenting on coronary endothelium from a molecular biological view: Time for improvement?

Coronary artery stenting following balloon angioplasty represents the gold standard in revascularization of coronary artery stenoses. However, stent deployment as well as percutaneous transluminal coronary angioplasty (PTCA) alone causes severe injury of vascular endothelium. The damaged endothelium is intrinsically repaired by locally derived endothelial cells and by circulating endothelial progenitor cells from the blood, leading to re‐population of the denuded regions within several weeks to months. However, the process of re‐endothelialization is often incomplete or dysfunctional, promoting in‐stent thrombosis and restenosis. The molecular and biomechanical mechanisms that influence the process of re‐endothelialization in stented segments are incompletely understood. Once the endothelium is restored, endothelial function might still be impaired. Several strategies have been followed to improve endothelial function after coronary stenting. In this review, the effects of stenting on coronary endothelium are outlined and current and future strategies to improve endothelial function after stent deployment are discussed.

Comparison of endothelial cell attachment on surfaces of biodegradable polymer-coated magnesium alloys in a microfluidic environment

Polymeric coatings can provide temporary stability to bioresorbable metallic stents at the initial stage of deployment by alleviating rapid degradation and providing better interaction with surrounding vasculature. To understand this interfacing biocompatibility, this study explored the endothelial-cytocompatibility of polymer-coated magnesium (Mg) alloys under static and dynamic conditions compared to that of non-coated Mg alloy surfaces. Poly (carbonate urethane) urea (PCUU) and poly (lactic-co-glycolic acid) (PLGA) were coated on Mg alloys (WE43, AZ31, ZWEKL, ZWEKC) and 316L stainless steel (316L SS, control sample), which were embedded into a microfluidic device to simulate a vascular environment with dynamic flow. The results from attachment and viability tests showed that more cells were attached on the polymer-coated Mg alloys than on non-coated Mg alloys in both static and dynamic conditions. In particular, the attachment and viability on PCUU-coated surfaces were significantly higher than that of PLGA-coated surfaces of WE43 and ZWEKC in both static and dynamic conditions, and of AZ31 in dynamic conditions (P<0.05). The elementary distribution map showed that there were relatively higher Carbon weight percentages and lower Mg weight percentages on PCUU-coated alloys than PLGA-coated alloys. Various levels of pittings were observed underneath the polymer coatings, and the pittings were more severe on the surface of Mg alloys that corroded rapidly. Polymer coatings are recommended to be applied on Mg alloys with relatively low corrosion rates, or after pre-stabilizing the substrate. PCUU-coating has more selective potential to enhance the biocompatibility and mitigate the endothelium damage of Mg alloy stenting.

Bioresorbable polymer-coated thin strut sirolimus-eluting stent vs durable polymer-coated everolimus-eluting stent in daily clinical practice: Propensity matched one-year results from interventional cardiology network registry

OBJECTIVES

We sought to determine the 1-year clinical follow-up in patients treated with the thin strut (71 μm) bioabsorbable polymer-coated sirolimus-eluting stent (BP-SES) vs durable coating everolimus eluting stent (DP-EES) in daily clinical routine.

BACKGROUND

Presence of durable polymers may be associated with late/very late stent thrombosis occurrence and the need for prolonged dual antiplatelet therapy. Bioabsorbable polymers may facilitate stent healing, thus enhancing clinical safety.

METHODS

Interventional Cardiology Network Registry is a prospective, multicenter, observational registry of 21,400 consecutive patients treated with PCI since 2010. We analyzed 4,670 patients treated with either a BP-SES (ALEX, Balton, Poland) or DP-EES (XIENCE, Abbott, USA) with available 1-year clinical follow-up using propensity-score matching. Outcomes included target vessel revascularization (TVR) as efficacy outcome and all cause death, myocardial infarction (MI), and definite/probable stent thrombosis as safety outcomes.

RESULTS

After propensity score matching, 1,649 patients treated with BP-SES and 1,649 patients treated with DP-EES were selected. Procedural and clinical characteristics were similar between both groups. There was no significant difference between tested groups in in-hospital mortality. One-year follow-up demonstrated comparable efficacy outcome, TVR (BP-SES 5.9% vs DP-EES 4.6% P = 0.45), as well as comparable safety outcomes, all cause death, MI and definite/probable stent thrombosis.

CONCLUSIONS

In this multicenter registry, the BP-SES thin strut biodegradable polymer-coated sirolimus-eluting stent demonstrated comparable clinical outcomes at 1-year after implantation to the DP-EES. These data support the relative safety and efficacy of DP-SES in a broad range of patients undergoing percutaneous coronary intervention.

40 Years of Percutaneous Coronary Intervention: History and Future Directions

The field of interventional cardiology has evolved significantly since the first percutaneous transluminal coronary angioplasty was performed 40 years ago. This evolution began with a balloon catheter mounted on a fixed wire and has progressed into bare-metal stents (BMS), first-generation drug-eluting stents (DES), second- and third-generation biodegradable polymer-based DES, and culminates with the advent of bioabsorbable stents, which are currently under development. Each step in technological advancement has improved outcomes, while new persisting challenges arise, caused by the stent scaffolds, the polymers employed, and the non-selective cytostatic and cytotoxic drugs eluted from the stents. Despite the promising technological advances made in stent technology, managing the balance between reductions in target lesion revascularization, stent thrombosis, and bleeding remain highly complex issues. This review summarizes the evolution of percutaneous coronary intervention with a focus on vascular dysfunction triggered by the non-selective drugs eluted from various stents. It also provides an overview of the mechanism of action of the drugs currently used in DES. We also discuss the efforts made in developing novel cell-selective drugs capable of inhibiting vascular smooth muscle cell (VSMC) proliferation, migration, and infiltration of inflammatory cells while allowing for complete reendothelialization. Lastly, in the era of precision medicine, considerations of patients’ genetic variance associated with myocardial infarction and in-stent restenosis are discussed. The combination of personalized medicine and improved stent platform with cell-selective drugs has the potential to solve the remaining challenges and improve the care of coronary artery disease patients.

A serial 3- and 9-year optical coherence tomography assessment of vascular healing response to sirolimus- and paclitaxel-eluting stents

Early-generation drug-eluting stents (DES) have been demonstrated to delay vascular healing. Limited optical coherence tomography (OCT) data on the very long-term neointimal response after DES implantation are available. The aim of this study was a serial OCT assessment of neointimal thickness, stent strut coverage, malapposition, and protrusion as markers of neointimal response at 3 and 9 years after implantation of sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES). In this single-centre, longitudinal study consecutive patients undergoing elective PCI with SES or PES were included. OCT analysis was performed after 3 and 9 years by the independent core laboratory. A total of 22 subjects (8 SES and 14 PES) underwent an OCT assessment at 3 and 9 years post index procedure. The lumen, neointimal and malapposition area and the neointimal thickness (SES ∆50 µm, p = 0.195, PES ∆10 µm, p = 0.951) did not change significantly over the 6 year follow-up. No differences in the incidence of uncovered, malapposed or protruding struts were found in each type of stent. At 3 and 9 years after PCI, implantation of early-generation SES and PES may be associated with similar neointimal thickness, strut coverage, malapposition and protrusion, as assessed by serial OCT examination among patients with uneventful follow-up at 3 years post procedure. The small size of the study warrants judicious interpretation of our results and confirmation in larger multimodality imaging studies, including patients treated with contemporary stent platforms.

The comparison of early healing 1-month after PCI among CoCr-everolimus-eluting stent (EES), biodegradable polymer (BP)-EES and BP-sirolimus-eluting stent: Insights from OFDI and coronary angioscopy

Background

Third-generation stents with abluminal biodegradable polymer (BP) might facilitate early healing. Therefore, we compared early healing between second-generation and third-generation stents using coronary angioscopy (CAS) and optical frequency domain imaging [OFDI].

Methods

We prospectively enrolled 30 consecutive patients with stent implantation for acute coronary syndrome (cobalt‑chromium [CoCr] everolimus-eluting stent [EES] [n = 10], BP-EES [n = 10], and BP-sirolimus eluting stent [SES] [n = 10]). All patients underwent CAS and OFDI 1 month after initial percutaneous coronary intervention. On OFDI, the stent coverage (SC), thrombus, and peri-strut low intensity area (PLIA) were assessed. CAS findings were recorded for the grade of SC, grade of yellow color (YC), and grade of the thrombus (TG).

Results

On OFDI, the incidences of any thrombus at the 1-month follow-up were 70%, 80%, and 80% in the CoCr-EES, BP-EES, and BP-SES groups, respectively. The percentage of coverage was comparable among the groups (CoCr-EES 79.8 vs. BP-EES 79.9 vs. BP-SES 80.1%, P = 0.96). However, the number of struts with PLIA was numerically higher in the BP-SES group than in the CoCr-EES and BP-EES groups (46.4 ± 25.1 vs. 21.6 ± 13.2 vs. 22.0 ± 7.2%, P = 0.08). In the CoCr-EES, BP-EES, and BP-SES groups, mean grades of SC were 1.25 ± 0.5, 1.25 ± 0.5, and 0.85 ± 0.70 (P = 0.60); mean grades of YC were 0.75 ± 0.5, 0.80 ± 0.45, and 0.88 ± 0.37 (P = 0.65), and mean grades of TG were 1.00 ± 1.00, 1.20 ± 0.83, and 0.88 ± 0.64 (P = 0.75), respectively.

Conclusion

Third-generation stents are not inferior to second-generation stents regarding stent coverage. However, PLIA on OFDI was often observed with BP-SESs, indicating involvement of the fibrin component.

Impact of out-stent plaque characteristics on vascular response after second generation drug-eluting stent implantation: iMAP-intravascular ultrasound and angioscopic study

Purpose

The purpose of this study is to elucidate the impact of out-stent plaque characteristics on vascular response after implantation of second generation drug-eluting stent (G2-DES).

Methods

Enrolled were 37 patients with 39 coronary artery lesions into which three types of G2-DES were successfully implanted (9 Nobori biolimus-, BES; 15 Xience everolimus-, EES; 15 Resolute zotarolimus-eluting stents; R-ZES). Immediately after (baseline) and one year after the implantation (follow-up), iMAP-intravascular ultrasound (IVUS) was performed to measure out-stent plaque volume (OSPV) and its components. Percent OSPV and vulnerable plaque index (VPI) were defined as percentile of OSPV to vessel volume and as percentile of lipidic plus necrotic volume to OSPV. Coronary angioscopy at follow-up rated the degree of arterial repair by neointimal stent coverage (NSC).

Results

Poor NSC was found in approximately 60% of each G2-DES. In BES, % OSPV at baseline was significantly greater in poor NSC than in good NSC (36.2 ± 3.9 vs. 27.3 ± 4.0%, P = 0.01). In EES, %OSPV was significantly greater in poor NSC than in good NSC (41.0 ± 4.1 vs. 32.6 ± 2.7%, P < 0.01). In R-ZES implantation, there was no significant difference with regards to %OSPV between poor and good NSC. In BES, VPI at baseline was significantly greater in poor NSC than good NSC (54.0 ± 5.8 vs. 42.2 ± 5.1%, P = 0.02). There was no significant difference with regards to VPI between poor and good NCS in EES and R-ZES.

Conclusions

Impact of out-stent plaque characteristics on vascular response was different among the three types of G2-DES.

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) in 2018

While primary percutaneous coronary intervention (PCI) has significantly contributed to improve the mortality in patients with ST segment elevation myocardial infarction even in cardiogenic shock, primary PCI is a standard of care in most of Japanese institutions. Whereas there are high numbers of available facilities providing primary PCI in Japan, there are no clear guidelines focusing on procedural aspect of the standardized care. Whilst updated guidelines for the management of acute myocardial infarction were recently published by European Society of Cardiology, the following major changes are indicated; (1) radial access and drug-eluting stent over bare metal stent were recommended as Class I indication, and (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. Although the primary PCI is consistently recommended in recent and previous guidelines, the device lag from Europe, the frequent usage of coronary imaging modalities in Japan, and the difference in available medical therapy or mechanical support may prevent direct application of European guidelines to Japanese population. The Task Force on Primary Percutaneous Coronary Intervention of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) has now proposed the expert consensus document for the management of acute myocardial infarction focusing on procedural aspect of primary PCI.

Rapamycin activates TGF receptor independently of its ligand: implications for endothelial dysfunction

Rapamycin, the macrolide immunosuppressant and active pharmaceutic in drug-eluting stents (DES), has a well-recognized antiproliferative action that involves inhibition of the mTOR pathway after binding to the cytosolic protein FKBP12. TGF receptor-type I (TGFRI) spontaneous activation is inhibited by the association with FKBP12. We hypothesized that rapamycin, in addition to inhibition of mTOR signaling, activates TGFRI independent of TGFβ. Human umbilical vein endothelial cells (HUVECs) were treated with rapamycin (10 nmol/l) and/or TGFβ RI kinase inhibitor (TGFRIi, 100 nmol/l) for 24 h. Rapamycin induced SMAD phosphorylation (SMAD1, SMAD2, and SMAD5) and PAI-1 up-regulation, which was specifically abrogated by SMAD2 knockdown. TGFRIi efficiently blocked phosphorylation of SMAD2, but not SMAD1/5. Interestingly, the inhibitor did not alter cell proliferation arrest induced by rapamycin. Active TGFβ secretion was not affected by the treatment. Neutralizing TGFβ experiments did not influence SMAD2 phosphorylation or PAI-1 expression indicating that activation of this pathway is independent of the ligand. In addition, rapamycin induction of endothelial-to-mesenchymal transition (EndMT) was potentiated by IL-1β and efficiently blocked by TGFRIi. In vivo, the prothrombogenic effects of rapamycin and up-regulation of PAI-1 in murine carotid arteries were reduced by TGFRIi treatment. In conclusion, we provide evidence that rapamycin activates TGF receptor independent of its ligand TGFβ, in concert with promotion of PAI-1 expression and changes in endothelial phenotype. These undesirable effects, the prothrombogenic state, and activation of EndMT are SMAD2-dependent and independent of the therapeutic rapamycin-induced cell proliferation arrest.

Vascular response to biolimus A-9 eluting stent in patients with shorter and prolonged dual antiplatelet therapy: optical coherence tomography sub-study of the NIPPON trial

Dual antiplatelet therapy (DAPT) with thienopyridine and aspirin is the standard care for the prevention of stent thrombosis. However, the optimal duration and effect of the duration of DAPT on intra-stent thrombus (IS-Th) formation are unknown. The NIPPON study (Nobori Dual Antiplatelet Therapy as Appropriate Duration) was an open label, randomized multicenter, assessor-blinded, trial designed to demonstrate the non-inferiority of shorter (6-month) DAPT to prolonged (18-month) DAPT, after biolimus A9 eluting stent implantation in 3773 patients at 130 sites in Japan. Among them, 101 patients were randomly allocated for an optical coherence tomography (OCT) sub-study to assess the difference of local IS-Th formation between the two groups. In addition to standard OCT parameters, the number of IS-Th formed was counted in each target stent at 8 months. Baseline patient characteristics were not different between the 6- and 18-month groups. IS-Th was detected in 9.8% of the cases and the presence of IS-Th was not significantly different between the two groups (10.9% in 6-month vs. 9.1% in 12-month, P = 0.76). Furthermore, the number of IS-Th formed was not significantly different between the two groups. This OCT sub-study was in line with the main NIPPON study which demonstrated the non-inferiority of 6-month DAPT to 18-month DAPT. Shorter DAPT duration did not promote progressive IS-Th formation at the mid-term time point.

Coronary plaque characteristics on baseline CT predict the need for late revascularization in symptomatic patients after percutaneous intervention

OBJECTIVES

To assess pre-procedural plaque characteristics as determined by coronary CT angiography (CCTA) and their associations with late revascularization in symptomatic post-procedural patients.

METHODS

Symptomatic patients with pre-procedural CCTA were prospectively enrolled and referred for invasive coronary angiography (ICA). Plaque characterization was performed on the basis of baseline CCTA data. Multivariate logistic regression analysis with a stepwise selection method was performed to identify independent predictors of late revascularization.

RESULTS

Seventy-eight patients with 134 lesions were included. Late revascularization was performed to treat 15 ISRs and 22 de novo lesions. Lesions with late revascularization showed higher prevalence rates of low-attenuation plaque (LAP) and positive remodelling (PR) (70.3% vs. 23.7% and 86.5% vs. 30.9%; both p < 0.001) at baseline CCTA. However, the incidence of spotty calcification or napkin-ring sign (NRS) was not significantly different between the subgroups. According to ROC curve analysis, PR and LAP showed the largest AUC values for diagnosing lesions with late revascularization (AUC = 0.78 and 0.73, both p < 0.001). In multivariate analysis, LAP and PR (odds ratio = 6.30 and 13.94; both p < 0.05) were revealed to be independent predictors for late revascularization.

CONCLUSIONS

LAP and PR observed by baseline CCTA independently predict late revascularization caused by ISR or progression of de novo lesions.

KEY POINTS

• LAP and PR observed by baseline CT are predictors of late revascularization. • NRS and spotty calcification are not associated with late revascularization. • CT plaque characterization is useful in identifying lesions at high risk of late revascularization.

PET Molecular Targets and Near-Infrared Fluorescence Imaging of Atherosclerosis

PURPOSE OF REVIEW

With this review, we aim to summarize the role of positron emission tomography (PET) and near-infrared fluorescence imaging (NIRF) in the detection of atherosclerosis.

RECENT FINDINGS

18F-FDG is an established measure of increased macrophage activity. However, due to its low specificity, new radiotracers have emerged for more specific detection of vascular inflammation and other high-risk plaque features such as microcalcification and neovascularization. Novel NIRF probes are engineered to sense endothelial damage as an early sign of plaque erosion as well as oxidized low-density lipoprotein (oxLDL) as a prime target for atherosclerosis. Integrated NIRF/OCT (optical coherence tomography) catheters enable to detect stent-associated microthrombi. Novel radiotracers can improve specificity of PET for imaging atherosclerosis. Advanced NIRF probes show promise for future application in human. Intravascular NIRF might play a prominent role in the detection of stent-induced vascular injury.

The evolution of coronary stents

INTRODUCTION

Percutaneous coronary intervention (PCI) is 40 years old this year. From its humble beginnings of experimental work, PCI has transitioned over years with coronary artery stenting now a standard medical procedure performed throughout the world. Areas covered: The conversion from plain old balloon angioplasty (POBA) to the present era of drug eluting stents (DES) has been driven by many technological advances and large bodies of clinical trial evidence. The journey to present day practice has seen many setbacks, such as acute vessel closure with POBA; rates of instant restenosis with bare metal stents (BMS) and more recently, high rates of stent thrombosis with bioabsorbable platforms. This work discusses POBA, why there was a need for BMS, the use of inhibiting drugs to create 1^st generation DES, the change of components to 2^nd generation DES, the use of absorbable drug reservoirs and platforms, and possible future directions with Prohealing Endothelial Progenitor Cell Capture Stents. Expert commentary: This paper reviews the evolution from the original pioneering work to modern day practice, highlighting landmark trials that changed practice. Modern day contemporary practice is now very safe based on the latest drug eluting stents and supported by large datasets.

Effectiveness and Safety of Biolimus A9™-Eluting stEnt in Patients with AcUTe Coronary sYndrome; A Multicenter, Observational Study (BEAUTY Study)

PURPOSE

This study sought to determine the 1-year clinical effectiveness and safety of a biodegradable, polymer-containing Biolimus A9™-eluting stent (BES) in Korean patients with acute coronary syndrome (ACS).

MATERIALS AND METHODS

A total of 1000 ACS patients with 1251 lesions who underwent implantation of BESs at 22 centers in Korea were enrolled between May 2011 and July 2013. We assessed major adverse cardiac events (MACE) defined as the composite of cardiac death, non-fatal myocardial infarction (MI), and clinical-driven target vessel revascularization at 12 months.

RESULTS

Patient mean age was 62.6±11.4 years. 72.8% of the patients were male, 28.5% had diabetes, 32.8% had multi-vessel disease (MVD), and 47.9% presented with acute MI (AMI). The mean global registry of acute coronary events risk score of all patients was 103.0±27.6. The number of stents per patient was 1.3±0.6. The incidences of MACE and definite stent thrombosis at 12 months were 3.9% and 0.2%, respectively. On multivariate Cox-regression analysis, age ≥65 years was identified as an independent predictors of 1-year MACE (hazard ratio=2.474; 95% confidence interval=1.202-5.091). Subgroup analyses revealed no significant differences in the incidence of MACE between patients with and without diabetes (4.3% vs. 3.7%, p=0.667), between those who presented with and without AMI (4.4% vs. 3.4%, p=0.403), and between those with and without MVD (4.6% vs. 3.5%, p=0.387).

CONCLUSION

Our study demonstrated excellent 1-year clinical outcomes of BES implantation in patients at low-risk for ACS.

Technical factors affecting outcomes following endovascular treatment of posterior circulation atherosclerotic lesions

Background

Atherosclerotic disease of the vertebrobasilar system causes significant morbidity and mortality. All lesions require aggressive medical management, but the role of endovascular interventions remains unsettled. This study examines such endovascular interventions for vertebrobasilar atherosclerosis.

Methods

Retrospective review was performed of prospectively maintained procedure logs at three hospitals with comprehensive neurointerventional services. Patients with angiographically-proven stenosis undergoing elective stent placement were selected for analysis of demographic factors, lesion characteristics, and treatment details. Multivariate analysis was performed to evaluate for associations with ischemic stroke, death, and functional status as measured by modified Rankin scale at multiple intervals.

Results

One hundred and twenty-three lesions were treated in 110 patients. A total of 43 (58.1%) lesions caused stroke, while 66 (89.2%) caused transient ischemic attacks (TIAs). Forty lesions (32.5%) were at the vertebral origin; 97 (60.2%) were intracranial. A total of 112 (91.1%) were treated successfully. 4 (3.3%) of 10 (8.1%) procedural complications were symptomatic. Intracranial lesions were associated with death at 1 and 2 years (OR 24.91, P < 0.001) and mRS >2 at last contact (OR 12.83, P < 0.001). Stenting treatment with conjunctive angioplasty had lower rates of death (OR 0.303, P = 0.046) and mRS >2 at last contact (OR 0.234, P = 0.018) when angioplasty was performed with a device other than that packaged with the stent.

Conclusion

Endovascular treatment of vertebrobasilar atherosclerosis can be performed safely, particularly for vertebral origin lesions. Higher rates of technical failure and complication may be acceptable for certain intracranial lesions due to their refractory nature and the morbidity caused by such lesions. Treatment should be tailored to features of each individual lesion.

Time course, predictors and clinical implications of stent thrombosis following primary angioplasty

Primary percutaneous coronary intervention (pPCI) has improved survival as compared to thrombolysis. Concerns still remain regarding the risk of stent thrombosis in the setting of STEMI, especially after drugeluting stent (DES) implantation. Therefore, the aim of this study was to report on the timing of stent thrombosis (ST) with both DES and bare metal stents (BMS) and its prognostic significance in patients undergoing pPCI. The Drug-Eluting Stent in Primary Angioplasty (DESERT) cooperation is based on a pooled database including individual data of randomised trials that evaluate the long-term safety and effectiveness of DES as compared to BMS in patients undergoing pPCI for STEMI. Follow-up data were collected for 3–6 years after the procedure. ST was defined as definite or probable, based on the ARC definition. The study population consists of 6,274 STEMI patients undergoing primary angioplasty with BMS or DES. At 1201±440 days, ST occurred in 267 patients (4.25%). Most of the events were acute or subacute (within 30 days) and very late (> 1 years), with different distribution between DES vs BMS. Patients with ST were more often diabetic (21.7% vs 15.1%, p=0.005), more frequently had post-procedural TIMI 0–2 flow (14.0% vs 9.3%, p = 0.01), and were less often treated with dual antiplatelet therapy at one year follow-up. Diabetes (p = 0.036), post-procedural TIMI 0–2 Flow (p = 0.013) and ischaemia time > 6 hours (p = 0.03) were independent predictors of ST. Post-procedural TIMI 0–2 flow (p = 0.001) and ischaemia time > 6 hours (p < 0.001) were independent predictors of early ST, ischaemia time > 6 hours (p=0.05) was independent predictor of late ST, whereas diabetes (p = 0.022) and use of DES (p=0.002) were independent predictors of very late ST. ST was associated with a significantly higher mortality (23.6% vs 6%, p < 0.001). The greatest impact on mortality was observed with subacute (40.4%) and late (20.9%) ST, as compared to acute (12.5%) and very late (9.1%) ST. ST was an independent predictor of mortality (HR [95%CI]=3.73 [2.75–5.07], p < 0.001). In conclusion, ST occurs relatively frequently also beyond the first year for up to six years after pPCI in STEMI, with higher late occurrence rates among patients treated with first generation DES. ST after pPCI is a powerful predictor of mortality, especially subacute ST.

The impact of acute coronary syndrome on late drug-eluting stents restenosis: Insights from optical coherence tomography

The aim of the study was to investigate the optical coherence tomography (OCT)-identified difference of in-stent restenosis (ISR) tissue characteristics between patients with and without acute coronary syndrome (ACS) at index intervention.The retrospective study included 80 patients with 85 drug-eluting stent (DES) restenosis lesions. Subjects were classified according to clinical presentation at the time of de-novo lesion intervention, namely ACS and non-ACS. OCT was performed at 5 years follow-up. The frequency of malapposition, neointimal characteristics, thrombus, and minimal stent area (MSA) were evaluated.ACS group consisted of 48 (60%) patients. The mean duration from initial intervention to OCT study was 66.15 months. Malapposition was more frequent in the ACS group (25.5% vs 2.9%, P = .006), as well as a higher prevalence of thrombus in the ACS group (21.6% vs 0%, P = .015). MSA of ACS group was significantly less than that of non-ACS group (4.99 ± 1.80 vs 5.62 ± 2.08 mm, P = .018). Compared with non-ACS group, only MI group was related to smaller MSA (4.37 ± 1.39 vs 5.62 ± 2.08 mm, P = .048); The unstable angina (UA) group was not associated with a decreased MSA. The occurrence of neoatherosclerosis tended to be higher in ACS group (60.8% vs 41.2%, P = .076).In DES restenosis, an ACS presentation at initial intervention is associated with a higher incidence of malapposition, thrombus, and smaller MSA.

Histopathological comparison of biodegradable polymer and permanent polymer based sirolimus eluting stents in a porcine model of coronary stent implantation

Biodegradable stent coatings were recently introduced as a potential solution to overcome sustained inflammatory responses observed with permanent polymer-based drug-eluting stents. In a preliminary study, selected biodegradable or permanent polymer-based sirolimus-eluting stent (SES) formulations were screened for effectiveness in comparison to bare metal stents (BMS) at 28 days. Subsequently, the most favourable SES formulation was compared to commercially available SES (CypherTM) at 28,90 and 180 days to investigate the histopathologic response as well as tissue, blood and organ pharmacokinetics. Overlapping SES implantation was conducted to evaluate vascular healing at 28 days in this particular setting. SES with biodegradable poly (L-lactide) polymer (PLLA) or poly(lactide-co-glycolide) showed the most favourable outcome with regards to reductions in neointimal area in comparison to BMS at 28 days. The PLLA SES showed a similar reduction in neointimal area compared to CypherTM at 28 days, with significant greater reductions at 90 and 180 days (1.7 ± 0.7 mm2 vs. 3.1 ± 1.5 mm2, p=0.03 and 1.8 ± 1.2 mm2 vs. 3.0 ± 1.5 mm2, p=0.01, respectively). Sirolimus vascular tissue concentrations were detectable up to 90 days following implantation. Overlapping stented segments showed favourable histopathologic results with respect to fibrin deposition and endothelialisation at 28 days. In conclusion, the use of PLLA as drugeluting matrix resulted in mild inflammatory responses in the presence of effective sirolimus tissue concentrations. The greater efficacy observed at long-term follow-up in PLLA SES compared to CypherTM may be a multifactorial result of stent design, polymer biocompatibility and improved release kinetics.

Failure Mechanisms and Neoatherosclerosis Patterns in Very Late Drug-Eluting and Bare-Metal Stent Thrombosis

BACKGROUND

There are few clinical studies on the pathophysiological mechanisms of very late stent thrombosis (VLST). We report optical coherence tomography findings in patients with VLST and compare the findings between bare-metal stents (BMS) and drug-eluting stents (DES).

METHODS AND RESULTS

We conducted a registry of stent thrombosis at 4 North American centers with optical coherence tomography imaging programs SAFE registry (The Study of Late Stent Failure Evaluated by OCT). Images were acquired in 61 patients (42 DES and 19 BMS) presenting with definite VLST. The median duration from implantation to VLST presentation was 51.4 months in the DES and 69.9 months in the BMS group (P=0.011). Uncovered and malapposed struts were observed in 70.5% (43/61) and 62.3% (38/61) of patients, respectively, whereas neoatherosclerosis was revealed in 49.2% (30/61). Stent underexpansion was observed in 42.4% of patients. Malapposed struts and stent underexpansion were more frequently demonstrated in DES than in BMS patients, whereas neoatherosclerosis was frequently observed in BMS (40.5% in DES and 68.4% in BMS; P=0.056). The percentage of frames with neoatherosclerosis was lower in DES than in BMS (15.56% [12.24-28.57] versus, 56.41% [40.74-70.00], respectively; P<0.001). Maximum consecutive lipid neointima length was shorter in DES than in BMS (2.4 [1.2-3.6] and 5.3 [3.0-7.0] mm; P=0.011).

CONCLUSIONS

Optical coherence tomography imaging demonstrated that VLST in DES and BMS had a wide variety of abnormal findings, such as neoatherosclerosis, uncovered strut, and malapposed strut. Neoatherosclerosis and lipid neointima were more frequently observed and had more longitudinal extension in BMS compared with DES.

A comparison of the main outcomes from BP-BES and DP-DES at five years of follow-up: A systematic review and meta-analysis

Biodegradable polymer biolimus-eluting stents (BP-BES) are third-generation drug-eluting stents (DES) composed of biodegradable polymers that may improve prognosis after percutaneous coronary intervention (PCI). After five years of follow-up, BP-BES showed conflicting results compared to durable polymer drug-eluting stents (DP-DES). We performed a meta-analysis of the outcomes of studies on BP-BES and DP-DES after percutaneous coronary intervention (PCI) at five years of follow-up. Eligible studies were retrieved from PubMed, Embase and the Cochrane Library and reported the results of all-cause mortality, myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR) and stent thrombosis (ST) at five years of follow-up. Five studies of a total of 4687 patients were included in the meta-analysis. At five years of follow-up, BP-BES was associated with lower rates of major adverse cardiac events (MACE) (OR = 0.83, 95%CI = [0.71, 0.97]), TLR (OR = 0.77, 95%CI = [0.62, 0.96]) and ST (OR = 0.60, 95%CI = [0.43 to 0.84]), whereas no significant differences in mortality, MI, or TVR rates were detected. Our results demonstrated that at five years of follow-up, BP-BES can significantly reduce the risk of MACE, TLR and ST, which indicate that safety and efficacy were increased after PCI.

Impact of lesion complexity on long-term vascular response to cobalt-chromium everolimus-eluting stent: five-year follow-up optical coherence tomography study

The impact of lesion complexity on long-term vascular response to cobalt-chromium everolimus-eluting stent (CoCrEES) remains unclear. We sought to evaluate them using optical coherence tomography (OCT). A total of 47 patients with 58 lesions treated only with CoCrEES and no target-vessel events within 5 years after implantation were prospectively enrolled and underwent 5-year follow-up OCT. Quantitative parameters and qualitative characteristics of the neointima were evaluated using multilevel logistic or linear regression models with random effects at three levels: lesion, cross-section (CS), and strut. According to the lesion complexity, the lesions were classified into the two groups: the complex lesion (CL) and non-CL group. The CL was defined as having at least 1 high-risk feature such as acute coronary syndrome lesion, lesion length > 20 mm, severe calcification requiring rotational atherectomy, and chronic total occlusion at the index procedure. A total of 11,034 struts (CL, n = 6240; non-CL, n = 4794) and 1202 (CL, n = 683; non-CL, n = 519) CSs were analyzed. The percentage of uncovered and malapposed struts did not differ significantly between the CL and non-CL groups (0.90 vs. 0.54%, P = 0.78; 0.56 vs. 0.10%, P = 0.16, respectively). The incidence of neoatherosclerosis was comparable between both groups in the CS- and lesion-level analysis (3.5 vs. 4.6%, P = 0.91; 32.0 vs. 24.2%, P = 0.52, respectively). At 5 years, CoCrEES shows an excellent vascular healing and similar frequency of neoatheroslerosis in patients without target-vessel events, regardless of the lesion complexity.