Neointimal Volume Research Articles

First in human evaluation of the vascular biocompatibility and biomechanical performance of a novel ultra high molecular weight amorphous PLLA bioresorbable scaffold in the absence of anti-proliferative drugs: Two-year imaging results in humans.

In this first-in-human study, we prospectively studied the vascular compatibility and mechanical performance of a novel bare ultra-high molecular weight amorphous PLLA bioresorbable scaffold (BRS, FORTITUDE®, Amaranth Medical, Mountain View, California) up to two years after implantation using multimodality imaging techniques. The vascular biocompatibility of polymers used in BRS has not been fully characterized in the absence of anti-proliferative drugs. A total of 10 patients undergoing single scaffold implantation were included in the final analysis and were followed up using optical coherence tomography (OCT) at 2-years. All devices were implanted under angiographic and intravascular ultrasound (IVUS) guidance. Angiographic and IVUS follow up was performed at 6 months. Additionally, angiography and OCT imaging were performed at 2-years. At 6 months, mean intra-scaffold angiographic MLD slightly decreased from baseline procedural values. However, at 2 years, mean angiographic MLD increased (post procedure; 2.9 [2.7, 3.1] mm vs. 6 months; 2.1 [1.6, 2.5] vs. 2 years; 2.4 [2.1, 2.6], P = .001). Also, angiographic percent diameter stenosis decreased and late lumen gain increased between 6 months and 2 years follow up. Mean neointimal hyperplasia volume assessed by IVUS at 6 months was 26% [15.2, 29.3]. At 2 years OCT follow up neointimal hyperplasia volume was 24.2% [19.4, 28.9]. No presence of neoatherosclerosis was identified in any of the analyzed cases. At 2 years, this novel PLLA-based BRS induced expansive vascular remodeling from 6 to 24 months, a biological phenomenon that appears to be independent of the presence of anti-proliferative drugs.

An optical coherence tomography study of neointimal morphology and strut coverage at different time intervals from implantation of biodegradable polymer-coated sirolimus-eluting stents.

The aim of the study was to capture the evolution of neointima after implantation of a biodegradable polymer-coated, sirolimus-eluting, cobalt-chromium coronary stent system (BP-DES). Optical coherence tomography (OCT) suggests that in-stent neointimal morphology influences clinical outcomes after DES implantation. Sixty patients treated with single BP-DES implantation were examined by quantitative coronary angiography (QCA) and OCT at 3, 6, and 12-month follow-up. Median late lumen loss by QCA (mm) was 0.04 (IQR 0, 0.08), 0.17 (IQR 0, 0.32), and 0.14 (IQR 0.07, 0.31) at 3, 6, and 12-month follow-up respectively (P = 0.03). OCT cross-section multilevel analysis showed uncovered struts in 3.90%, 1.78%, and 0.02% of struts respectively (P = 0.03). The corresponding malapposition rates were 0.12%, 0.04%, and 0%. Lipid-rich neointima was observed only at 12-month follow-up in one restenotic lesion (0.77% cross-sections) that was accountable for the only target vessel revascularization. The homogeneous pattern was prevalent at all three time points, but its incidence displayed an upward trend (3 months: 59%; 6 months: 71%; 12 months: 88%) despite no difference in neointimal volume between 6 and 12 months. Conversely, a trend could be observed of decreasing incidence of heterogeneous pattern as the follow-up length increased. In this study of a single-type BP-DES, the majority of stent struts were covered within 3 months from implantation. While the quantitative neointimal accumulation plateaued at 6 months with no further significant increase beyond 6 months, the neointima continued to evolve qualitatively and mature along with better strut coverage between 6 and 12 months after implantation.

Comparative assessment of three drug eluting stents with different platforms but with the same biodegradable polymer and the drug based on quantitative coronary angiography and optical coherence tomography at 12-month follow-up

The aim of this study was to compare neointima proliferation in three drug-eluting stents (DES) produced by the same company (Balton, Poland) which are covered with a biodegradable polymer and elute sirolimus (concentration: 1.0 and 1.2 µg/mm2), but have different stent platforms and strut thickness: stainless steel Prolim® (115 µm) and BiOSS LIM® (120 µm) and cobalt-chromium Alex® (70 µm). We analyzed data of patients with quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 12 months from BiOSS LIM Registry, Prolim Registry and Alex OCT clinical trial. There were 56 patients enrolled, in whom 29 Prolim® stents were deployed, in 11—BiOSS LIM® and in 16—Alex stents. The late lumen loss was the smallest in Prolim® subgroup (0.26 ± 0.17 mm) and did not differ from Alex® subgroup (0.28 ± 0.47 mm). This parameter was significantly bigger in BiOSS® subgroup (0.38 ± 0.19 mm; p < 0.05). In OCT analysis there was no statistically significant difference between Prolim® and Alex® subgroups in terms of mean neointima burden (24.6 ± 8.6 vs. 19.27 ± 8.11%) and neointima volume (28.16 ± 15.10 vs. 24.51 ± 17.64 mm3). In BiOSS® group mean neointima burden (30.9 ± 6.2%) and mean neointima volume (44.9 ± 4.9 mm3) were significantly larger. The morphological analysis revealed that in most cases in all groups the neointima was homogenous with plaque presence only around stent struts. In the QCA and OCT analysis regular DES (Prolim® and Alex®) obtained similar results, whereas more pronounced response from the vessel wall was found in the BiOSS® subgroup.

5-Lipoxygenase in monocytes emerges as a therapeutic target for intimal hyperplasia in a murine wire-injured femoral artery

Given the importance of leukotrienes in vascular inflammation induced by local tissue injury, this study investigated the role for 5-lipoxygenase (5-LO) in monocytes in the development of intimal hyperplasia. As a mechanistic study, the importance of monocyte 5-LO in monocyte-macrophage differentiation with subsequent infiltration in neointima was evaluated. In a mouse model of wire-injured femoral artery, intimal hyperplasia started as early as 2wks after injury, and luminal area and blood flow were reduced due to increased neointima formation. Time-dependent increases in macrophage infiltration were observed in neointima and showed a positive relationship with neointima volume. In 5-LO-deficient (KO) mice or wild-type (WT) mice treated with an inhibitor of 5-LO activating protein (MK886, 1 and 10mg/kg), intimal hyperplasia and macrophage infiltration into neointima were reduced, but monocyte adhesion to injured luminal surface was not inhibited, which suggested 5-LO participates in monocyte-macrophage differentiation. In an in vitro study, monocyte-macrophage differentiation was found to be increased by high mobility group box 1 protein (HMGB1), but this effect was attenuated in cells isolated from 5-LO-KO mice. Furthermore, macrophage infiltration and intimal hyperplasia were more prominent in 5-LO-KO mice transplanted with monocytes from WT mice than in 5-LO-KO mice transplanted with monocytes from 5-LO-KO mice. Taken together, it was suggested that 5-LO in monocytes played a pivotal role in monocyte-macrophage differentiation and subsequent infiltration of macrophage in neointima, leading to vascular remodeling after vascular injury.

Analysis of neointima development in flow diverters using optical coherence tomography imaging

BackgroundFlow diverters are used for the treatment of intracranial aneurysms. Surface modification may decrease the thrombogenicity of flow diverters but the details are unknown. Optical coherence tomography (OCT) is an...

Biological effect of microengineered grooved stents on strut healing: a randomised OCT-based comparative study in humans

ObjectiveTo evaluate the biological effect of microengineered stent grooves (MSG) on early strut healing in humans by performing optical coherence tomography (OCT) analysis 3 weeks following the implantation.BackgroundIn the experimental...

Impact of attenuated-signal plaque observed by intravascular ultrasound on vessel response after drug-eluting stent implantation

Background and aimsThe aim of this study was to investigate the impact of attenuated-signal plaque (ASP) observed by intravascular ultrasound (IVUS) on vessel response after drug-eluting stent implantation. MethodsData were derived from the IVUS cohort of the J-DESsERT trial comparing paclitaxel- and sirolimus-eluting stents. Serial IVUS analysis (pre- and post-intervention, and 8-month follow-up) was performed in 136 non-AMI lesions. ASP was defined as hypoechoic plaque with ultrasound attenuation without calcification. Calcified plaque (CP) was defined as brightly echoreflective plaque with acoustic shadowing. ASP and CP scores were calculated by grading their measured angle as 0 to 4 for 0°, <90°, 90–180°, 180–270° and >270°, respectively. The entire stented segment was analyzed at 1-mm intervals. ResultsAt pre-intervention, ASP was observed in 40.4% of lesions, and this group had greater % neointimal volume (%NIV) at follow-up than the no-ASP group (p = 0.011). ASP score at pre-intervention positively correlated with %NIV (p = 0.023). During the follow-up, ASP score significantly decreased (p < 0.001), and CP score significantly increased (p < 0.001), with a negative correlation between them (p < 0.001). A decrease in the ASP score was associated with less %NIV in PES (p = 0.031), but not in SES (p = 0.229). ConclusionsThe greater extent of plaque with IVUS-signal attenuation at pre-intervention and its persistence during follow-up were associated with neointimal proliferation, possibly representing sustained inflammatory status, depending on the type of DES used.

Prospective randomized comparison of clinical and angiographic outcomes between everolimus-eluting vs. zotarolimus-eluting stents for treatment of coronary restenosis in drug-eluting stents: intravascular ultrasound volumetric analysis (RESTENT-ISR trial).

At present no proven standard treatment for drug-eluting stent (DES) restenosis is available, and the efficacy and safety of everolimus-eluting stent (EES) and zotarolimus-eluting stent (ZES) for DES restenosis are limited. The purpose of this prospective, randomized 9-month intracoronary ultrasound (IVUS) and 3-year clinical follow-up study was to compare the effects of EESs and ZESs on neointima volume and major adverse cardiovascular events (MACEs) such as death, myocardial infarction (MI), target lesion revascularization (TLR) and stent thrombosis in DES restenosis patients. Patients were eligible for this study if they were between 40 and 75 years old with in-stent restenosis >50% by quantitative coronary angiographic analysis in DES or within 5 mm of the stent edges with signs of ischaemia. Eligible patients (n = 304, 146 women and 158 men) were randomly assigned to receive either EES (158 patients) or ZES (146 patients). The primary endpoint of the study was to compare neointima volume between the EES and ZES groups at the 9-month follow-up IVUS. MACEs, including death, non-fatal MI, stent thrombosis and the need for repeated TLR within 3 years, were noted. The 9-month angiographic and IVUS follow-up showed no significant differences in late lumen loss (0.40 ± 0.56 vs. 0.45 ± 0.61 mm, P = 0.57, respectively) and neointima volume (0.51 ± 0.48 vs. 0.56 ± 0.54 mm3/1 mm, P = 0.47, respectively) in the EES and the ZES groups. Composite MACEs such as death, MI, stent thrombosis and TLR during 3-year follow-up were comparable between the two groups [15.8% (n = 25) in the EES group and 22.6% (n = 33) in the ZES group, P = 0.276], independent of de novo DES type, sex, age, body mass index, presence of diabetes, hypertension and dyslipidaemia. Patients with first- and second-generation DES restenosis, both EES and ZES implantation were effective and safe in reducing neointima volume and late loss with a comparable rate of MACEs independent of cardiovascular risk factors.

Evaluation of vascular healing of polymer-free sirolimus-eluting stents in native coronary artery stenosis: a serial follow-up at three and six months with optical coherence tomography imaging

Our aim was to assess vascular response after polymer-free sirolimus-eluting stent (SES) implantation by using an optical coherence tomography (OCT)-derived vascular healing score (HS), quantifying the deficiency of healing. In a prospective, multicentre, single-arm, open-label study, OCT examinations were performed at three months in 45 patients (47 lesions). Per protocol, 24 lesions which had not reached adequate vascular healing according to study criteria were scheduled for OCT examination at six months. The HS was calculated at two time points. Serial OCT imaging demonstrated that the proportion of covered stent struts increased from a median of 87.1% at three months to 98.6% at six months (p<0.001). The neointimal thickness increased from a median of 82.8 µm to 112.2 µm (p<0.001), whereas the median percentages of malapposed struts were 0.2% and 0.0% at the two respective time points. Neointimal volume obstruction increased from 6.3% to 12.8%, and the HS decreased from a median of 28.1 at three months to 2.4 at six months. In patients who had inadequate vascular healing three months after polymer-free SES implantation, serial OCT showed almost complete vascular healing at six months.

Effect of Pioglitazone in Preventing In-Stent Restenosis after Percutaneous Coronary Intervention in Patients with Type 2 Diabetes: A Meta-Analysis.

BackgroundThe benefits of pioglitazone in patients with type 2 diabetes mellitus (T2DM) after percutaneous coronary intervention (PCI) is unclear.ObjectivesTo evaluate the effect of pioglitazone on prevention of in-stent restenosis (ISR) in patients with T2DM after PCI.MethodsAll full-text published relevant studies compared the effect of pioglitazone with control group (placebo or no pioglitazone treatment) on ISR in patients with T2DM after PCI were identified by searching the databases including PubMed, EMBASE, Cochrane Library and ISI Web of Science through October 2015. The endpoints were defined as the rate of ISR, late lumen loss, in-stent neointimal volume, target lesion revascularization (TLR) and major adverse cardiac events (MACE).ResultsSix studies (5 RCTs and 1 retrospective study), comprising 503 patients, were included into this meta-analysis. In the pioglitazone group, as compared with the control group, the risk ratio for ISR was 0.48 (I2 = 14.5%, P = 0.322; 95%CI 0.35 to 0.68, P<0.001), the risk ratio for TLR was 0.58 (I2 = 6.0%, P = 0.363; 95%CI 0.38 to 0.87, P = 0.009). The result showed there was no association between the use of pioglitazone and the events of MACE (I2 = 36.7%, P = 0.209; RR 0.56, 95%CI 0.30 to 1.05, P = 0.071). For the considerable heterogeneity, further analysis was not suitable for the endpoints of late lumen loss (I2 = 81.9%, P<0.001) and neointimal volume (I2 = 75.9%, P = 0.016).ConclusionsThe treatment of pioglitazone was associated with a reduction in ISR and TLR in T2DM patients suffering from PCI, except the incidence of MACE.

Effect of n-3 Polyunsaturated Fatty Acids on Regression of Coronary Atherosclerosis in Statin Treated Patients Undergoing Percutaneous Coronary Intervention.

Background and ObjectivesStatins remain the mainstay of secondary coronary artery disease (CAD) prevention, but n-3 polyunsaturated fatty acids (ω-3 PUFA) display biological effects that may also reduce the risk of atherosclerosis and CAD. However, data on the possible antiatherosclerotic benefits of adding ω-3 PUFA to statin therapy are limited. This study aimed to investigate the potential additive effects of ω-3 PUFA on regression of atherosclerosis in CAD patients receiving statin therapy and stent implantation.Subjects and MethodsSeventy-four CAD patients undergoing percutaneous coronary intervention (PCI) with stent implantation were enrolled, prescribed statins, and randomly assigned to two groups: n-3 group (ω-3 PUFA 3 g/day, n=38) or placebo group (placebo, n=36). All patients completed the study follow-up consisting of an intravascular ultrasound at baseline and at 12 months.ResultsThere was no difference in the baseline characteristics and distribution of other medications. No significant differences were observed in primary endpoints, including changes in atheroma volume index (−12.65% vs. −8.51%, p=0.768) and percent atheroma volume (−4.36% vs. −9.98%, p=0.526), and in secondary endpoints including a change in neointimal volume index (7.84 vs. 4.94 mm3/mm, p=0.087).Conclusionω-3 PUFA had no definite additional effect on the regression of coronary atherosclerosis when added to statin in CAD patients undergoing PCI.

Neointimal response to second-generation drug-eluting stents in diabetic patients with de-novo coronary lesions: intravascular ultrasound study.

The aim of this study was to evaluate the extent of neointimal response after the implantation of a second-generation drug-eluting stent, zotarolimus-eluting stent (ZES-ER, Endeavor Resolute) or everolimus-eluting stent (EES, Xience V), using intravascular ultrasound (IVUS) in diabetic patients. In all, 154 diabetic patients with de-novo coronary lesions were randomized to be implanted with a ZES-ER or EES, and the angiographic follow-up at 9 months combined with a complete IVUS study was available for 96 patients with 101 lesions. Baseline demographic and lesion parameters were similar in both groups at index percutaneous coronary intervention. On follow-up angiography, in-stent late lumen loss and minimal lumen diameter were not different between the two groups. On IVUS study, neointimal hyperplasia volume [median (interquartile range): ZES-ER vs. EES; 2.25 mm (0.57-6.25) vs. 1.59 mm (0.45-8.37), P=0.615] and in-stent percentage of volume obstruction [median (interquartile range): ZES-ER vs. EES; 1.16% (0.33-3.61) vs. 0.77% (0.29-4.01), P=0.615] showed similar results between the two groups. In diabetic patients, the second-generation drug-eluting stents, ZES-ER and EES, were comparable in inhibiting neointimal proliferation.

Reliable femoral chronic total occlusion model using a thin biodegradable polymer coated copper stent in a porcine model.

Chronic total occlusions (CTOs) are common in patients with peripheral arterial disease (PAD). This study aimed to examine the feasibility and reliability of a CTO induced by a thin biodegradable polymer (polyglycolic acid) coated copper stent in a porcine femoral artery. Novel thin biodegradable polymer coated copper stents (9 mm long) were crimped on an angioplasty balloon (4.5 mm diameter × 12 mm length) and inserted into the femoral artery. Histopathologic analysis was performed 35 days after stenting. In five of six stented femoral arteries, severe in-stent restenosis and total occlusion with collateral circulation were observed without adverse effects such as acute stent thrombosis, leg necrosis, or death at 5 weeks. Fibrous tissue deposition, small vascular channels, calcification, and inflammatory cells were observed in hematoxylin-eosin, Carstair's, and von Kossa tissue stains; these characteristics were similar to pathological findings associated with CTOs in humans. The neointima volume measured by micro-computed tomography was 93.9 ± 4.04 % in the stented femoral arteries. CTOs were reliably induced by novel thin biodegradable polymer coated copper stents in porcine femoral arteries. Successful induction of CTOs may provide a practical understanding of their formation and application of an interventional device for CTO treatment.

Pioglitazone increases circulating microRNA-24 with decrease in coronary neointimal hyperplasia in type 2 diabetic patients- optical coherence tomography analysis.

Aberrant expression of microRNAs is associated with neointimal hyperplasia (NIH) in type 2 diabetes. We prospectively compared the effects of pioglitazone on coronary NIH and changes in microRNAs according to NIH status in type 2 diabetic patients during 9-month follow-up. Type 2 diabetic patients were randomly assigned to the pioglitazone (n=36) or control groups (n=36) after coronary stenting. Primary endpoint was the comparison of changes in neointimal volume on OCT and in the level of circulating microRNA-17,-24,-92a,-126 and -145 during 9-month follow-up. Secondary endpoint was the comparison of changes in brachial artery flow-mediated dilation and inflammatory markers such as IL-6, TNF-α, hsCRP, adiponectin, sICAM-1, and sVCAM-1 between the 2 groups. Neointimal volume was significantly lower in the pioglitazone group (25.02±17.78 mm(3)vs. 55.10±30.01 mm(3), P<0.001) with significant increases in circulating microRNA-24 (0.264±0.084 vs. 0.006±0.030, P<0.001) during follow-up. FMD was significantly greater in the pioglitazone than control group at 9 months (0.47±0.14 mm vs. 0.28±0.18 mm, P<0.05, respectively). Decreases in inflammatory markers such as IL-6, TNF-α, and sVCAM-1 were significantly greater in the pioglitazone than the control group during the follow-up. Pioglitazone significantly decreased NIH with increases in circulating microRNA-24 at 9-month follow-up. The decrease in microRNA-24 could be used as a potential predictor of increases in NIH in type 2 diabetic patients.

Abstract 11963: Randomized Ivus Comparison Between a Durable and a Biodegradable-Polymer Second Generation Drug-Eluting Stents: The Bioactive Trial

Background: New generation drug-eluting stents (DES), biolimus-eluting stents (BES) and everolimus-eluting stents (EES) were conceived to minimize local coronary inflammation allowing better endothelial healing. The aim of this study is to compare the IVUS patterns observed with both stents at midterm follow-up. Methods: The Bioactive trial is a multicentre, randomized trial (1:1) comparing BES and EES based on surrogate safety and efficacy endpoints. Inclusion criteria was single, de novo lesions in native coronary arteries of 3.0 to 3.5mm and maximum lesion length of 20 mm. Patients with in-stent restenosis, lesion in grafts and treated in the setting of STEMI were excluded. The present analysis aims to compare the main IVUS findings for both DES at 9-month invasive follow-up. IVUS analyses were performed in an independent corelab blinded to the type of DES used. Results: A total of 40 patients were enrolled in the trial and 35 had IVUS performed. Procedure success was achieved in all cases. Baseline clinical characteristics as well as reference vessel diameter and lesion length did not significantly differ between the 2 cohorts. At 9 month, QCA measured in stent late loss was also comparable (0.15±0.18mm for BES vs. 0.20±0.47mm for EES, p=0.7). By IVUS, vessel volume (349±158mm3 for BES vs. 326±127mm3 for EES, p=0.6) and stent volume (178±78 for BESmm3 vs. 154±54mm3 for EES, p=0.4) did not significantly differ between the groups as well as neointimal tissue volume (3.6±2.8mm3 for BES vs 4.3±6.1mm3 for EES, p=0.4) and the % of stent obstruction (2.3±2.1% for BES vs. 2.5±2.8% for EES. OF note, the pattern of neointimal distribution was very similar between the two DES (figure). Conclusions: In this head-to-head to comparison, both second-generation DES were shown to be effective and safety in the treatment of coronary artery disease with no significant differences in terms of IVUS findings.

Dual role of circulating endothelial progenitor cells in stent struts endothelialisation and neointimal regrowth: a substudy of the IN-PACT CORO trial.

Endothelialisation is a crucial event after percutaneous coronary intervention (PCI). Endothelial progenitor cells (EPCs) are bone marrow derived elements with reparative properties. We aimed to assess the relationship between circulating EPC levels and stent neointimal hyperplasia (NIH) using frequency domain optical coherence tomography (FD-OCT). Patients undergoing elective PCI to native vessels and randomised to bare metal stent (BMS) alone versus BMS plus drug coated balloon (DCB) were included. At six months, angiographic follow-up and FD-OCT were performed to measure percentage neointimal hyperplasia volume obstruction (%NIHV), and percentage of uncovered stent struts (%US). Venous blood samples were obtained before the procedure and at six months to detect CD34+CD45dimKDR+ EPC levels. Twenty patients were enrolled. A significant relationship was observed between baseline EPC levels and %NIHV (R: 0.63, p: 0.03) and %US (R: -0.56, p: 0.01) at follow-up. Both EPC levels and DCB use were independently related to %NIHV (β: 0.55; p < 0.001 and β: -0.51; p: 0.001, respectively), while only EPC levels were independently associated to %US (β: -0.52; p: 0.01). Higher %NIHV (p: 0.004) and lower %US (p: 0.005) were observed in patients with stable or increasing EPC level. Our study shows a relationship between EPC levels and stent strut coverage, supporting a dual role for these cells in favouring stent endothelialisation but also NIH growth.

Mechanisms of balloon angioplasty and repeat stenting in patients with drug-eluting in-stent restenosis

BackgroundMechanisms of lumen gain during reinterventions in patients with drug-eluting stent (DES) in-stent restenosis (ISR) remain unsettled. MethodsWe sought to assess the mechanisms of acute lumen gain after balloon angioplasty (BA) and repeat drug-eluting stent (DES) implantation in patients with DES-ISR. Following a prospective protocol 29 consecutive patients with DES-ISR were sequentially treated with BA and new DES implantation under a multimodality intracoronary imaging assessment including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Imaging studies were systematically obtained, at baseline, after BA, and after DES. Results of interventions were compared using volumetric and morphometric (ISR pattern and injury score) analyses. ResultsIVUS and OCT demonstrated that acute lumen gain after BA and DES equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation not only increased final lumen (baseline 39.6±18.5mm3, post-BA 58.6±26.6mm3, post-DES 84.2±30.8mm3, all p<0.001) but also provided a smoother lumen (injury score 1.57±0.86 vs 0.22±0.26, p<0.001). At the 9th month of angiographic follow-up (86% patients) in-stent late loss was 0.44±0.5mm and 4 patients (16%) developed ISR. The ISR pattern on OCT was not associated with the injury score after interventions or late angiographic findings. Likewise, the injury score did not predict late angiographic outcome. ConclusionsIn patients with DES ISR, lumen gain equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation provides a larger and smoother coronary lumen.

Effect of pioglitazone on in-stent restenosis after coronary drug-eluting stent implantation: a meta-analysis of randomized controlled trials.

BackgroundIn-stent restenosis (ISR) remains a common life-threatening complication and some studies have shown that pioglitazone can reduce the incidence of ISR in patients with drug-eluting stents (DES) implantation. We conducted a meta-analysis to assess the effect of pioglitazone in preventing ISR after DES implantation.MethodsRandomized controlled trials (RCTs) investigating the effects of pioglitazone for ISR after DES implantation were identified by systematic searches of multiple online databases and manual searches of related reference lists of identified trials through May 2014. The primary endpoint was the rate of ISR. Secondary endpoints included minimum lumen diameter, percentage stenosis of stented vessels, late loss, in-stent neointimal volume, target vessel revascularization (TVR), target lesion revascularization, myocardial infarction, stent thrombosis and death.ResultsFive studies, comprising 255 pioglitazone-treated patients and 245 controls, were identified in the current meta-analysis. Pioglitazone did not significantly reduce the rate of ISR (P = 0.20) with low heterogeneity (I2 = 13.3%, P = 0.32). For the secondary outcomes, pioglitazone did not substantially affect the pooled estimates of these endpoints except late loss (P = 0.01) and TVR (P = 0.04).ConclusionsThe limited evidence indicates that pioglitazone does not demonstrate markedly beneficial effect in patients subjected to coronary DES implantation. However, the results should be interpreted with care given the small sample size. Further large-scale RCTs are needed.

Serial changes of neointimal tissue after everolimus-eluting stent implantation in porcine coronary artery: an optical coherence tomography analysis.

Purposes. The serial changes in neointimal tissues were compared between everolimus-eluting stent (EES) and bare-metal stent (BMS) in the porcine coronary artery using optical coherence tomography (OCT). Methods. Serial (1, 3, and 6 month follow-up after stent implantation) OCT examinations were performed in 15 swine with 15 BMS- and 15 EES-treated lesions in porcine coronary arteries. Results. In BMS-implanted lesions, neointimal volume decreased from 7.3 mm3 to 6.9 mm3 and 6.4 mm3 at 1, 3, and 6 months follow-up without statistical significance (P = 0.369). At the time points of 1, 3, and 6 months, neointimal tissue appearance was mainly a homogeneous pattern (80.0%, 93.3%, and 100%, resp.), while the other pattern was layered. In contrast, in EES-implanted lesions, neointimal volume significantly increased from 4.8 mm3 to 9.8 mm3 between 1 and 3 months but significantly decreased to 8.6 mm3 between 3 and 6 months (P < 0.001). Between 1 and 3 months, the layered pattern of neointimal tissue increased from 26.7% to 66.7% but decreased to 20.0% between 3 and 6 months. Conclusions. EES had a biphasic pattern of neointimal amounts that correlated with changes in neointimal morphology.

TCT-362 Relation between renal function and neointimal tissue characteristics after drug-eluting stent implantation: virtual histology-intravascular ultrasound analysis

Introduction: Patients with chronic kidney disease (CKD) had more mortality, myocardial infarction, repeat revascularization, and bleeding complication after percutaneous coronary intervention compared with those with patients with normal renal function. Hypothesis: It has been suggested that renal insufficiency may predict cardiovascular events due to an association with more severe coronary artery disease. However, few data are available about neointimal tissue characteristics according to the renal function after drug-eluting stent (DES) implantation. Therefore, the purpose of the present study was to attempt to assess the neointimal tissue components between patients with CKD and those without CKD using virtual histology-intravascular ultrasound (VH-IVUS). Methods: We compared neointimal tissue components between patients with CKD [n=19, estimated creatinine clearance (CrCl) Results: Mean follow-up durations between DES implantation and follow-up VH-IVUS study were 12.0±4.1 months in CKD group and 11.4±5.6 months in non-CKD group ( p = 0.519). At follow-up, neointima volume was significantly greater (72±47 mm 3 vs. 47±26 mm 3 , p p = 0.012) in CKD group compared with non-CKD group. There was negative correlation between CrCl and neointima volume ( r = -0.250, p r = -0.034, p = 0.591). Only independent predictor of follow-up %neointima NC volume ≥10% was neointima volume (odds ratio 1.025, 95% confidence interval 1.013-1.036, p Conclusions: Renal function was associated with in-stent neointimal growth, but it was not associated with neointima NC formation, instead the amount of neointima was associated with more neoatherosclerosis in patients who underwent DES implantation.