0165: Outcome after drug-eluting stents for cardiac allograft vasculopathy

PurposeCardiac allograft vasculopathy (CAV) constitues a primary cause of death after heart transplantation. Bare metal stents (BMS) have been used for revascularization, but they are associated with a high-risk of restenosis.Abstract 0474 – Figure: Kaplan-Meier estimates of one-year mortalityLimited data have shown favourable results with percutaneous coronary interventions (PCI) using drug-eluting stents (DES) in this specific population. Our study focuses on intra-stent restenosis (ISR) for DES in CAV, on new revascularisation and mortality.Methods97 consecutive heart transplant recipients with successful PCI were treated with DES (n=106) and BMS (n=25). They were prospectively followed-up at one year after PCI. An angiographic lesion-based analysis at 12-month follow-up and a patient-based survival analysis were performed.ResultsThe lesion-based analysis within 12 months after PCI showed an ISR rate with BMS of 12% and an ISR rate with DES of 3.8%. The target lesion revascularization (TLR) was 8% for BMS and 2.8% for DES. However, the target vessel revascularization was higher (16.5%) and the remote lesion revascularization was 8.7%, indicating the rapid occurrence of new significant lesions. Cardiac mortality at one year was 9.7% and extra- cardiac mortality was 2.9%.ConclusionsDES are associated with a low rate of TLR and can safely be used in heart transplant recipients with coronary artery disease. However, new significant lesions occurred at one year indicating a progression of CAV

Duration of Dual Antiplatelet Therapy Following Drug-Eluting Stent Implantation in Diabetic and Non-Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Diabetic patients account for an increasing number of patients undergoing percutaneous coronary intervention (PCI). However, diabetes mellitus (DM) is associated with increased residual platelet activity during dual antiplatelet treatment (DAPT) and DM patients have worse clinical outcomes after PCI as compared to non DM

Non-invasive imaging of atherosclerotic plaque macrophage in a rabbit model with F-18 FDG PET: a histopathological correlation

BACKGROUND: Coronary atherosclerosis and its thrombotic complications are the major cause of mortality and morbidity throughout the industrialized world. Thrombosis on disrupted atherosclerotic plaques plays a key role in the onset of acute coronary syndromes. Macrophages density is one of the most critical compositions of plaque in both plaque vulnerability and thrombogenicity upon rupture. It has been shown that macrophages have a high uptake of (18)F-FDG (FDG). We studied the correlation of FDG uptake with histopathological macrophage accumulation in atherosclerotic plaques in a rabbit model. METHODS: Atherosclerosis was induced in rabbits (n = 6) by a combination of atherogenic diet and balloon denudation of the aorta. PET imaging was performed at baseline and 2 months after atherogenic diet and coregistered with magnetic resonance (MR) imaging. Normal (n = 3) rabbits served as controls. FDG uptake by the thoracic aorta was expressed as concentration (μCi/ml) and the ratio of aortic uptake-to-blood radioactivity. FDG uptake and RAM-11 antibody positive areas were analyzed in descending aorta. RESULTS: Atherosclerotic aortas showed significantly higher uptake of FDG than normal aortas. The correlation of aortic FDG uptake with macrophage areas assessed by histopathology was statistically significant although it was not high (r = 0.48, p < 0.0001). When uptake was expressed as the ratio of aortic uptake-to-blood activity, it correlated better (r = 0.80, p < 0.0001) with the macrophage areas, due to the correction for residual blood FDG activity. CONCLUSION: PET FDG activity correlated with macrophage content within aortic atherosclerosis. This imaging approach might serve as a useful non-invasive imaging technique and potentially permit monitoring of relative changes in inflammation within the atherosclerotic lesion

Impact of structural features of very thin stents implanted in unprotected left main or coronary bifurcations on clinical outcomes

Objectives: To evaluate the independent clinical impact of stent structural features in a large cohort of patients undergoing unprotected left main (ULM) or coronary bifurcation percutaneous coronary intervention (PCI) with a range of very thin strut stents. Background: Clinical impact of structural features of contemporary stents remains to be defined. Methods: All consecutive patients enrolled in the veRy thin stents for patients with left mAIn or bifurcatioN in real life (RAIN) registry were included. The following stent structural features were studied: antiproliferative drugs (everolimus vs. sirolimus vs. zotarolimus), strut material (platinum-chromium vs. cobalt-chromium), polymer (bioresorbable vs. durable), number of crowns (<8 vs. ≥8) and number of connectors (<3 vs. ≥3). For small diameter stents (≤2.5 mm), struct thickness (74 vs. 80/81 μm) was also tested. Target lesion failure (TLF), a composite of target lesion revascularization and stent thrombosis, was the primary endpoint. Multivariate analysis was performed with Cox regression models. Results: Out of 2,707 patients, 110 (4.1%) experienced a TLF event after 16 months (12–18). After adjustment for confounders, an increased number of connectors (adjusted hazard ratio [adj-HR] 0.62, 95% confidence interval (CI) 0.39–0.99, p =.04) reduced risk of TLF, driven by stents with ≥2.5 mm diameter (HR 0.54, 95% CI 0.32–0.93, p =.02). This independent relationship was lost for stents with diameter <2.5 mm, where only strut thickness appeared to impact. Conversely, no independent relationship of polymer type, number of crowns, and the specific limus-family eluted drug with outcomes was observed. Conclusions: Among a range of contemporary very thin stent models, an increased number of connectors improved device-related outcomes in this investigated high-risk procedural setting

Dynamics of Membrane Trafficking Downstream of B and T Cell Receptor Engagement: Impact on Immune Synapses

The onset of an adaptive immune response requires the activation of T and B lymphocytes by antigen-presenting cells, through a specialized form of intercellular communication, known as the immunological synapse (IS). In B lymphocytes the IS promotes efficient recognition and acquisition of membrane-bound Ags, while in T cells, it modulates the T cell response upon exposure to peptide-major histocompatibility complexes. In this review, we highlight the similarities that determine B and T cell activation, focusing on immune receptor downstream signaling events that lead to synapse formation. We stress the notion that polarization of T and B lymphocytes characterized by global changes in cytoskeleton and membrane trafficking modulates synapse structure and function, thus determining lymphocyte effector functions and fate

Daily risk of adverse outcomes in patients undergoing complex lesions revascularization: a subgroup analysis from the RAIN-CARDIOGROUP VII study (veRy thin stents for patients with left mAIn or bifurcatioN in real life)

Introduction: Percutaneous coronary intervention (PCI) for complex lesions, including unprotected left main (ULM) and bifurcations, is gaining a relevant role in treating coronary artery disease with good outcomes, also thanks to new generation stents. The daily risk of adverse cardiovascular events and their temporal distribution after these procedures is not known.Methods: All consecutive patients presenting with a critical lesion of ULM or bifurcation treated with very thin struts stents, enrolled in the RAIN-Cardiogroup VII study, were analyzed. The daily risk of major acute cardiovascular events (MACE), target lesion revascularization (TLR) and stent thrombosis (ST) and their temporal distribution in the first year of follow-up was the primary endpoint. Differences among subgroups (ULM, patient presentation, kind of stent polymer) were the secondary endpoint.Results: 2745 patients were included, mean age 68 ± 11 years, 33.3% diabetics, 54.5% had an acute coronary syndrome (ACS); 88.5% of treated lesions were bifurcations, 27.2% ULM. Average daily risk was 0.022% for MACE, 0.005% for TLR and 0.004% for ST, in the first year. Bimodal distribution of adverse events, especially TLR, with an early peak in the first 50 days and a late one after 150 days, was observed. Patients with ULM presented a significantly higher daily risk of events, and ACS patients presented higher MACE risk. No difference emerged according to the type of stent polymer.Conclusions: The daily risk of adverse events in the first year after complex PCI in our study is acceptably low. PCI on ULM carries a higher risk of complications

Incidence of adverse events at 3 months versus at 12 months after dual antiplatelet therapy cessation in patients treated with thin stents with unprotected left main or coronary bifurcations

Incidence and predictors of adverse events after dual antiplatelet therapy (DAPT) cessation in patients treated with thin stents (<100 microns) in unprotected left main (ULM) or coronary bifurcation remain undefined. All consecutive patients presenting with a critical lesion of an ULM or involving a main coronary bifurcation who were treated with very thin strut stents were included. MACE (a composite end point of cardiovascular death, myocardial infarction [MI], target lesion revascularization [TLR], and stent thrombosis [ST]) was the primary endpoint, whereas target vessel revascularization (TVR) was the secondary endpoint, with particular attention to type and occurrence of ST and occurrence of ST, CV death, and MI during DAPT or after DAPT discontinuation. All analyses were performed according to length of DAPT dividing the patients in 3 groups: Short DAPT (3-months), intermediate DAPT (3 to 12 months), and long DAPT (12-months). A total of 117 patients were discharged with an indication for DAPT ≤3 months (median 1: 1 to 2.5), 200 for DAPT between 3 and 12 months (median 8: 7 to 10), and 1,958 with 12 months DAPT. After 12.8 months (8 to 20), MACE was significantly higher in the 3-month group compared with 3 to 12 and 12-month groups (9.4% vs 4.0% vs 7.2%, p ≤0.001), mainly driven by MI (4.4% vs 1.5% vs 3%, p ≤0.001) and overall ST (4.3% vs 1.5% vs 1.8%, p ≤0.001). Independent predictors of MACE were low GFR and a 2 stent strategy. Independent predictors of ST were DAPT duration <3 months and the use of a 2-stent strategy. In conclusion, even stents with very thin strut when implanted in real-life ULM or coronary bifurcation patients discharged with short DAPT have a relevant risk of ST, which remains high although not significant after DAPT cessation

Evidence of a causal and modifiable relationship between kidney function and circulating trimethylamine N-oxide

The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied "explainable" machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult Europeans of the MetaCardis study. Here we show that next to age, kidney function is the primary variable predicting circulating TMAO, with microbiota composition and diet playing minor, albeit significant, roles. Mediation analysis suggests a causal relationship between TMAO and kidney function that we corroborate in preclinical models where TMAO exposure increases kidney scarring. Consistent with our findings, patients receiving glucose-lowering drugs with reno-protective properties have significantly lower circulating TMAO when compared to propensity-score matched control individuals. Our analyses uncover a bidirectional relationship between kidney function and TMAO that can potentially be modified by reno-protective anti-diabetic drugs and suggest a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk

Imidazole propionate is increased in diabetes and associated with dietary patterns and altered microbial ecology

Microbiota-host-diet interactions contribute to the development of metabolic diseases. Imidazole propionate is a novel microbially produced metabolite from histidine, which impairs glucose metabolism. Here, we show that subjects with prediabetes and diabetes in the MetaCardis cohort from three European countries have elevated serum imidazole propionate levels. Furthermore, imidazole propionate levels were increased in subjects with low bacterial gene richness and Bacteroides 2 enterotype, which have previously been associated with obesity. The Bacteroides 2 enterotype was also associated with increased abundance of the genes involved in imidazole propionate biosynthesis from dietary histidine. Since patients and controls did not differ in their histidine dietary intake, the elevated levels of imidazole propionate in type 2 diabetes likely reflects altered microbial metabolism of histidine, rather than histidine intake per se. Thus the microbiota may contribute to type 2 diabetes by generating imidazole propionate that can modulate host inflammation and metabolism