Early vs. Late Readmission following Percutaneous Coronary Intervention: Predictors and Impact on Long-Term Outcomes.

BACKGROUND: Readmissions within 1 year after percutaneous coronary intervention (PCI) are common (18.6-50.4% in international series) and a burden to patients and health services, however their long-term implications are not well characterised. We compared predictors of 30-day (early) and 31-day to 1-year (late) unplanned readmission and the impact of unplanned readmission on long-term clinical outcomes post-PCI. METHODS: Patients enrolled in the GenesisCare Cardiovascular Outcomes Registry (GCOR-PCI) from 2008 to 2020 were included in the study. Multivariate logistic regression analysis was performed to identify predictors of early and late unplanned readmission. A Cox proportion hazards regression model was used to explore the impact of any unplanned readmission during the first year post-PCI on the clinical outcomes at 3 years. Finally, patients with early and late unplanned readmission were compared to determine which group was at the highest risk of adverse long-term outcomes. RESULTS: The study comprised 16,911 consecutively enrolled patients who underwent PCI between 2009-2020. Of these, 1422 patients (8.5%) experienced unplanned readmission within 1-year post-PCI. Overall, the mean age was 68.9 ± 10.5 years, 76.4% were male and 45.9% presented with acute coronary syndromes. Predictors of unplanned readmission included increasing age, female gender, previous CABG, renal impairment and PCI for acute coronary syndromes. Unplanned readmission within 1 year of PCI was associated with an increased risk of MACE (adjusted HR 1.84 (1.42-2.37), p < 0.001) and death over a 3-year follow-up (adjusted HR 1.864 (1.34-2.59), p < 0.001) compared with those without readmission within 1-year post-PCI. Late compared with early unplanned readmission within the first year of PCI was more frequently associated with subsequent unplanned readmission, MACE and death between 1 and 3 years post-PCI. CONCLUSIONS: Unplanned readmissions in the first year following PCI, particularly those occurring more than 30 days after discharge, were associated with a significantly higher risk of adverse outcomes, such as MACE and death at 3 years. Strategies to identify patients at high risk of readmission and interventions to reduce their greater risk of adverse events should be implemented post-PCI.

Myeloperoxidase modification of high-density lipoprotein suppresses human endothelial cell proliferation and migration via inhibition of ERK1/2 and Akt activation.

BACKGROUND AND AIMS: Preclinical studies show high-density lipoproteins (HDL) have a protective and reparative effect on the endothelium. HDL is, however, susceptible to oxidation, which affects function. Myeloperoxidase (MPO)-induced modification of HDL results in loss of anti-apoptotic and anti-inflammatory functions, however, its effect on endothelial proliferation and migration has not been characterized. METHODS: HUVECs were co-incubated with MPO-oxidised- or native-HDL (nHDL) in proliferation and migration assays. Signalling proteins were assessed in Western blots. RESULTS: nHDL caused dose-dependent increases of endothelial proliferation and migration. Consistent with an increase in cellular proliferation, HDL also stimulated proliferative cellular nuclear antigen (PCNA) expression and ERK phosphorylation in a concentration-dependent manner, which did not occur with MPO-oxidised HDL. HDL increased Akt phosphorylation, a driver of cellular migration. Contrastingly, MPO-oxidised HDL was unable to increase Akt phosphorylation and extensively-oxidised HDL inhibited Akt phosphorylation. CONCLUSIONS: HDL promotes endothelial proliferation and migration, mediated in part via activation of ERK and Akt signalling. MPO-induced oxidative modification of HDL attenuates the endothelial-protective effects of HDL. These findings suggest that in an oxidative milieu, present in ageing and disease, HDL is likely to become ineffective. This has implications for HDL-raising therapies and emphasizes the need for strategies that prevent oxidation-related HDL dysfunction.

High-density lipoproteins attenuate high glucose-impaired endothelial cell signaling and functions: potential implications for improved vascular repair in diabetes.

BACKGROUND: Abnormalities of endothelial cell function are proposed to be a critical factor underlying adverse cardiovascular outcomes in the setting of hyperglycaemia. While high-density lipoproteins (HDL) have been demonstrated to be cardioprotective, the impact on the endothelium in hyperglycaemia has not been fully elucidated. METHODS: Human umbilical vein endothelial cells (HUVECs) were exposed to high-glucose conditions using dextrose, the main isoform of glucose, and native HDL. HUVEC proliferation and migration were determined. The key signalling pathways that regulate endothelial cell function were also characterized. RESULTS: Increasing concentrations of dextrose resulted in significant reductions in HUVEC proliferation, this was attenuated by coincubation with HDL. In support of this, HDL was also found to rescue dextrose impaired expression of PCNA and the activation (phosphorylation) of the key transcription factor for proliferation ERK. Dextrose also dose-dependently inhibited HUVEC migration, which was mitigated by co-incubation with HDL. Consistent with this, HDL prevented dextrose-induced inhibition of p38 phosphorylation, responsible for cell migration. Finally, phosphorylation of the pro-survival transcription factor Akt was dose-dependently inhibited by dextrose, however, this was completely rescued by co-administration with HDL. CONCLUSION: Dextrose-induced hyperglycaemia causes the impairment of endothelial cell proliferation and migration and inhibits the activation of ERK, p38 and Akt pathways. The protective effects of HDL in this milieu highlights the potential for HDL to improve vascular repair in patients with impaired glucose homeostasis.

Combined therapy of dietary fish oil and stearoyl-CoA desaturase 1 inhibition prevents the metabolic syndrome and atherosclerosis.

BACKGROUND: Stearoyl-CoA desaturase 1 (SCD1) is a critical regulator of energy metabolism and inflammation. We have previously reported that inhibition of SCD1 in hyperlipidemic mice fed a saturated fatty acid (SFA)-enriched diet prevented development of the metabolic syndrome, yet surprisingly promoted severe atherosclerosis. In this study we tested whether dietary fish oil supplementation could prevent the accelerated atherosclerosis caused by SCD1 inhibition. METHODS AND RESULTS: LDLr(-/-), ApoB(100/100) mice were fed diets enriched in saturated fat or fish oil in conjunction with antisense oligonucleotide (ASO) treatment to inhibit SCD1. As previously reported, in SFA-fed mice, SCD1 inhibition dramatically protected against development of the metabolic syndrome, yet promoted atherosclerosis. In contrast, in mice fed fish oil, SCD1 inhibition did not result in augmented macrophage inflammatory response or severe atherosclerosis. In fact, the combined therapy of dietary fish oil and SCD1 ASO treatment effectively prevented both the metabolic syndrome and atherosclerosis. CONCLUSIONS: SCD1 ASO treatment in conjunction with dietary fish oil supplementation is an effective combination therapy to comprehensively combat the metabolic syndrome and atherosclerosis in mice.

Inhibition of stearoyl-coenzyme A desaturase 1 dissociates insulin resistance and obesity from atherosclerosis.

BACKGROUND: Stearoyl-coenzyme A desaturase 1 (SCD1) is a well-known enhancer of the metabolic syndrome. The purpose of the present study was to investigate the role of SCD1 in lipoprotein metabolism and atherosclerosis progression. METHODS AND RESULTS: Antisense oligonucleotides were used to inhibit SCD1 in a mouse model of hyperlipidemia and atherosclerosis (LDLr(-/-)Apob(100/100)). In agreement with previous reports, inhibition of SCD1 protected against diet-induced obesity, insulin resistance, and hepatic steatosis. Unexpectedly, however, SCD1 inhibition strongly promoted aortic atherosclerosis, which could not be reversed by dietary oleate. Further analyses revealed that SCD1 inhibition promoted accumulation of saturated fatty acids in plasma and tissues and reduced plasma triglyceride, yet had little impact on low-density lipoprotein cholesterol. Because dietary saturated fatty acids have been shown to promote inflammation through toll-like receptor 4, we examined macrophage toll-like receptor 4 function. Interestingly, SCD1 inhibition resulted in alterations in macrophage membrane lipid composition and marked hypersensitivity to toll-like receptor 4 agonists. CONCLUSIONS: This study demonstrates that atherosclerosis can occur independently of obesity and insulin resistance and argues against SCD1 inhibition as a safe therapeutic target for the metabolic syndrome.