E-Cigarettes induce expression of procoagulant tissue factor in cultivated human endothelial cells.

BACKGROUND: E-cigarettes (ECIG) are proposed as an alternative for regular tobacco users with less dangerous effects for health. Several studies demonstrated that ECIG exert deleterious cardiovascular effects and promote platelet dependent thrombosis. However, ECIG role on Tissue Factor-dependent thrombosis is still unknown. Dysfunctional endothelial cells (ECs) are known to express Tissue Factor (TF) on their surface. Aim of the present study was to investigate whether ECIG might promote TF expression in ECs, shifting them to a pro thrombotic phenotype. METHODS: Human Umbilical Vein Endothelial Cells (HUVEC) were incubated with increasing doses of ECIG (commercially available and mix of propylene glycol/vegetable glycerine/nicotine 18 mg/mL) up to 1.8 mg/mL. TF gene expression and protein levels were assessed at different time points by Real Time PCR and Western Blot, respectively. TF surface expression and activity were also measured by FACS analysis and coagulation assay. Finally, NF-kB translocation was investigated as possible mechanism of action. Potential protective effects by Rosuvastatin were also investigated. RESULTS: ECIG significantly increased TF expression at both gene and protein levels in a time and dose dependent manner. Surface expression and procoagulant activity were increased as well. These phenomena appeared modulated by the NF-κB pathway. Rosuvastatin reduced ECIG effects on TF-mRNA. CONCLUSIONS: Although in vitro, we indicate that ECIG promote a pro thrombotic phenotype in ECs via expression of functional TF. Data of the present study permit to shed a brighter light on the still partially unresolved issue about the role of ECIG in development of cardiovascular diseases suggesting that they might represent a potential risk factor for thrombotic cardiovascular events.

Acute Hyperglycemia-Induced Injury in Myocardial Infarction.

Acute hyperglycemia is a transient increase in plasma glucose level (PGL) frequently observed in patients with ST-elevation myocardial infarction (STEMI). The aim of this review is to clarify the molecular mechanisms whereby acute hyperglycemia impacts coronary flow and myocardial perfusion in patients with acute myocardial infarction (AMI) and to discuss the consequent clinical and prognostic implications. We conducted a comprehensive literature review on the molecular causes of myocardial damage driven by acute hyperglycemia in the context of AMI. The negative impact of high PGL on admission recognizes a multifactorial etiology involving endothelial function, oxidative stress, production of leukocyte adhesion molecules, platelet aggregation, and activation of the coagulation cascade. The current evidence suggests that all these pathophysiological mechanisms compromise myocardial perfusion as a whole and not only in the culprit coronary artery. Acute hyperglycemia on admission, regardless of whether or not in the context of a diabetes mellitus history, could be, thus, identified as a predictor of worse myocardial reperfusion and poorer prognosis in patients with AMI. In order to reduce hyperglycemia-related complications, it seems rational to pursue in these patients an adequate and quick control of PGL, despite the best pharmacological treatment for acute hyperglycemia still remaining a matter of debate.

Periprocedural myocardial infarction in patients undergoing complex versus noncomplex percutaneous coronary intervention.

BACKGROUND: Limited data are available on the risk of periprocedural myocardial infarction (MI) in patients undergoing complex versus noncomplex percutaneous coronary intervention (PCI). METHODS: We assessed the risk of periprocedural MI according to the fourth Universal definition of myocardial infarction (UDMI) and several other criteria among patients undergoing elective PCI in a prospective, single-center registry. Complex PCI included at least one of the following: 3 coronary vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation with 2 stents implanted, total stent length >60 mm, treatment of chronic total occlusion, and use of rotational atherectomy. RESULTS: Between 2017 and 2021, we included 1010 patients with chronic coronary syndrome, of whom 226 underwent complex PCI (22.4%). The rate of periprocedural MI according to the fourth UDMI was significantly higher in complex compared to noncomplex PCI patients (26.5% vs. 14.5%, p < 0.001). Additionally, periprocedural MI was higher in the complex PCI group using SCAI (4% vs. 1.1%, p = 0.009), ARC-2 (13.7% vs. 8.0%, p = 0.013), ISCHEMIA (5.8% vs. 1.7%, p = 0.002), and EXCEL criteria (4.9% vs. 2.0%, p = 0.032). SYNTAX periprocedural MI occurred at low rates in both groups (0.9% vs. 0.6%, p = 0.657). Complex PCI was an independent predictor of the fourth UDMI periprocedural MI (odds ratio [OR] 1.54, 95% confidence interval [CI]: 1.04-2.27, p = 0.031). CONCLUSIONS: In patients with chronic coronary syndrome undergoing elective PCI, complex PCI is associated with a significantly higher risk of periprocedural MI using multiple definitions. These findings highlight the importance of considering upfront this risk in the planning of complex PCI procedures.

Platelet Inhibition with Ticagrelor 60 mg Versus 90 mg Twice Daily in Elderly Patients with Acute Coronary Syndrome: Rationale and Design of the PLINY THE ELDER Trial.

BACKGROUND: Elderly status is steadily increasing among patients with acute coronary syndrome (ACS). Dual antiplatelet therapy (DAPT) with aspirin and a potent P2Y12 receptor inhibitor is the cornerstone of treatment to prevent recurrent thrombotic complications in patients with ACS. However, DAPT in older patients is challenged by a concurrent heightened risk of ischemia and bleeding. The aim of this study is to evaluate the pharmacodynamic and pharmacokinetic profile of a lower dose of ticagrelor (60 mg twice daily) among elderly patients during the early phase of ACS. STUDY DESIGN: PLINY THE ELDER (PLatelet INhibition with two different doses of potent P2y12 inhibitors in THE ELDERly population) (NCT04739384) is a prospective, randomized, open-label, crossover trial to evaluate the non-inferiority of a lower dose of ticagrelor (60 mg twice daily) compared with a standard dose (90 mg twice daily) among elderly patients with ACS undergoing percutaneous coronary intervention (PCI). A total of 50 patients, aged 75 years or more, with indication to potent P2Y12 receptor inhibitors will be randomized within 3 days from PCI for the index ACS. Patients with indication to oral anticoagulant therapy, treatment with glycoprotein IIb/IIIa inhibitors, or active bleeding will be excluded. The primary endpoint is platelet reactivity determined by P2Y12 reaction units (PRU) (VerifyNow, Accumetrics, San Diego, CA, USA) after treatment with ticagrelor 60 or 90 mg twice daily for 14 days. Secondary endpoints will include other pharmacodynamic tests of ADP-induced aggregation (light transmittance aggregometry and multiple electrode aggregometry) and determination of pharmacokinetic profile (plasma levels of ticagrelor and its metabolite AR-C124910XX) by high performance liquid chromatography-tandem mass spectrometry. CONCLUSIONS: The PLINY THE ELDER trial will determine whether a lower dose of ticagrelor confers non-inferior platelet inhibition compared with the standard dose in the early phase of ACS among elderly patients undergoing PCI, informing future clinical investigation.

Colchicine in Athero-Thrombosis: Molecular Mechanisms and Clinical Evidence.

Several lines of evidence have clearly indicated that inflammation plays a pivotal role in the development of atherosclerosis and of its thrombotic complications such as acute coronary syndromes or ischemic stroke. Thus, it has been postulated that the use of anti-inflammatory agents might be extremely useful to improve cardiovascular outcome. Recently, increasing attention has been reserved to one of the oldest plant-derived drugs still in use in clinical practice, colchicine that has been used as drug to treat inflammatory diseases such gout or Mediterranean fever. To date, current guidelines of the European Society of Cardiology have included colchicine as first line choice for treatment of acute and recurrent pericarditis. Moreover, several studies have investigated its role in the clinical scenarios of cardiovascular disease including chronic and acute coronary syndromes with promising results. In this review, starting from a description of the mechanism(s) involved behind its anti-inflammatory effects, we give an overview on its potential effects in atherothrombosis and finally present an updated overview of clinical evidence on the role of this drug in cardiovascular disease.

Effects of colchicine on tissue factor in oxLDL-activated T-lymphocytes.

Several studies have shown that T-cells might be involved in pathophysiology of acute coronary syndromes (ACS). Tissue factor (TF) plays a key role in ACS. Many evidences have indicated that some statins reduce TF expression in several cell types. However, literature about rosuvastatin and TF and about statins effects on T-cells is still scanty. Colchicine is an anti-inflammatory drug recently proven to have beneficial effects in ACS via unknown mechanisms. This study investigates the effects of colchicine and rosuvastatin on TF expression in oxLDL-activated T-cells. T-cells, isolated from buffy coats of healthy volunteers, were stimulated with oxLDL (50 µg/dL). T-cells were pre-incubated with colchicine (10 µM) or rosuvastatin (5 µM) for 1 h and then stimulated with oxLDL (50 µg/mL). TF gene (RT-PCR), protein (western blot), surface expression (FACS) and procoagulant activity (FXa generation assay) were measured. NF-κB/IκB axis was examined by western blot analysis and translocation assay. Colchicine and rosuvastatin significantly reduced TF gene, and protein expression and procoagulant activity in oxLDL stimulated T-cells. This effect was associated with a significant reduction in TF surface expression as well as its procoagulant activity. These phenomena appear modulated by drug effects on the transcription factor NF-kB. Rosuvastatin and colchicine prevent TF expression in oxLDL-stimulated T-cells by modulating the NF-κB/IκB axis. Thus, we speculate that this might be another mechanism by which these drugs exert benefic cardiovascular effects.

Cangrelor, Tirofiban, and Chewed or Standard Prasugrel Regimens in Patients With ST-Segment-Elevation Myocardial Infarction: Primary Results of the FABOLUS-FASTER Trial.

BACKGROUND: Standard administration of newer oral P2Y12 inhibitors, including prasugrel or ticagrelor, provides suboptimal early inhibition of platelet aggregation (IPA) in patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention. We aimed to investigate the effects of cangrelor, tirofiban, and prasugrel, administered as chewed or integral loading dose, on IPA in patients undergoing primary percutaneous coronary intervention. METHODS: The FABOLUS-FASTER trial (Facilitation Through Aggrastat or Cangrelor Bolus and Infusion Over Prasugrel: A Multicenter Randomized Open-Label Trial in Patients with ST-Elevation Myocardial Infarction Referred for Primary Percutaneous Intervention) is an investigator-initiated, multicenter, open-label, randomized study. A total of 122 P2Y12-naive patients with ST-segment-elevation myocardial infarction were randomly allocated (1:1:1) to cangrelor (n=40), tirofiban (n=40) (both administered as bolus and 2-hour infusion followed by 60 mg of prasugrel), or 60-mg loading dose of prasugrel (n=42). The latter group underwent an immediate 1:1 subrandomization to chewed (n=21) or integral (n=21) tablets administration. The trial was powered to test 3 hypotheses (noninferiority of cangrelor compared with tirofiban using a noninferiority margin of 9%, superiority of both tirofiban and cangrelor compared with chewed prasugrel, and superiority of chewed prasugrel as compared with integral prasugrel, each with α=0.016 for the primary end point, which was 30-minute IPA at light transmittance aggregometry in response to 20 µmol/L adenosine diphosphate. RESULTS: At 30 minutes, cangrelor did not satisfy noninferiority compared with tirofiban, which yielded superior IPA over cangrelor (95.0±8.9 versus 34.1±22.5; P<0.001). Cangrelor or tirofiban were both superior to chewed prasugrel (IPA, 10.5±11.0; P<0.001 for both comparisons), which did not provide higher IPA over integral prasugrel (6.3±11.4; P=0.47), despite yielding higher prasugrel active metabolite concentration (ng/mL; 62.3±82.6 versus 17.1±43.5; P=0.016). CONCLUSIONS: Cangrelor provided inferior IPA compared with tirofiban; both treatments yielded greater IPA compared with chewed prasugrel, which led to higher active metabolite concentration but not greater IPA compared with integral prasugrel. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02978040; URL: https://www.clinicaltrialsregister.eu; EudraCT 2017-001065-24.

Anorexia nervosa-related cardiopathy in children with physical instability: prevalence, echocardiographic characteristics and reversibility at mid-term follow-up.

Prompt detection of cardiovascular abnormalities in children with anorexia nervosa and physical instability requiring hospitalization is essential to identify patients at higher cardiovascular risk. We studied all anorexia nervosa children requiring admission at Paediatric Institute in the period 2015-2019. Anorexia nervosa cardiopathy at admission was defined by the presence of at least two of the following clinical findings: pericardial effusion, mitral regurgitation, bradycardia, mitral billowing, aortic regurgitation, altered LV morphology and ECG abnormalities. Echocardiographic data were compared with those registered at 3-8-month follow-up and with data from a healthy population. Thirty-eight anorexia nervosa children were examined. Prevalence of anorexia nervosa cardiopathy at admission was 63% (24 patients). Pericardial effusion, bradycardia and mitral regurgitation were present together in 26% of patients. Most cardiovascular changes recovered at follow-up. Anorexia nervosa cardiopathy was associated with significantly lower left ventricle end-diastolic diameters and mass, and higher E wave, E/A and E/e' ratios and left ventricle sphericity index values vs healthy population and vs anorexia nervosa children without cardiopathy (p<0.05). Left ventricle global longitudinal strain was significantly reduced only in anorexia nervosa cardiopathy patients but recovered, whereas end-diastolic diameters, E/A ratio and sphericity index values remained impaired.Conclusion: Among anorexia nervosa children requiring hospitalization, those presenting several cardiac findings together express an acute anorexia nervosa cardiopathy which is characterized by worse LV filling, geometry and subclinical myocardial deformation impairment. Despite treatment, in those patients, some alterations persist at mid-term follow-up. What is Known: • Cardiac and electrocardiographic changes are present in anorexia nervosa children at diagnosis or during stable disease, and most recover after body-weight treatment. • It is unknown if anorexia nervosa children with more severe cardiac impairment during hospitalization present higher cardiovascular-risk profile despite treatment. What is New: • In anorexia nervosa children needing hospitalization for physical reasons, prevalence of acute anorexia nervosa cardiopathy at admission is high, around 60%. • By advanced echocardiography, children with anorexia nervosa cardiopathy at admission have a worse cardiac filling, impaired cardiac geometry and systolic deformation that only partially recover at mid-term follow-up.

Low-Dose Ticagrelor in Patients With High Ischemic Risk and Previous Myocardial Infarction: A Multicenter Prospective Real-World Observational Study.

Prolonged dual antiplatelet therapy after 12 months in patients with previous myocardial infarction (MI) is attractive to reduce long-term ischemic complications. In the PEGASUS-TIMI 54, the use of low-dose ticagrelor (60 mg b.i.d.) plus aspirin after 12 months from MI reduced the risk of ischemic events, at the price of limited increase on bleeding complications. However, data on the use of low-dose ticagrelor in real-world practice lack. We aim at providing data on prescription/eligibility criteria and outcomes in patients receiving low-dose ticagrelor in the real-world setting. We enrolled consecutive patients eligible for ticagrelor 60 mg according to Italian national regulation in 3 high-volume centers and collected 1-year outcomes. The primary objective of the study is to generate real-world data about clinical characteristics, eligibility criteria, major adverse cardiovascular events, bleeding, and adverse event in patients receiving low-dose ticagrelor from our cohort. One hundred eighty-one patients were consecutively enrolled with a median follow-up of 18 months. The most used and the least used prescription criteria were multivessel coronary disease (72.4%) and chronic kidney disease (15.5%), respectively. At 1-year follow-up, the rate of major adverse cardiovascular events was 4.97%; of these, 3.86% of patients had a MI, and 1.1% had a stroke/transient ischemic attack, whereas no major bleeding occurred. In conclusion, in a real-world study, including patients with previous MI, low-dose ticagrelor for prolonged dual antiplatelet therapy showed to be effective and safe, with no major bleeding occurring at follow-up.

Effects of colchicine on platelet aggregation in patients on dual antiplatelet therapy with aspirin and clopidogrel.

Platelets aggregation leading to thrombosis plays a pivotal role in the pathophysiology of acute coronary syndrome (ACS) and of stent thrombosis. Antiplatelet therapy with aspirin plus an ADP-receptor inhibitor (ticagrerol, prasugrel or clopidogrel) is recommended to reduce the risk of other platelet-mediated events. Clopidogrel is recommended in patients with Chronic Coronary Syndromes (CCS) or in ACS patients at high bleeding risk. Unfortunately, up to 30% of patients are non-responders to clopidogrel and show residual high platelet reactivity (HPR). Colchicine (COLC) is a drug with cardiovascular effects. We have demonstrated that COLC might exert protective cardiovascular effects by interfering with cytoskeleton rearrangement, a phenomenon involved in platelet aggregation. Here, we investigate in vitro the effects of colchicine on platelet aggregation of patients on DAPT with clopidogrel. Platelets obtained from 35 CCS patients on therapy with clopidogrel were pre-incubated with COLC 10 µM before being stimulated with ADP (20 µM), or TRAP (25 µM) at 0, 30, 60 and 90 min to measure max aggregation by LTA. Platelets not COLC-preincubated served as controls. Seven patients were pre-selected as clopidogrel non-responders. COLC significantly reduced TRAP-induced platelet aggregation in clopidogrel responders and non-responders. Interestingly, COLC inhibited ADP-induced platelet aggregation in clopidogrel non-responders in which ADP still caused activation despite DAPT. We demonstrate that COLC inhibits platelet aggregation in clopidogrel non-responders with HPR despite DAPT with this ADP receptor-inhibitor. Further in vivo studies should be designed to evaluate the opportunity to prescribe colchicine after ACS/CCS to overcome the clopidogrel limitations in the DAPT therapy.

A rare case of deep vein and right atrial thrombosis in a patient with chronic heart failure and pulmonary embolism.

Deep vein thrombosis (DVT) is frequently observed in patients with chronic heart failure (CHF), increasing the risk of pulmonary embolism (PE). Clinical evaluation of CHF patients with suspected acute PE is challenging since these diseases share several symptoms and signs such as dyspnea. Thus, it is intuitive that correct and fast diagnosis of PE in these patients might be able to significantly change their clinical outcome. In the present report, we describe a rare case of a patient with CHF and PE due to a huge thrombosis of deep veins and of right atrium in whom echo evaluation permitted the correct diagnosis and therapy.

Self-expandable sirolimus-eluting stents compared to second-generation drug-eluting stents for the treatment of the left main: A propensity score analysis from the SPARTA and the FAILS-2 registries.

OBJECTIVES: To compare the effectiveness and safety of self-expandable, sirolimus-eluting Stentys stents (SES) and second-generation drug-eluting stents (DES-II) for the treatment of the unprotected left main (ULM). BACKGROUND: SES may provide a valuable option to treat distal ULM, particularly when significant caliber gaps with side branches are observed. METHODS: Patients from the multicenter SPARTA (clinicaltrials.gov: NCT02784405) and FAILS2 registries were included. Propensity-score with matching was performed to account for the lack of randomization. Primary end-point was the rate of major adverse cardiovascular events (MACE, a composite of all cause death, myocardial infarction, target lesion revascularization [TLR], unstable angina and definite stent thrombosis [ST]). Single components of MACE were the secondary end-points. RESULTS: Overall, 151 patients treated with SES and 1270 with DES-II were included; no differences in MACE rate at 250 days were observed (9.8% vs. 11.5%, P = 0.54). After propensity score with matching, 129 patients treated with SES and 258 with DES-II, of which about a third of female gender, were compared. After a follow-up of 250 days, MACE rate did not differ between the two groups (9.9% vs. 8.5%, P = 0.66), as well as the rate of ULM TLR (1.6% vs. 3.1%, P = 0.36) and definite ST (0.8% vs. 1.2%, P = 0.78). These results were consistent also when controlling for the treatment with provisional vs. 2-stents strategies for the ULM bifurcation. CONCLUSION: SES use for ULM treatment was associated with a similar MACE rate compared to DES-II at an intermediate-term follow-up. SES might represent a potential option in this setting.

Lights and shadows of long-term dual antiplatelet therapy in "real life" clinical scenarios.

Dual antiplatelet therapy (DAPT) is a cornerstone of treatment for patients with acute coronary syndromes (ACS). Mounting evidences have opened the debate about the optimal DAPT duration. Considering the ACS-pathophysiology, the most recent guidelines recommend DAPT in all ACS patients for at least 12 months unless there are contraindications such as excessive risk of bleeding. Thus, it can be considered acceptable earlier discontinuation if the risk of morbidity from bleeding outweighs the anticipated benefit. On the other hand, several studies have clearly indicated that a significant burden of platelet related-events, such as stroke and new ACS might occur after this period, suggesting that potential benefits might derive by prolonging DAPT beyond 12 months (Long DAPT). Indeed, although current guidelines give some indications about patients eligible for Long DAPT, they do not embrace several real-life clinical scenarios. Thus, in such scenarios, how to decide whether a patient is eligible for Long DAPT or not might be still challenging for clinicians. This position paper presents and discusses various "real-life" clinical scenarios in ACS patients, in order to propose several possible recommendations to overcome guidelines potential limitations.

The left atrial appendage: from embryology to prevention of thromboembolism.

The left atrial appendage (LAA) is the main source of thromboembolism in patients with non-valvular atrial fibrillation (AF). As such, the LAA can be the target of specific occluding device therapies. Optimal management of patients with AF includes a comprehensive knowledge of the many aspects related to LAA structure and thrombosis. Here we provide baseline notions on the anatomy and function of the LAA, and then focus on current imaging tools for the identification of anatomical varieties. We also describe pathogenetic mechanisms of LAA thrombosis in AF patients, and examine the available evidence on treatment strategies for LAA thrombosis, including the use of non-vitamin K antagonist oral anticoagulants and interventional approaches.

Moderate-intensity statin therapy seems ineffective in primary cardiovascular prevention in patients with type 2 diabetes complicated by nephropathy. A multicenter prospective 8 years follow up study.

BACKGROUND: Although numerous studies and metanalysis have shown the beneficial effect of statin therapy in CVD secondary prevention, there is still controversy such the use of statins for primary CVD prevention in patients with DM. The purpose of this study was to evaluate the occurrence of total major adverse cardio-vascular events (MACE) in a cohort of patients with type 2 diabetes complicated by nephropathy treated with statins, in order to verify real life effect of statin on CVD primary prevention. METHODS: We conducted an observational prospective multicenter study on 564 patients with type 2 diabetic nephropathy free of cardiovascular disease attending 21 national outpatient diabetes clinics and followed them up for 8 years. 169 of them were treated with statins (group A) while 395 were not on statins (group B). RESULTS: Notably, none of the patients was treated with a high-intensity statin therapy according to last ADA position statement. Total MACE occurred in 32 patients from group A and in 68 patients from group B. Fatal MACE occurred in 13 patients from group A and in 30 from group B; nonfatal MACE occurred in 19 patients from group A and in 38 patients from group B. The analysis of the Kaplan-Meier survival curves showed a not statistically significant difference in the incidence of total (p 0.758), fatal (p 0.474) and nonfatal (p 0.812) MACE between the two groups. HbA1c only showed a significant difference in the incidence of MACE between the two groups (HR 1.201, CI 1.041-1.387, p 0.012). CONCLUSIONS: These findings suggest that, in a real clinical setting, moderate-intensity statin treatment is ineffective in cardiovascular primary prevention for patients with diabetic nephropathy. Trial registration ClinicalTrials.gov Identifier NCT00535925. Date of registration: September 24, 2007, retrospectively registered.

Pregnancy-associated plasma protein-A promotes TF procoagulant activity in human endothelial cells by Akt-NF-κB axis.

Pregnancy-associated plasma protein-A (PAPP-A) is a metalloproteinase with a controversial role in pathophysiology of cardiovascular disease. It seems involved in progression of atherosclerosis and is widely represented in atherosclerotic plaque. PAPP-A plasma levels are elevated in patients with acute coronary syndromes (ACS), thus it has been suggested that it might be a prognostic marker for developing major cardiovascular events. However, the pathophysiological link(s) between PAPP-A and ACS are still unknown. Several studies have indicated that tissue factor (TF) plays a pivotal role in the pathophysiology of ACS by triggering the formation of intracoronary thrombi following endothelial injury. This study investigates whether PAPP-A, at concentrations measurable in ACS patients, might induce TF expression in human endothelial cells in culture (HUVEC). In HUVEC, PAPP-A induced TF-mRNA transcription as demonstrated by real time PCR and expression of functionally active TF as demonstrated by FACS analysis and pro-coagulant activity assay. PAPP-A induced TF expression through the activation of Akt/NF-κB axis, as demonstrated by luciferase assay and by suppression of TF-mRNA transcription as well as of TF expression/activity by Akt and NF-κB inhibitors. These data indicate that PAPP-A promotes TF expression in human endothelial cells and support the hypothesis that this proteinase, besides being involved in progression of atherosclerosis, does not represent an independent risk factor for adverse cardiovascular events, but it rather might play an "active" role in the pathophysiology of ACS as an effector molecule able to induce a pro-thrombotic phenotype in endothelial cells.

Reactive oxygen species induce a procoagulant state in endothelial cells by inhibiting tissue factor pathway inhibitor.

Tissue factor pathway inhibitor (TFPI) is a serine-protease inhibitor, which modulates coagulation tissue factor-dependent (TF). It binds directly and inhibits the TF-FVII/FVIIa complex as well as FXa. Time to reperfusion of acute ischemic myocardium is essential for tissue salvage. However, reperfusion also results in a unique form of myocardial damage, such as contractile dysfunction, decreased coronary flow and altered vascular reactivity. Oxidants and reactive oxygen species (ROS) formation is increased in the post-ischemic heart and is responsible of post-ischemic injury. It has been reported that ROS promote a procoagulant state via TF expression while no data are available on the effect on TFPI. Endothelial cells were incubated with two different ROS generating systems, xanthine (X)/xanthine oxidase (XO) for 5 min, or H2O2 (500 µM) for 24 h. TFPI activity was measured in supernatants by chromogenic assay and TFPI-mRNA analyzed by RT-PCR 2 h after ROS exposure. Unstimulated cells and cells exposed to either X or XO served as controls. Western blot and ligand dot blot was performed to evaluate ROS effect on TFPI structure and binding to FXa. ROS generated by X/XO as well as H2O2 system resulted in decreased TFPI activity compared to unstimulated cells while X or XO alone had no effect. No differences in TFPI mRNA levels versus controls was observed. A significant degradation of TFPI was induced by ROS exposure, resulting in a decreased ability to bind FXa. ROS induce a procoagulant state in endothelial cells by altering TFPI structure, resulting in inhibition of TFPI binding to Factor Xa and loss of activity. This phenomenon might have important consequences during reperfusion of post-ischemic myocardium.

Fructose induces prothrombotic phenotype in human endothelial cells : A new role for "added sugar" in cardio-metabolic risk.

Intake of large amounts of added sweeteners has been associated with the pathogenesis of cardiometabolic risk. Several studies have shown that fructose increases the cardiovascular risk by modulating endothelial dysfunction and promoting atherosclerosis. Recently, a potential role for fructose in cardiovascular thrombosis has been suggested but with controversial results. Tissue factor (TF) plays a pivotal role in the pathophysiology of cardiovascular thrombosis by triggering the formation of intracoronary thrombi following endothelial injury. This study investigates the effects of fructose, in a concentration range usually observed in the plasma of patients with increased cardiovascular risk, on TF in human umbilical endothelial cells (HUVECs). Cells were stimulated with increasing concentrations of fructose (0.25, 1 and 2.5 mM) and then processed to evaluate TF-mRNA levels by real-time PCR as well as TF expression/activity by FACS analysis and procoagulant activity. Finally, a potential molecular pathway involved in modulating this phenomenon was investigated. We demonstrate that fructose induces transcription of mRNA for TF. In addition, we show that this monosaccharide promotes surface expression of TF that is functionally active. Fructose effects on TF appear modulated by the oxygen free radicals through activation of the transcription factor NF-κB since superoxide dismutase and NF-κB inhibitors suppressed TF expression. Data of the present study, although in vitro, indicate that fructose, besides promoting atherosclerosis, induces a prothrombotic phenotype in HUVECs, thus indicating one the mechanism(s) by which this sweetener might increase cardiometabolic risk.

ß1-adrenergic receptor and sphingosine-1-phosphate receptor 1 (S1PR1) reciprocal downregulation influences cardiac hypertrophic response and progression to heart failure: protective role of S1PR1 cardiac gene therapy.

BACKGROUND: The sphingosine-1-phosphate receptor 1 (S1PR1) and ß1-adrenergic receptor (ß1AR) are G-protein-coupled receptors expressed in the heart. These 2 receptors have opposing actions on adenylyl cyclase because of differential G-protein coupling. Importantly, both of these receptors can be regulated by the actions of G-protein-coupled receptor kinase-2, which triggers desensitization and downregulation processes. Although classic signaling paradigms suggest that simultaneous activation of ß1ARs and S1PR1s in a myocyte would simply result in opposing action on cAMP production, in this report we have uncovered a direct interaction between these 2 receptors, with regulatory involvement of G-protein-coupled receptor kinase-2. METHODS AND RESULTS: In HEK (human embryonic kidney) 293 cells overexpressing both ß1AR and S1PR1, we demonstrated that ß1AR downregulation can occur after stimulation with sphingosine-1-phosphate (an S1PR1 agonist), whereas S1PR1 downregulation can be triggered by isoproterenol (a ß-adrenergic receptor agonist) treatment. This cross talk between these 2 distinct G-protein-coupled receptors appears to have physiological significance, because they interact and show reciprocal regulation in mouse hearts undergoing chronic ß-adrenergic receptor stimulation and in a rat model of postischemic heart failure. CONCLUSIONS: We demonstrate that restoration of cardiac plasma membrane levels of S1PR1 produces beneficial effects that counterbalance the deleterious ß1AR overstimulation in heart failure.

Low platelet count at admission has an adverse impact on outcome in patients with acute coronary syndromes: from the START Antiplatelet registry.

Some previous observations suggest that a low platelet count is associated with an increased risk of adverse outcomes in patients with acute coronary syndromes (ACS). However, most of the data come from post-hoc analyses of randomized controlled trials and from studies including thrombocytopenia developed during hospital stay. Our aim was to assess the impact of low platelet count at admission on cardiovascular outcomes and treatment approach in patients hospitalized for ACS in a current real-life setting in Italy. Patients admitted to Italian coronary care units for ACS were enrolled in the START-ANTIPLATELET registry. Baseline clinical characteristics and treatment at discharge were recorded. Patients were followed-up at 6 months, 1 year and yearly thereafter. Low platelet count was defined as a count at admission < 150 > 100 k/µl or < 100 k/µL. Among 1894 enrolled patients, 157 (8.3%) had a platelet count < 150 > 100 k/µl and 30 (1.6%) < 100 k/µl. The median follow-up was 12.3 months (0.4-50.1). patients with low platelets were older (72 ± 10.4 vs 66 ± 12.4 years, p = 0.006), more frequently males (82.9 vs 72.1%, p = 0.001), hypertensive (90.0% vs 70.4%, p = 0.03), with non-valvular atrial fibrillation (NVAF) (17.1 vs 8.6%, p = 0.02), and peripheral arterial disease (11.5 vs 6.2% p = 0.01) and/or had a previous myocardial infarction (40 vs 18.7%, p = 0.008) and/or a PCI (14.6 vs 7.8%, p = 0.001) than patients with normal platelets. A slightly, but significantly, lower percentage of thrombocytopenic patients were treated with primary PCI (78.1 vs 84.4%, p = 0.04) and they were more frequently discharged on aspirin plus clopidogrel rather than aspirin plus newer P2Y12 antagonists (51.9 vs 65.4%, p = 0.01). MACE-free survival was significantly shorter in thrombocytopenic patients compared to patients with normal platelets (< 150 > 100 k/µl: 37.6 vs 41.8 months, p = 0.002; HR = 2.7, 95% CIs 1.4-5.2; < 100 k/µl: 31.7 vs 41.8 months, p = 0.01; HR = 6.5, 95% CIs 1.5-29.1). At multivariate analysis, low platelet count, age at enrollment, low glomerular filtration rate, low ejection fraction, a previous ischemic stroke and NVAF were independent predictors of MACE. A low platelet count at admission identifies a subgroup of ACS patients with a significantly increased risk of MACE and these patients should be managed with special care to prevent excess adverse outcomes.