Neutrophil-lymphocyte ratio as a link between complex pedal ulcers and poor clinical results after infrainguinal surgical revascularization.

BACKGROUND: Our aim was to evaluate the influence of preoperative neutrophil-lymphocyte ratio (NLR) on patency and clinical results after infrainguinal surgical revascularization for chronic limb ischemia. METHODS: Retrospective analysis of 150 infrainguinal autologous bypasses performed to infragenicular popliteal artery or tibial vessels in 140 (93%) patients with chronic limb-threatening ischemia (CLTI) and in 10 (7%) with disabling claudication. NLR was calculated using blood samples obtained 24 hours preoperatively. The cohort was stratified into 2 groups according to interquartile ranges of NLR: "ELEVATED-NLR" (Quartile 4 N.=37) and "LOW-NLR" (Quartile 1-2-3 N.=113). Reperfused ulcers were described using the WIfI classification. Patency, freedom from MALE and amputation-free survival at 24 months were calculated using the Kaplan-Meier method. Univariate comparisons between NLR groups were performed using the Log-Rank test. Statistical differences on univariate analysis were adjusted in a multivariate model (Cox regression). RESULTS: NLR values were similar between CLTI and claudication. Ischemic ulcers were more frequent, (83.4% vs. 59.3% P<0.01), more severe (W2-3: 37.8% vs. 22.1% P=0.01) and pedal infection was deeper (fI 2-3: 40.5% vs. 18.6% P=0.003) in "ELEVATED-NLR" group. Severe ischemia (I3) was similar between groups. High NLR values were independent predictors of patency loss (HR: 1.77 CI95% [1.01-3.10] P=0.04), MALE (HR: 2.04 CI95% [1.03-4.04] P=0.04) and worse amputation-free survival (HR:2.10 CI95% [1.06-4.14] P=0.03) rates at 24 months. CONCLUSIONS: High preoperative NLR values are associated with severe and deep infected ulcers and predicts primary patency loss, higher major adverse limb events and worse amputation-free survival rates on long-term follow-up after infrainguinal surgical revascularization.

Efecto del clopidogrel vs. aspirina en la función de la expresión del inflamasoma proaterosclerótico NLRP1 en células endoteliales. Estudio ECLOAS / Effect of clopidogrel vs. aspirin on pro-atherosclerotic NLRP1 inflammasome expression in endothelial cells. ECLOAS study

INTRODUCCIÓN Y OBJETIVOS: Se ha demostrado que el inflamasoma NLRP1 es clave en la disfunción endotelial, estando las plaquetas implicadas en las reacciones inflamatorias que la desencadenan. Investigamos la inhibición in vivo de la inflamación plaquetario-dependiente mediante inhibición del receptor P2Y vía ADP comparada con la de la enzima COX sobre la transcripción del NLRP1 en las células endoteliales. MÉTODOS: Estudio prospectivo, aleatorizado, abierto y cruzado con 2 periodos de inhibición plaquetaria en 20 voluntarios sanos, administrando clopidogrel 75mg/día/7días y aspirina 100mg/día/7días de forma cruzada tras un periodo de lavado de una semana. Las células endoteliales aórticas humanas (HAEC) fueron estimuladas 2h con plasma obtenido de los pacientes antes y después de la inhibición plaquetaria. La cuantificación de la expresión de NLRP1 se determinó mediante análisis qRT PCR. RESULTADOS: Las HAEC expuestas a plasma basal de individuos sanos presentaron niveles más elevados del NLRP1 que las expuestas a plasma de los participantes tras la administración de aspirina o clopidogrel [cuantificación relativa (CR), 1,077±0,05 vs. 1,002±0,06; OR, 1,8; IC95, 1,1-2,9; p < 0,01 y 1,077±0,05 vs. 1,04±0,03; OR, 1,7; IC95, 1,2-2,6; p < 0,001, respectivamente]. La expresión del NLRP1 en HAEC expuestas a plasma de los participantes tras la administración de aspirina o clopidogrel fue similar a las HAEC sin exposición a plasma humano (PBS) [CR 1,002±0,06 vs. 1,009±0,03; OR, 0,9; IC95, 0,5-1,4; p = 0,7 y 1,04±0,03 vs. 1,009±0,03; OR, 0,8; IC95, 0,3-1,2; p = 0,5, respectivamente]. No hubo diferencias en el porcentaje de reducción del NLRP1 en las HAEC expuestas al plasma tras la toma de aspirina comparado con la provocada por el plasma de estos mismos sujetos tras clopidogrel (3,8% vs. 2,8%, p = 0,3, respectivamente). CONCLUSIONES: La inhibición plaquetaria por vías P2Y y COX provoca similar efecto en la inhibición del inflamasoma proaterogénico NLRP1 en las HAEC

INTRODUCTION AND OBJECTIVES: NRP1 inflammasome is crucial in endothelial dysfunction. Platelets are mandatory for the inflammation that precedes it. Aspirin could inhibit NLRP1 inflammasome in endothelial cells, and clopidogrel could also provoke a reduction in vascular inflammation. A study was carried out on the influence of platelet inflammatory inhibition by P2Y receptor inhibition versus COX enzyme inhibition on the transcription of NLRP1 inflammasome in endothelial cells. METHODS: An open-label, prospective, randomised crossover study with two periods of platelet inhibition enrolled 20 healthy volunteers. They received clopidogrel 75mg/day/7days and aspirin 100mg/day/7days. A venous blood sample was collected from all participants before and after this period. Human aortic endothelial cells (HAECs) were exposed for 2h in cultures. NLRP1 gene expression was then analysed in these cultures. RESULTS: HAEC cultures that were exposed to baseline plasma showed higher expression of NLRP1 than HAECs exposed to plasma after one week of aspirin or clopidogrel intake [relative quantification (RQ), 1.077±0.05 vs. 1.002±0.06; OR, 1.8; 95% CI, 1.1-2.9; P<.01 and 1.077±0.05 vs. 1.04±0.03; OR, 1.7; 95% CI, 1.2-2.6; P<.001, respectively]. NLRP1 expression in HAEC cultures exposed to plasma after one week of aspirin or clopidogrel was similar to that observed in control HAECs that was no exposed to human plasma (PBS) [RQ; 1.002±0.06 vs. 1.009±0.03; OR, 0.9; 95% CI, 0.5-1.4; P=.7, and 1.04±0.03 vs. 1.009±0.03; OR, 0.8; 95% CI, 0.3-1.2; P=.5, respectively]. No difference was observed in NLRP1 percentage reduction in HAEC after aspirin or clopidogrel exposure (3.8% vs. 2.8%, P=.3, respectively). CONCLUSIONS: Platelet inhibition by P2Y pathway is similar to COX pathway in NLRP1 expression inhibition in HAECs

Effect of clopidogrel vs. aspirin on pro-atherosclerotic NLRP1 inflammasome expression in endothelial cells. ECLOAS study. / Efecto del clopidogrel vs. aspirina en la función de la expresión del inflamasoma proaterosclerótico NLRP1 en células endoteliales. Estudio ECLOAS.

INTRODUCTION AND OBJECTIVES: NRP1 inflammasome is crucial in endothelial dysfunction. Platelets are mandatory for the inflammation that precedes it. Aspirin could inhibit NLRP1 inflammasome in endothelial cells, and clopidogrel could also provoke a reduction in vascular inflammation. A study was carried out on the influence of platelet inflammatory inhibition by P2Y receptor inhibition versus COX enzyme inhibition on the transcription of NLRP1 inflammasome in endothelial cells. METHODS: An open-label, prospective, randomised crossover study with two periods of platelet inhibition enrolled 20 healthy volunteers. They received clopidogrel 75mg/day/7days and aspirin 100mg/day/7days. A venous blood sample was collected from all participants before and after this period. Human aortic endothelial cells (HAECs) were exposed for 2h in cultures. NLRP1 gene expression was then analysed in these cultures. RESULTS: HAEC cultures that were exposed to baseline plasma showed higher expression of NLRP1 than HAECs exposed to plasma after one week of aspirin or clopidogrel intake [relative quantification (RQ), 1.077±0.05 vs. 1.002±0.06; OR, 1.8; 95% CI, 1.1-2.9; P<.01 and 1.077±0.05 vs. 1.04±0.03; OR, 1.7; 95% CI, 1.2-2.6; P<.001, respectively]. NLRP1 expression in HAEC cultures exposed to plasma after one week of aspirin or clopidogrel was similar to that observed in control HAECs that was no exposed to human plasma (PBS) [RQ; 1.002±0.06 vs. 1.009±0.03; OR, 0.9; 95% CI, 0.5-1.4; P=.7, and 1.04±0.03 vs. 1.009±0.03; OR, 0.8; 95% CI, 0.3-1.2; P=.5, respectively]. No difference was observed in NLRP1 percentage reduction in HAEC after aspirin or clopidogrel exposure (3.8% vs. 2.8%, P=.3, respectively). CONCLUSIONS: Platelet inhibition by P2Y pathway is similar to COX pathway in NLRP1 expression inhibition in HAECs.

Aspirin-Dependent Platelet Inflammatory Inhibition in Healthy Subjects Decreases NLRP-1 Inflammasome.

BACKGROUND: Inflammation and endothelial dysfunction are implicated in the onset of atherosclerosis. Inflammasome activation takes part in the pathogenesis of the atherosclerotic disease. This study investigated the influence of platelet inflammatory inhibition on the transcription of intracitosolic nucleotide-binding oligomerization domain-like receptor protein 1 (NLRP-1) inflammasome in endothelial cells. METHODS: This experimental study enrolled 10 healthy volunteers with no cardiovascular risk factors and normal results on vascular examination. They received low doses of aspirin (100 mg/day) for seven days. A venous blood sample was collected in all subjects before aspirin intake and after the experimental week. Human aortic endothelial cell (HAEC) cultures were exposed to baseline plasma and plasma from subjects after aspirin intake. NLRP-1 gene expression was analyzed in these cultures. RESULTS: HAEC cultures that were exposed to plasma from subjects at baseline showed higher expression of NLRP-1 than HAECs exposed to plasma of healthy volunteers after one week on salicilate intake (relative quantification, 1.077 ± 0.05 vs. 1.002 ± 0.06; odds ratio, 1.8; 95 confidence interval, 1.1-2.9; P < 0.01). CONCLUSIONS: Data observed in the our study indicate that in HAECs, the intracytosolic NLRP-1 expression is attenuated by the auto/paracrine platelet inhibition by aspirin, without direct platelet-endothelial cell interaction.

Rationale and Design of Randomized Clinical Trial for the Assessment of Macitentan Efficiency as Coadjuvant Treatment to Open and Endovascular Revascularization in Critical Limb Ischemia.

INTRODUCTION: Critical limb ischemia (CLI) is defined by ischemic rest pain, tissue loss, or both, secondary to arterial insufficiency, and its prevalence is increasing mainly as a result of the worldwide high prevalence of diabetes. Currently, there are no available conclusive data on the efficacy of any coadjuvant therapy after revascularization procedure benefiting amputation and patency rates. Macitentan is an orally active dual endothelin (ET) receptor antagonist that may contribute to reduce the amputation rate and improve revascularization patency in CLI. METHODS/DESIGN: REVASC is a proposed pilot, open-label, controlled, randomized, single-center clinical double-blind trial to be conducted in Spain on a study population of European patients with CLI, which will compare the clinical outcomes and cost-effectiveness of macitentan coadjuvant treatment after limb revascularization with the standard antiplatelet treatment strategy for severe limb ischemia. Patients are randomized 1:1 to receive macitentan or placebo for 12 weeks. The primary clinical end point will be amputation-free survival rate at 12 months, defined as the time to major (above the ankle) amputation for the index (trial) limb or death from any cause, whichever comes first. Secondary outcomes include overall survival, quality of life, in-hospital mortality and morbidity, repeat interventions, healing of tissue loss, and hemodynamic changes following revascularization. Sample size is estimated as 120 patients. The economic analysis will consist of two components: a "within-study" analysis, which will be based on study end points; and a "model-based" analysis, which will extrapolate and compare costs and effects likely to accrue beyond the study follow-up period. DISCUSSION: The REVASC trial is designed to be pragmatic and represents current practice of the real-world population management after limb revascularization for CLI due to atherosclerosis. Current evidence does not support any coadjuvant treatment. A new pathway of treatment may be opened with the use of ET receptor antagonists in these patients.