Porphyromonas gingivalis Participates in Pathogenesis of Human Abdominal Aortic Aneurysm by Neutrophil Activation. Proof of Concept in Rats

International audienceBACKGROUND: Abdominal Aortic Aneurysms (AAAs) represent a particular form of atherothrombosis where neutrophil proteolytic activity plays a major role. We postulated that neutrophil recruitment and activation participating in AAA growth may originate in part from repeated episodes of periodontal bacteremia. METHODS AND FINDINGS: Our results show that neutrophil activation in human AAA was associated with Neutrophil Extracellular Trap (NET) formation in the IntraLuminal Thrombus, leading to the release of cell-free DNA. Human AAA samples were shown to contain bacterial DNA with high frequency (11/16), and in particular that of Porphyromonas gingivalis (Pg), the most prevalent pathogen involved in chronic periodontitis, a common form of periodontal disease. Both DNA reflecting the presence of NETs and antibodies to Pg were found to be increased in plasma of patients with AAA. Using a rat model of AAA, we demonstrated that repeated injection of Pg fostered aneurysm development, associated with pathological characteristics similar to those observed in humans, such as the persistence of a neutrophil-rich luminal thrombus, not observed in saline-injected rats in which a healing process was observed. CONCLUSIONS: Thus, the control of periodontal disease may represent a therapeutic target to limit human AAA progression

Remodelage vasculaire associé à une augmentation chronique du flux sanguin

PARIS7-Bibliothèque centrale (751132105) / SudocSudocFranceF

Prolonged mechanical ventilation after lung transplantation: risks factors and consequences on recipient outcome

BackgroundRisk factors and the incidence of prolonged mechanical ventilation (PMV) after lung transplantation (LT) have been poorly described. The study assessed predictive factors of PMV after LT.MethodsThis observational, retrospective, monocentric study included all patients who received LT in Bichat Claude Bernard Hospital between January 2016 and December 2020. PMV was defined as a duration of MV > 14 days. Independent risk factors for PMV were studied using multivariate analysis. One-year survival depending on PMV was studied using Kaplan Meier and log-rank tests. A p value <0.05 was defined as significant.Results224 LT recipients were analysed. 64 (28%) of them received PMV for a median duration of 34 [26–52] days versus 2 [1–3] days without PMV. Independent risk factors for PMV were higher body mass index (BMI) (p = 0.031), diabetes mellitus of the recipient (p = 0.039), ECMO support during surgery (p = 0.029) and intraoperative transfusion >5 red blood cell units (p < 0.001). Increased mortality rates were observed at one-year in recipients who received PMV (44% versus 15%, p < 0.001).ConclusionPMV was associated with increased morbidity and mortality one-year after LT. Preoperative risk factors (BMI and diabetes mellitus) must be considered when selecting and conditioning the recipients

Prevention of retrograde ascending aortic dissection by cardiac pacing during hybrid surgery for zone 0 aortic arch repair

International audienceBackground: Retrograde type A dissection (RTAD) after zone 0 hybrid aortic arch repair is highly lethal and not infrequent complication. The aim of this study was to assess the safety and effectiveness of rapid cardiac pacing as an adjunctive tool to prevent RTAD during or after hybrid procedures for zone 0 disease.Methods: We performed a retrospective review of 42 consecutive patients with zone 0 hybrid aortic arch repair between November 2004 and January 2018. Right ventricular pacing was carried out through unipolar electrodes attached to the epicardium of the right ventricle through the sternotomy (the indifferent electrode was in the subcutaneous tissue). Pacing was utilised during the clamping of the ascending aorta, release of the aortic clamp, and stent-graft deployment.Results: Operative indications were aortic arch aneurysm 45% (n = 19), aortic arch dissection 45% (n = 19), traumatic rupture of isthmus 7% (n = 3), and type IA endoleak 2% (n = 1). Urgent procedures 48% (n = 20). The mean proximal aortic diameter was 34.14 ± 2.9 mm. Mean stent-graft oversizing was 12.97 ± 3.4%. The 30-day mortality rate was 14% (n = 6). RTAD was observed in 7% (n = 3). The actuarial survival rate was 74% over a mean follow-up of 50 ± 30.2 months. Since January 2013, rapid right ventricular pacing (overdrive pacing at a rate of 200 beats/min) was systematically used (n = 24). No RTAD was observed in this group of patients. Rapid right ventricular pacing reduced significatively the risk of RTAD (P = 0.038).Conclusions: Rapid right ventricular pacing is an effective method of inducing hypotension and appears to decrease the risk of retrograde type A dissection after zone 0 hybrid aortic arch repair

Determinants of the survival benefit of lung transplantation in patients with chronic obstructive pulmonary disease.

International audienceRATIONALE: Although chronic obstructive pulmonary disease is the first indication for lung transplantation, the benefit of the procedure in terms of survival remains debated. OBJECTIVES: To estimate the determinants of the survival benefit of lung transplantation in patients with chronic obstructive pulmonary disease. METHODS: Using information from the United Network for Organ Sharing database on 8,182 patients, we developed an approach based on numerical simulations to estimate the survival effect of lung transplantation. MEASUREMENTS AND MAIN RESULTS: The main outcome measure was the difference between median survival with transplantation and that without transplantation measured from time of transplant list registration. Survival benefit was greater with double than with single lung transplantation (mean difference, 307 d [95% confidence interval, 217-523]). With double lung transplantation, 44.6% of patients would gain 1 year or more, 29.4% would gain or lose less than 1 year, and 26% would lose 1 year or more. Major determinants of the survival effect of transplantation were systolic pulmonary artery pressure, FEV(1), body mass index, exercise capacity, functional status, and the need for continuous mechanical ventilation or oxygen. For instance, 79% of patients with an FEV(1) less than 16% of the predicted value would gain 1 year or more with double lung transplantation as compared with only 11% of patients with an FEV(1) of more than 25%. CONCLUSIONS: We identified several factors associated with the survival benefit of lung transplantation. External validation of our models is required before translating these results into clinical practice

Esmolol Corrects Severe Hypoxemia in Patients with Femoro-Femoral Venoarterial Extracorporeal Life Support for Lung Transplantation

Competitive flows syndrome result in severe regional hypoxemia when the deoxygenated flow from the native left ventricle (LV) competes with oxygenated flow from extracorporeal life support (ECLS) pump with potentially severe consequences for the cerebral and coronary circulations. Fast correction of hypoxemia could be obtained by decreasing native LV flow by infusion of a short-acting beta-blocker (esmolol). Our purpose was to retrospectively review the efficacy of esmolol in this situation and hypothesize on the potential mechanisms of action and the associated risks. This is a retrospective analysis of five clinical cases, who underwent lung transplantation and a femoro-femoral venoarterial (VA) ECLS. The patients presented severe hypoxemia (SpO2 < 85%) measured through photoplethysmography on a right hand finger. From the patients' medical records and anesthesia flowcharts, hemodynamic, right heart catheterization, echocardiography variables, and arterial blood gas results were noted before and after injection of esmolol. Mechanical ventilation and VA ECLS function variables were optimized and unchanged before and after esmolol injection. All patients had terminal respiratory failure with pulmonary hypertension and conserved LV systolic function. Immediately following esmolol injection (1.3 ± .7 mg/kg; mean ± 1 SD), SpO2 increased from 73% ± 12 to 95% ± 6; blood to arterial partial pressure in CO2 (PaCO2) decreased from 52 ± 18 to 35 ± 7 mmHg systolic pulmonary artery pressure decreased from 61 ± 8 to 50 ± 12 mmHg; the pulmonary artery oxygen saturation (SvO2); increased from 51% ± 24 to 77% ± 12; systemic arterial pressure or catecholamine requirements were unchanged. In conclusion, these results suggest that injection of esmolol allowed rapid correction of regional hypoxemia occurring during lung transplantation despite femoro-femoral VA ECLS. The mechanism is probably a decreased cardiac output of the native LV due to esmolol-induced negative inotropic and chronotropic effects without significant adverse effects on systemic tissue perfusion