073 Right Ventricle Contractile Reserve as a Pre-operative Tool for Assessing RV failure after Continuous Flow LVAD Implantation

IntroductionLatest generation continuous flow left ventricular assist devices (LVADs) have been proposed as an alternative to heart transplantation for end-stage heart failure. However, postoperative right ventricle (RV) dysfunction remains common and has a negative impact on prognosis. Purpose of our study was to identify echocardiographic or hemodynamic parameters that could predict early RV failure after LVAD implantation in patients with biventricular dysfunction.MethodsFourteen patients with biventricular dysfunction who have been evaluated for LVAD implantation were included. Right and left ventricular dysfunction were respectively defined as: tricuspid annular plane excursion < 16 mm (TAPSE) and LV ejection fraction < 35%. In all patients, preoperative measurements were obtained at rest. In 7 patients, right heart catheterization was performed simultaneously with increasing doses of dobutamine (15γ/Kg/min). Primary endpoint was death caused by right ventricle systolic dysfunction or need for right ventricle mechanical support within 30 days after surgery (RVSD+).ResultsMean recipient age was 58±7 years. Primary end-point (RVSD+) was noted in five patients. Preoperative demographic, echocardiographic and hemodynamic data were similar between RVSD+ and RVSD- patients (Table). Percent increase of TAPSE and systolic PAP between basal and high dobutamine dose was significantly lower in RVSD+ than in RVSD- patients.ConclusionPercent increase of TAPSE and systolic PAP induced by high dose dobutamine infusion might be two interesting criteria to assess RV contractile reserve and predict RV outcome after LVAD implantation in patient with biventricular dysfunction.Baseline Measurement (n=14)Change after Dobutamine infusion,% (n=7)RVSD-RVSD+pRVSD-RVSD+pN95TAPSE, mm14±214±20.955±526±20.03Systolic PAP, mmHg51±753±60.842±84±70.05Cardiac Output, l/min3.3±0.53.5±0.50.987±1093±470.7Pulm Vasc Res, Wood3.9±14.3±10.62±41-36±70.

STE20 kinase TAOK3 regulates type 2 immunity and metabolism in obesity

Healthy adipose tissue (AT) contains ST2(+) Tregs, ILC2s, and alternatively activated macrophages that are lost in mice or humans on high caloric diet. Understanding how this form of type 2 immunity is regulated could improve treatment of obesity. The STE20 kinase Thousand And One amino acid Kinase-3 (TAOK3) has been linked to obesity in mice and humans, but its precise function is unknown. We found that ST2(+) Tregs are upregulated in visceral epididymal white AT (eWAT) of Taok3(-/-) mice, dependent on IL-33 and the kinase activity of TAOK3. Upon high fat diet feeding, metabolic dysfunction was attenuated in Taok3(-/-) mice. ST2(+) Tregs disappeared from eWAT in obese wild-type mice, but this was not the case in Taok3(-/-) mice. Mechanistically, AT Taok3(-/-) Tregs were intrinsically more responsive to IL-33, through higher expression of ST2, and expressed more PPAR & gamma; and type 2 cytokines. Thus, TAOK3 inhibits adipose tissue Tregs and regulates immunometabolism under excessive caloric intake. Maes et al. reveal an unexpected role of TAOK3 in regulating ST2(+) regulatory T cells in mouse adipose tissue. Absence of TAOK3 sustains Tregs in obesity and improves metabolic dysfunction

Déterminants cardio-vasculaires et pulmonaires de la capacité fonctionnelle chez les patients porteurs d'une sténose mitrale rhumatismale (étude prospective à propos de 28 cas)

Le traitement du rétrécissement mitral (RM) est peu bénéfique sur la capacité aérobie (VO2), sans qu'on en connaisse l'origine. 28 patients ont été examinés avant (n=10), ou après (n=18) traitement d un RM. Il a été mesuré la VO2, la diffusion pulmonaire (DLCO, volume capillaire ; VCap), et la vitesse de l onde S à l anneau tricuspide (Svd) en échocardiographie d effort. En analyse uni variée, les déterminants de la VO2 sont le sexe (p=0,001, r=0,6), la DLCO (p=0,0001, r=0,7), le VCap (p=0,013, r=0,69), le débit cardiaque (p=0,034, r=0,52), la Svd d effort (p=0,008, r=0,56). En analyse multi variée, les déterminants de la VO2 sont le VCap (p=0,013, r=0,46), et la Svd d effort (p=0,005, r=0,55). La limitation de la VO2 dans le RM est causée par une dysfonction systolique du ventricule droit et par une maladie micro vasculaire pulmonaire dont le suivi apparaît aussi important que celui de la surface mitrale.NANTES-BU Médecine pharmacie (441092101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Prevalence of sleep-disordered breathing in a 316-patient French cohort of stable congestive heart failure.

International audienceBACKGROUND: Heart failure with systolic dysfunction occurs frequently. Studies in North America and Germany have shown a high prevalence of sleep-disordered breathing in patients with heart failure. AIMS: To assess the prevalence of sleep-disordered breathing and its associated risk factors in French patients with heart failure. METHODS: A total of 316patients with stable heart failure and a left ventricular ejection fraction less or equal to 45% underwent polygraphy prospectively to diagnose sleep apnoea syndrome, defined as an apnoea-hypopnoea index greater or equal to 10events/h. RESULTS: Mean age, left ventricular ejection fraction, and body mass index were 59+/-13years, 30+/-11% and 28+/-6kg/m(2), respectively. The prevalence of sleep breathing disorder was 81% (n=256); 30% of syndromes were classified as central and 70% as obstructive. The mean apnoea-hypopnoea index was high (30+/-3events/h) and a large proportion (41%) of syndromes had an apnoea-hypopnoea index greater or equal to 30events/h. A central sleep apnoea syndrome pattern was associated with more severe heart failure and a more elevated apnoea-hypopnoea index than an obstructive pattern. The prevalence of sleep-disordered breathing was lower in women than in men (64% versus 85%; chi(2)=0.0003) as was its severity (mean apnoea-hypopnoea index 15+/-13events/h versus 27+/-19events/h, p=0.0001). CONCLUSION: The prevalence of sleep-disordered breathing was high in a French heart failure population, with most syndromes having an obstructive pattern. Prevalence and severity were higher in men than in women

Comparison of four right ventricular systolic echocardiographic parameters to predict adverse outcomes in chronic heart failure.: RV function prognostic importance in CHF.

International audienceAIMS: Heart failure (HF) has a poor prognosis. Several right ventricular (RV) echocardiographic parameters have been proposed as sensitive markers to detect patients at risk. Our objective was to compare the predictive value of four RV systolic echocardiographic parameters for outcomes in patients with HF. METHODS AND RESULTS: One hundred and thirty-six patients with stable HF and a left ventricular ejection fraction <35% were assessed for the following: (i) RV fractional area (RVFA), (ii) tricuspid annular plane systolic excursion (TAPSE), (iii) integral of the systolic wave (ISW(tdi)), and (iv) peak systolic velocity (PSV(tdi)). ISW(tdi) and PSV(tdi) were measured using tissue Doppler imaging at the tricuspid annulus. The primary endpoint was death, urgent transplantation, urgent ventricular assist device implantation, or an acute HF episode. During a mean follow-up of 295 days, 33 patients reached the primary endpoint. The cut-off thresholds for RVFA, TAPSE, PSV(tdi), and ISW(tdi) defined using receiver-operating characteristic curves were 36.8%, 13.5 mm, 9.5 cm s(-1), and 1.75 cm, respectively. On Cox multivariate analysis, NYHA, log BNP, and only PSV(tdi) from the RV systolic parameters were found to be independent predictors of outcome. CONCLUSION: PSV(tdi) is a strong independent predictor of outcome in HF at a threshold value of 9.5 cm s(-1) and appears to be superior to other RV systolic echocardiographic parameters

Grain carbon isotope composition is a marker for allocation and harvest index in wheat

The natural C-13 abundance (delta C-13) in plant leaves has been used for decades with great success in agronomy to monitor water-use efficiency and select modern cultivars adapted to dry conditions. However, in wheat, it is also important to find genotypes with high carbon allocation to spikes and grains, and thus with a high harvest index (HI) and/or low carbon losses via respiration. Finding isotope-based markers of carbon partitioning to grains would be extremely useful since isotope analyses are inexpensive and can be performed routinely at high throughput. Here, we took the advantage of a set of field trials made of more than 600 plots with several wheat cultivars and measured agronomic parameters as well as delta C-13 values in leaves and grains. We find a linear relationship between the apparent isotope discrimination between leaves and grain (denoted as Delta delta(corr)), and the respiration use efficiency-to-HI ratio. It means that overall, efficient carbon allocation to grains is associated with a small isotopic difference between leaves and grains. This effect is explained by postphotosynthetic isotope fractionations, and we show that this can be modelled by equations describing the carbon isotope composition in grains along the wheat growth cycle. Our results show that C-13 natural abundance in grains could be useful to find genotypes with better carbon allocation properties and assist current wheat breeding technologies

Grain carbon isotope composition is a marker for allocation and harvest index in wheat

International audienceThe natural C-13 abundance (delta C-13) in plant leaves has been used for decades with great success in agronomy to monitor water-use efficiency and select modern cultivars adapted to dry conditions. However, in wheat, it is also important to find genotypes with high carbon allocation to spikes and grains, and thus with a high harvest index (HI) and/or low carbon losses via respiration. Finding isotope-based markers of carbon partitioning to grains would be extremely useful since isotope analyses are inexpensive and can be performed routinely at high throughput. Here, we took the advantage of a set of field trials made of more than 600 plots with several wheat cultivars and measured agronomic parameters as well as delta C-13 values in leaves and grains. We find a linear relationship between the apparent isotope discrimination between leaves and grain (denoted as Delta delta(corr)), and the respiration use efficiency-to-HI ratio. It means that overall, efficient carbon allocation to grains is associated with a small isotopic difference between leaves and grains. This effect is explained by postphotosynthetic isotope fractionations, and we show that this can be modelled by equations describing the carbon isotope composition in grains along the wheat growth cycle. Our results show that C-13 natural abundance in grains could be useful to find genotypes with better carbon allocation properties and assist current wheat breeding technologies

Projet SYSTEM-ECO4 : Évaluation de systèmes de grandes cultures à faible usage de pesticides

National audience19 prototypes de systèmes de culture ont été testés sur quatre sites contrastés (Picardie, Bourgogne et deux sites dans la région de Toulouse). Ces systèmes de grandes cultures ont été conçus selon les principes de Protection Intégrée pour limiter l’usage des pesticides en général et des herbicides en particulier. Les combinaisons de leviers alternatifs ont permis de gérer durablement la flore adventice avec peu d’herbicides, et de baisser l’usage de l’ensemble des pesticides. Certains systèmes permettent de concilier faible IFT et bonne performance économique. Trois sites ont été instrumentés pour collecter des eaux de drainage et mesurer les transferts de substances actives. Ces dispositifs ont permis d’établir un lien entre les IFT cumulés et les quantités de substance transférées dans les eaux, à l’échelle d’un site et sur trois années de mesure, confirmant ainsi le lien entre l’usage de pesticides et leur impact. Les prototypes fondés sur le semis direct ont été décevants: ils ont nécessité beaucoup d’herbicides pour maîtriser les adventices, les quantités de substances actives transférées sous ces parcelles ont été importantes, et les performances économiques ont été moyennes