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Patients with peripheral artery disease (PAD) requiring lower extremity revascularization (LER) are at high risk of adverse limb and cardiovascular events. VOYAGER PAD demonstrated that rivaroxaban significantly reduced this risk with an overall favorable net benefit in patients undergoing surgical revascularization; however, the efficacy and safety in those treated by surgical bypass including stratified by bypass conduit (venous or prosthetic) has not been described.In the VOYAGER PAD trial, patients with PAD after surgical and endovascular infrainguinal LER were randomized to rivaroxaban 2.5 mg twice daily or placebo and followed for a median of 28 months. The primary endpoint was a composite of acute limb ischemia (ALI), major amputation of vascular etiology, myocardial infarction, ischemic stroke, or cardiovascular death. The principal safety outcome was Thrombolysis in Myocardial Infarction (TIMI) major bleeding. Index procedure details including conduit type (venous or prosthetic) were collected at baseline.Among 6564 randomized, 2185 (33%) underwent surgical LER. Of these, surgical bypass was performed in 1448 (66%), using prosthetic conduit in 773 (53%) and venous in 646 (45%). Adjusting for baseline differences and anatomic factors, the risk for unplanned limb revascularization in the placebo arm was 2.5-fold higher for those receiving prosthetic versus venous conduits (adjHR 2.53, 95% CI 1.65-3.90; p0.001) while the risk for ALI was 3 times greater (adjHR 3.07, 95% CI 1.84-5.11; p0.001). Rivaroxaban reduced the primary outcome in patients treated with bypass surgery (HR 0.78, 95% CI 0.62-0.98) with consistent benefits in those receiving venous (HR 0.66, 95% CI 0.49-0.96) and prosthetic (HR 0.87, 95% CI 0.66-1.15) conduits (pSurgical bypass with prosthetic conduit is associated with significantly higher rates of major adverse limb events relative to venous conduits even after adjusting for patient and anatomic characteristics. Adding rivaroxaban 2.5 mg twice daily to aspirin or dual antiplatelet therapy significantly reduces this risk, increases bleeding, but has a favorable benefit risk in patients treated with bypass surgery and regardless of conduit type. Rivaroxaban should be considered after lower extremity bypass for symptomatic PAD to reduce ischemic complications of the heart, limb, and brain.

Background: The VOYAGER PAD trial (Vascular Outcomes Study of ASA Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for Peripheral Artery Disease) demonstrated superiority of rivaroxaban plus aspirin versus aspirin to reduce major cardiac and ischemic limb events after lower extremity revascularization. Clopidogrel is commonly used as a short-term adjunct to aspirin after endovascular revascularization. Whether clopidogrel modifies the efficacy and safety of rivaroxaban has not been described. Methods: VOYAGER PAD was a phase 3, international, double-blind, placebo-controlled trial in patients with symptomatic PAD undergoing lower extremity revascularization randomized to rivaroxaban 2.5 mg twice daily plus 100 mg aspirin daily or rivaroxaban placebo plus aspirin. The primary efficacy outcome was a composite of acute limb ischemia, major amputation of a vascular cause, myocardial infarction, ischemic stroke, or cardiovascular death. The principal safety end point was TIMI (Thrombolysis in Myocardial Infarction) major bleeding, with International Society on Thrombosis and Haemostasis major bleeding a secondary safety outcome. Clopidogrel use was allowed at the discretion of the investigator for up to 6 months after the qualifying revascularization. Results: Of the randomized patients, 3313 (50.6%) received clopidogrel for a median duration of 29.0 days. Over 3 years, the hazard ratio for the primary outcome of rivaroxaban versus placebo was 0.85 (95% CI, 0.71–1.01) with clopidogrel and 0.86 (95% CI, 0.73–1.01) without clopidogrel without statistical heterogeneity ( P for interaction=0.92). Rivaroxaban resulted in an early apparent reduction in acute limb ischemia within 30 days (hazard ratio, 0.45 [95% CI, 0.14–1.46] with clopidogrel; hazard ratio, 0.48 [95% CI, 0.22–1.01] without clopidogrel; P for interaction=0.93). Compared with aspirin, rivaroxaban increased TIMI major bleeding similarly regardless of clopidogrel use ( P for interaction=0.71). With clopidogrel use >30 days, rivaroxaban was associated with more International Society on Thrombosis and Haemostasis major bleeding within 365 days (hazard ratio, 3.20 [95% CI, 1.44–7.13]) compared with shorter durations of clopidogrel ( P for trend=0.06). Conclusions: In the VOYAGER PAD trial, rivaroxaban plus aspirin reduced the risk of adverse cardiovascular and limb events with an early benefit for acute limb ischemia regardless of clopidogrel use. The safety of rivaroxaban was consistent regardless of clopidogrel use but with a trend for more International Society on Thrombosis and Haemostasis major bleeding with clopidogrel use >30 days than with a shorter duration. These data support the addition of rivaroxaban to aspirin after lower extremity revascularization regardless of concomitant clopidogrel, with a short course (≤30 days) associated with less bleeding. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02504216.

Background Patients with peripheral artery disease who have undergone lower-extremity revascularization are at high risk for major adverse limb and cardiovascular events. The efficacy and ...

Background: Patients with peripheral artery disease requiring lower extremity revascularization (LER) are at high risk of adverse limb and cardiovascular events. The VOYAGER PAD trial (Vascular Outcomes Study of ASA [Acetylsalicylic Acid] Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for PAD) demonstrated that rivaroxaban significantly reduced this risk. The efficacy and safety of rivaroxaban has not been described in patients who underwent surgical LER. Methods: The VOYAGER PAD trial randomized patients with peripheral artery disease after surgical and endovascular LER to rivaroxaban 2.5 mg twice daily plus aspirin or matching placebo plus aspirin and followed for a median of 28 months. The primary end point was a composite of acute limb ischemia, major vascular amputation, myocardial infarction, ischemic stroke, or cardiovascular death. The principal safety outcome was Thrombolysis in Myocardial Infarction major bleeding. International Society on Thrombosis and Haemostasis bleeding was a secondary safety outcome. All efficacy and safety outcomes were adjudicated by a blinded independent committee. Results: Of the 6564 randomized, 2185 (33%) underwent surgical LER and 4379 (67%) endovascular. Compared with placebo, rivaroxaban reduced the primary end point consistently regardless of LER method ( P -interaction, 0.43). After surgical LER, the primary efficacy outcome occurred in 199 (18.4%) patients in the rivaroxaban group and 242 (22.0%) patients in the placebo group with a cumulative incidence at 3 years of 19.7% and 23.9%, respectively (hazard ratio, 0.81 [95% CI, 0.67–0.98]; P =0.026). In the overall trial, Thrombolysis in Myocardial Infarction major bleeding and International Society on Thrombosis and Haemostasis major bleeding were increased with rivaroxaban. There was no heterogeneity for Thrombolysis in Myocardial Infarction major bleeding ( P -interaction, 0.17) or International Society on Thrombosis and Haemostasis major bleeding ( P -interaction, 0.73) on the basis of the LER approach. After surgical LER, the principal safety outcome occurred in 11 (1.0%) patients in the rivaroxaban group and 13 (1.2%) patients in the placebo group; 3-year cumulative incidence was 1.3% and 1.4%, respectively (hazard ratio, 0.88 [95% CI, 0.39–1.95]; P =0.75) Among surgical patients, the composite of fatal bleeding or intracranial hemorrhage ( P =0.95) and postprocedural bleeding requiring intervention ( P =0.93) was not significantly increased. Conclusions: The efficacy of rivaroxaban is associated with a benefit in patients who underwent surgical LER. Although bleeding was increased with rivaroxaban plus aspirin, the incidence was low, with no significant increase in fatal bleeding, intracranial hemorrhage, or postprocedural bleeds requiring intervention. Registration: URL: http://www.clinicaltrials.gov ; Unique Identifier: NCT02504216.

Chloromethane (CH3Cl) is the most abundant long-lived chlorinated organic compound in the atmosphere and contributes significantly to natural stratospheric ozone depletion. Salt marsh ecosystems including halophyte plants are a known source of atmospheric CH3Cl but estimates of their total global source strength are highly uncertain and knowledge of the major production and consumption processes in the atmosphere-halophyte-soil system is yet incomplete. In this study we investigated the halophyte plant, Salicornia europaea, and soil samples from a coastal salt marsh site in Sardinia/Italy for their potential to emit and consume CH3Cl and using flux measurements, stable isotope techniques and Arrhenius plots differentiated between biotic and abiotic processes. Our laboratory approach clearly shows that at least 6 different production and consumption processes are active in controlling atmospheric CH3Cl fluxes of a salt marsh ecosystem. CH3Cl release by dried plant and soil material was substantially higher than that from the fresh material at temperatures ranging from 20 to 70 °C. Results of Arrhenius plots helped to distinguish between biotic and abiotic formation processes in plants and soils. Biotic CH3Cl consumption rates were highest at 30 °C for plants and 50 °C for soils, and microbial uptake was higher in soils with higher organic matter content. Stable isotope techniques helped to distinguish between formation and degradation processes and also provided a deeper insight into potential methyl moiety donor compounds, such as S-adenosyl-l-methionine, S-methylmethionine and pectin, that might be involved in the abiotic and biotic CH3Cl production processes. Our results clearly indicate that cycling of CH3Cl in salt marsh ecosystems is a result of several biotic and abiotic processes occurring simultaneously in the atmosphere-plant-soil system. Important precursor compounds for biotic and abiotic CH3Cl formation might be methionine derivatives and pectin. All formation and degradation processes are temperature dependent and thus environmental changes might affect the strength of each source and sink within salt marsh ecosystems and thus considerably alter total fluxes of CH3Cl from salt marsh ecosystems to the atmosphere.

German Science Foundation (DFG KE 884/10-1 ; ANR-14-CE35-0005-01) ; French National Research Agency (DFG KE 884/10-1 ; ANR-14-CE35-0005-01); International audience; Chloromethane (CH3Cl, methyl chloride) is the most abundant volatile halocarbon in the atmosphere and involved in stratospheric ozone depletion. The global CH3Cl budget, and especially the CH3Cl sink from microbial degradation in soil, still involves large uncertainties. These may potentially be resolved by a combination of stable isotope analysis and bacterial diversity studies. We determined the stable isotope fractionation of CH3Cl hydrogen and carbon and investigated bacterial diversity during CH3Cl degradation in three soils with different properties (forest, grassland, and agricultural soils) and at different temperatures and headspace mixing ratios of CH3Cl. The extent of chloromethane degradation decreased in the order forest > grassland > agricultural soil. Rates ranged from 0.7 to 2.5 μg g−1 dry wt. d−1 for forest soil, from 0.1 to 0.9 μg g−1 dry wt. d−1 for grassland soil, and from 0.1 to 0.4 μg g−1 dry wt. d−1 for agricultural soil and increased with increasing temperature and CH3Cl supplementation. The measured mean stable hydrogen enrichment factor of CH3Cl of −50 ± 13‰ was unaffected by temperature, mixing ratio, or soil type. In contrast, the stable carbon enrichment factor depended on CH3Cl degradation rates and ranged from −38 to −11‰. Bacterial community composition correlated with soil properties was independent from CH3Cl degradation or isotope enrichment. Nevertheless, increased abundance after CH3Cl incubation was observed in 21 bacterial operational taxonomical units (OTUs at the 97% 16S RNA sequence identity level). This suggests that some of these bacterial taxa, although not previously associated with CH3Cl degradation, may play a role in the microbial CH3Cl sink in soil.

Chloromethane (CH3Cl), currently the most abundant chlorinated organic compound in the atmosphere at around ~ 550 parts per trillion by volume (pptv), is considered responsible for approximately 16% of halogen-catalyzed stratospheric ozone destruction. Although emissions of CH3Cl are known to occur from animals such as cattle, formation and release of CH3Cl from humans has not yet been reported. In this study a pre-concentration unit coupled with a gas chromatograph directly linked to a mass spectrometer was used to precisely measure concentrations of CH3Cl at the pptv level in exhaled breath from 31 human subjects with ages ranging from 3 to 87 years. We provide analytical evidence that all subjects exhaled CH3Cl in the range of 2.5 to 33 parts per billion by volume, levels which significantly exceed those of inhaled air by a factor of up to 60. If the mean of these emissions was typical for the world's population, then the global source of atmospheric CH3Cl from humans would be around 0.66 Gg yr− 1 (0.33 to 1.48 Gg yr− 1), which is less than 0.03% of the total annual global atmospheric source strength. The observed endogenous formation of a chlorinated methyl group in humans might be of interest to biochemists and medical scientists as CH3Cl is also known to be a potent methylating agent and thus, could be an important target compound in future medical research diagnostic programs.