bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successional dynamics of carbon sequestration in forests of the eastern United States
Authors: Canham Charles D. , Murphy Lora , Hansen Winslow D. 
Published: April 2024

AbstractCarbon sequestration in the forests of the eastern United States is an important offset to the country's CO2 emissions. Much of the eastern forestland is the product of reforestation of abandoned agricultural land or recovery following clear‐cutting over a century ago. This has led to concerns that eastern forests are even‐aged and that rates of carbon sequestration will decline as forests increase in carbon. Our objective was to examine the successional dynamics of forest carbon sequestration—using live tree carbon stocks as a proxy for successional status—for the six broadly defined forest types present in the region. We used datasets from the National Forest Inventory (NFI) for the 31 US states from Minnesota south to Louisiana and eastward and analyzed live tree net carbon increment for 2007–2021, the period for which NFI plot remeasurement data were available for all 31 states. Spruce–fir and southern pines were the only forest types for which carbon increment declined even modestly over a significant fraction of the range of live tree carbon observed in the region, and southern pine–hardwood forests were the only forests in which predicted sequestration in live tree carbon declined to zero within the range of carbon stocks observed in the region. Northern hardwood–conifer forests, oak–hickory forests, and lowland forests experienced either no decline or a slight increase in sequestration in live tree carbon across the range of successional status observed in the region. Thus, the average stocks of live tree carbon per unit area increased steadily over the study period. At some point in succession, rates of mortality are expected to increase and balance gross growth, leading to zero net sequestration in live tree carbon. Mature and old‐growth stands, however, are rare in all six forest types, and mortality as a fraction of live tree carbon for all six forest types declined across the range of successional status present in the region. Our results thus provide no support for the hypothesis that the successional dynamics of forests in this region can be expected to lead to near‐term declines in net carbon sequestration.
Using density surface models to assess the ecological effectiveness of a protected area network in Tanzania
Authors: Giliba Richard A. , Kiffner Christian , Fust Pascal , Loos Jacqueline 
Published: April 2024

AbstractGiven recent global endeavors to increase protected area coverage, it is crucial to comprehensively evaluate the efficacy of various area‐based conservation strategies in effectively reducing biodiversity loss. Here, we investigated the responses of wildlife populations to different protection levels and environmental variables at the landscape scale in the Katavi–Rukwa Ecosystem, western Tanzania. To this end, we conducted line distance sampling surveys and counted the dung of six target mammal species (elephant, giraffe, buffalo, zebra, topi, and hartebeest) along foot transects within areas differing in protection levels (from strict to less‐strictly protected: national park, game reserve, forest reserve, game‐controlled area, and unprotected areas). Based on these dung counts, we modeled the spatial distribution of these six mammal species using a species‐specific density surface modeling framework. We found consistent effects of protection level and land use variables on the spatial distribution of the target mammal species: dung densities were highest in the national park and game reserves, intermediate in less‐strictly protected areas, and lowest in unprotected areas. Beyond species‐specific environmental predictors for dung densities, our results highlight consistent negative associations between dung densities of the target species and distance to cropland and avoidance of areas in proximity to houses. Our findings underpin differences in ecological effectiveness of protected areas within one ecosystem. Protection level and land use play crucial roles in moderating the spatial distribution of all considered mammal species. Our findings suggest that a landscape approach needs to guide effective conservation across the entire protection gradient of the Katavi–Rukwa Ecosystem.
Litter accumulation suppresses grass production but facilitates shrub expansion in a long‐term fenced grassland
Authors: Zhang Yiwen , Chang Xiaofeng , Zhang Yuwei , Wilkes Andreas , Wang Guojie 
Published: April 2024

AbstractShrub expansion is increasing in grasslands worldwide and has profound effects on biodiversity and ecosystem functions. Shrub expansion has primarily been explained by extrinsic factors such as climate change and human activities, yet the roles of intrinsic shrub demographic population dynamic and shrub–grass interaction remain poorly understood. With a paired mown and exclosure comparison experiment and baseline levels of shrub abundance in a semiarid grassland, we confirmed that long‐term livestock exclusion promotes expansion of two native shrubs, Artemisia sacrorum and Caragana brachypoda. Shrub abundance increased during the livestock exclusion period. Shrub biomass in fenced plots was about 5‐ to 10‐fold greater than in mown plots. Both increase in population density and individual size (especially height) contributed to shrub increase. The mechanism behind this was the divergent effects of litter accumulation on shrubs and grasses. Litter accumulation suppressed grass production, while facilitating shrub recruitment and growth. Our findings highlight the potential role of litter accumulation‐mediated shifts in shrub–grass interactions, which should be incorporated into grazing top‐down control to better predict the restoration outcomes of grassland management changes. The identified internal biotic mechanism raises the possibility that removal of accumulated litter by grazing or mowing may be an alternative way to maintain or restore a grass‐dominated state in shrub expansion areas.
ECMO for drug‐refractory electrical storm without a reversible trigger: a retrospective multicentric observational study
Authors: Durães‐Campos Isabel , Costa Catarina , Ferreira Ana Rita , Basílio Carla , Torrella Pau , Neves Aida , Lebreiro Ana Margarida , Pestana Gonçalo , Adão Luís , Pinheiro‐Torres José , Solla‐Buceta Miguel , Riera Jordi , Chico‐Carballas Juan Ignacio , Gaião Sérgio , Paiva José Artur , Roncon‐Albuquerque Roberto 
Published: April 2024

AbstractAimsDrug‐refractory electrical storm (ES) is a life‐threatening medical emergency. We describe the use of venoarterial extracorporeal membrane oxygenation (VA‐ECMO) in drug‐refractory ES without a reversible trigger, for which specific guideline recommendations are still lacking.Methods and resultsRetrospective observational study in four Iberian centres on the indications, treatment, complications, and outcome of drug‐refractory ES not associated with acute coronary syndromes, decompensated heart failure, drug toxicity, electrolyte disturbances, endocrine emergencies, concomitant acute illness with fever, or poor compliance with anti‐arrhythmic drugs, requiring VA‐ECMO for circulatory support. Thirty‐four (6%) out of 552 patients with VA‐ECMO for cardiogenic shock were included [71% men; 57 (44–62) years], 65% underwent cardiopulmonary resuscitation before VA‐ECMO implantation, and 26% during cannulation. Left ventricular unloading during VA‐ECMO was used in 8 (24%) patients: 3 (9%) with intraaortic balloon pump, 3 (9%) with LV vent, and 2 (6%) with Impella. Thirty (88%) had structural heart disease and 8 (24%) had an implantable cardioverter‐defibrillator. The drug‐refractory ES was mostly due to monomorphic ventricular tachycardia (VT) and ventricular fibrillation (VF) (59%), isolated monomorphic VT (26%), polymorphic VT (9%), or VF (6%). Thirty‐one (91%) required deep sedation, 44% overdrive pacing, 36% catheter ablation, and 26% acute autonomic modulation. The main complications were nosocomial infection (47%), bleeding (24%), and limb ischaemia (21%). Eighteen (53%) were weaned from VA‐ECMO, and 29% had heart transplantation. Twenty‐seven (79%) survived to hospital discharge (48 (33–82) days). Non‐survivors were older [62 (58–67) vs. 54 (43–58); P < 0.01] and had a higher first rhythm disorder‐to‐ECMO interval [0 (0–2) vs. 2 (1‐11) days; P = 0.02]. Seven (20%) had rehospitalization during follow‐up [29 (12–48) months], with ES recurrence in 6%.ConclusionsVA‐ECMO bridged drug‐refractory ES without a reversible trigger with a high success rate. This required prolonged hospital stays and coordination between the ECMO centre, the electrophysiology laboratory, and the heart transplant programme.
Outcomes with T‐wave discordance of left bundle branch block and preserved or mildly reduced ejection fraction
Authors: Huang Hui‐Chun , Chien Kuo‐Liong , Liu Yen‐Bin 
Published: April 2024

AbstractAimsLeft bundle branch block (LBBB) is associated with an increased risk of adverse outcomes for patients with heart failure. The prognosis of LBBB in patients with a preserved ejection fraction (EF) remains controversial. This study investigated the predictive value of T‐wave discordance for the prognosis of patients with LBBB and preserved or mildly reduced EF.Methods and resultsWe enrolled 707 patients with complete LBBB and left ventricular (LV) EF ≥ 40% observed using electrocardiograms (ECGs) and echocardiograms between January 2010 and December 2018. Their serial ECGs were reviewed during the follow‐up period. The T‐wave pattern was classified as discordant LBBB (dLBBB) or concordant LBBB (cLBBB) according to the 12‐lead ECG T‐wave morphology. The primary outcome was the composite of cardiovascular death or hospitalization for heart failure during a median follow‐up period of 3.1 years. A multivariable Cox regression analysis was used to evaluate the independent predictors of the primary outcome. Patients with dLBBB had more comorbidities, a higher heart rate, a longer QRS and QTc duration, a larger LV end‐systolic volume and left atrial dimension, a lower LVEF, and a higher mitral E/A ratio and E/e′, compared with those with cLBBB. Older age [hazard ratio (HR) = 1.023, 95% confidence interval (CI) = 1.001–1.046, P = 0.023], history of heart failure (HR = 2.440, 95% CI = 1.524–3.905, P = 0.001), chronic kidney disease (HR = 1.917, 95% CI = 1.182–3.110, P = 0.008), larger LV end‐systolic volume (HR = 1.046, 95% CI = 1.017–1.075, P = 0.002), lower LVEF (HR = 0.916, 95% CI = 0.885–0.948, P = 0.001), and presence of dLBBB (HR = 1.63, 95% CI = 1.011–2.628, P = 0.032) were independent predictors of the primary outcome in patients with LBBB and LVEF ≥ 40%. The discordant or concordant T‐wave morphology of LBBB could transform from one subtype to the other in up to 23% of the study population during the follow‐up period, and individuals with persistent or transformed dLBBB faced an increased risk of cardiovascular death or non‐fatal heart failure hospitalization.ConclusionsIn patients with LBBB and EF ≥ 40%, dLBBB serves as an independent predictor of a higher risk of cardiovascular death or non‐fatal heart failure hospitalization.
Transition from asymptomatic to symptomatic systolic chronic heart failure: rationale and design of TransitionCHF
Authors: Sandek Anja , Edelmann Frank , Gertler Christoph , Friede Tim , Wachter Rolf , Hasenfuß Gerd ,   TransitionCHF consortium
Published: April 2024

AbstractAimsChronic systolic heart failure (CHF) is a major health burden. A relevant number of patients shows asymptomatic left ventricular dysfunction (ALVSD) before symptomatic CHF or becomes asymptomatic after initiating heart failure therapy. Clinical course, prognosis, and response to pharmacological and device‐based treatment are largely unknown in these two distinct groups of patients. Current pharmacological and interventional therapies do neither properly address the underlying pathophysiology nor prevent malignant loss of function. New therapeutic paradigms are needed to stop the progression from asymptomatic to symptomatic heart failure. Key questions are what causes progression of clinically asymptomatic New York Heart Association (NYHA) I heart failure to overt heart failure (>NYHA I) in some but not all patients and the underlying reasons for this transition. This requires the identification of disease mechanisms and biomarkers that predict outcome in well‐defined cohorts for innovative preclinical and clinical trials.Methods and resultsTransitionCHF is a prospective, multicentre, longitudinal pathophysiological evaluation cohort study in patients with asymptomatic systolic dysfunction NYHA I and left ventricular ejection fraction ≤40%. The cohort comprises both incidental findings and patients who had become asymptomatic after a previous symptomatic event. TransitionCHF has recruited 1000 patients with ALVSD caused by various aetiologies in 20 university heart failure clinics across Germany. Both patients with and without comorbidities at study entry will be recruited. Patients will be systematically investigated and followed up annually over the course of the study. The primary composite endpoint is time to hospitalization for heart failure and cardiovascular death. The secondary endpoints assess time to all‐cause mortality, to cardiovascular mortality, to heart failure mortality, to all‐cause hospitalization, to heart failure hospitalization, and to recurrent heart failure hospitalizations, as well as time to assist device implantation/transplantation. Additional investigations focusing on biomarkers, comorbidities, gender aspects, nutrition, and functional parameters including quality of life will be performed.ConclusionsTransitionCHF will provide a more thorough pathophysiological understanding of the progression of asymptomatic systolic dysfunction into symptomatic heart failure that will help develop therapies tailored to prevent progressive heart failure.
Impact of guideline‐directed medical therapy on systolic blood pressure and cardiovascular outcomes in patients with heart failure and low blood pressure: A systematic review and meta‐analysis
Authors: Li Jingwei , Chen Yunlong , Wang Yi , Liu Xiaoyan , Li Ping , He Yongming , Hao Yang , Huang Lan , Jin Jun , Wang Jiang , Anderson Craig 
Published: April 2024

AbstractAimsExisting research indicates that patients with heart failure (HF) may have restricted access to guideline‐directed medical therapy (GDMT) when their blood pressure (BP) is comparatively low. However, recent clinical trials suggest that HF patients with low BP could still benefit from certain HF medications, which have a minimal impact on BP. This systematic review and meta‐analysis was conducted to determine whether this applies to all GDMT.Methods and resultsA systematic search of MEDLINE and EMBASE was conducted for studies published from inception to 10 January 2024. Randomized controlled trials were selected if they reported on the longitudinal change of systolic BP (SBP) due to GDMT, or the risks of cardiovascular events in HF patients based on SBP categories. Weighted mean difference (WMD), hazard ratio or relative risk, and corresponding 95% confidence intervals (CI) were pooled for meta‐analysis where possible. Data from 20 studies, encompassing information on 84 782 individuals, were analysed. Overall, GDMT is associated with lower SBP (WMD, −2.16; 95% CI −2.86 to −1.46), with no significant difference between baseline low and non‐low BP subgroups (interaction p = 0.810). However, SBP of the treatment group increased by 5.8 mmHg from baseline in the low SBP subgroup during follow‐up, while it decreased by 4.0 mmHg in the baseline non‐low SBP subgroup. GDMT demonstrated similar cardiovascular benefits and risk of hypotension between low and non‐low SBP subgroups (interaction p = 0.318 and 0.903, respectively).ConclusionsGuideline‐directed medical therapy is associated with a negligible decrease in SBP, but can provide similar cardiovascular benefits in both low and non‐low SBP HF patients, with no significant interaction with SBP as to hypotension. Therefore, GDMT should be initiated and maintained in HF patients with low BP.
N‐terminal pro‐B‐type natriuretic peptide post‐discharge monitoring in the management of patients with heart failure and preserved ejection fraction – a randomized trial: The NICE study
Authors: Pascual‐Figal Domingo A. , Hernández‐Vicente Alvaro , Pastor‐Pérez Francisco , Martínez‐Sellés Manuel , Solé‐González Eduard , Alvarez‐García Jesús , García‐Pavía Pablo , Varela‐Román Alfonso , Sánchez Pedro Luis , Delgado Juan F. , Noguera‐Velasco Jose A. , Bayes‐Genis Antoni ,   NICE study investigators
Published: April 2024

AimsThere is a lack of specific studies assessing the impact of natriuretic peptide monitoring in the post‐discharge management of patients with heart failure (HF) and preserved ejection fraction (HFpEF), throughout the vulnerable phase following acute HF hospitalization. The NICE study aims to assess the clinical benefit of incorporating N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) into the post‐discharge management of HFpEF patients.Methods and resultsIndividuals admitted with HFpEF (left ventricular ejection fraction >50%) were included in a multicentre randomized controlled study employing an open‐label design with event blinding (NCT02807168). Upon discharge, 157 patients were randomly allocated to either NT‐proBNP monitoring (n = 79) or no access to NT‐proBNP (control group, n = 78) during pre‐scheduled visits at 2, 4 and 12 weeks. Clinical endpoints were evaluated at 6 months. The primary endpoint of HF rehospitalizations occurred in 12.1% patients, without significant differences observed between the NT‐proBNP monitoring group (12.8%) and the control group (11.4%) (hazard ratio [HR] 1.15, 95% confidence interval [CI] 0.47–2.81, p = 0.760). Regarding secondary endpoints, the NT‐proBNP monitoring group demonstrated a significantly lower risk of death (1.3% vs. 10.1%; HR 0.12, 95% CI 0.02–0.98; p = 0.048), whereas non‐HF hospitalizations (12.8% vs. 19.0%, p = 0.171) and any adverse clinical event (26.9% vs. 36.7%, p = 0.17) did not reach statistical significance [Correction added on 29 April 2024, after first online publication: In the preceding sentence, “95% CI 0.02 ‐ 0.09” has been corrected to “95% CI 0.02 ‐ 0.98; p = 0.048” in this version.]. Awareness of NT‐proBNP levels were associated with higher doses of diuretics and renin–angiotensin system inhibitors (angiotensin‐converting enzyme inhibitors/angiotensin II receptor blockers) in the NT‐proBNP monitoring group.ConclusionsPost‐discharge monitoring of NT‐proBNP in HFpEF patients did not exhibit an association with reduced rates of HF hospitalization in this study. Nonetheless, it appears to enhance global clinical management by optimizing medical therapies and contributing to improved overall survival.
Left atrial to coronary sinus shunting for treatment of heart failure with mildly reduced or preserved ejection fraction: The ALT FLOW Early Feasibility Study 1‐year results
Authors: Urey Marcus A. , Hibbert Benjamin , Jorde Ulrich , Eckman Peter , Simard Trevor , Labinaz Marino , Nazer Babak , Wiley Mark , Gupta Bhanu , Sauer Andrew , Shah Hirak , Sorajja Paul , Pineda Andres M. , Missov Emil , Mahmud Ehtisham , Kahwash Rami , Lilly Scott , Latib Azeem , Murthy Sandhya , Fam Neil , Garcia Santiago , Chung Eugene S. , Klein Liviu , Cheng Richard , Houston Brian A. , Amoroso Nicholas S. , Chang Lee , Gafoor Sameer , Chaudhry Sunit‐Preet , Hermiller James , Schwartz Jonathan G. , Aldaia Lillian , Koulogiannis Konstantinos , Gray William A. , Zahr Firas 
Published: April 2024

AbstractAimsPatients with heart failure and mildly reduced or preserved ejection fraction have limited therapeutic options. The ALT‐FLOW Early Feasibility Study evaluated safety, haemodynamics and outcomes for the APTURE transcatheter shunt system, a novel left atrium to coronary sinus shunt in these patients.Methods and resultsSafety and shunt implantation success was evaluated for all 116 enrolled patients. An analysis population of implanted patients with a left ventricular ejection fraction (LVEF) >40% (n = 95) was chosen to assess efficacy via paired comparison between baseline and follow‐up haemodynamic (3 and 6 months), and echocardiographic, clinical and functional outcomes (6 months and 1 year). Health status and quality of life outcomes were assessed using the Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ‐OSS). The primary safety endpoint, major adverse cardiac, cerebral, and renal events, and reintervention through 30 days, occurred in 3/116 patients (2.6%). All implanted shunts were patent at 1 year. In patients with LVEF >40%, the mean (95% confidence interval) reduction in exercise pulmonary capillary wedge pressure (PCWP) at 20 W was −5.7 (−8.6, −2.9) mmHg at 6 months (p < 0.001). At baseline, 8% had New York Heart Association class I–II status and improved to 68% at 1 year (p < 0.001). KCCQ‐OSS at baseline was 39 (35, 43) and improved at 6 months and 1 year by 25 (20–30) and 27 (22–32) points, respectively (both p < 0.0001). No adverse changes in haemodynamic and echocardiographic indices of right heart function were observed at 1 year. Overall, the reduction in PCWP at 20 W and improvement in KCCQ‐OSS in multiple subgroups were consistent with those observed for the entire population.ConclusionsIn patients with heart failure and LVEF >40%, the APTURE shunt demonstrated an acceptable safety profile with significant sustained improvements in haemodynamic and patient‐centred outcomes, underscoring the need for further evaluation of the APTURE shunt in a randomized trial.
Vagal tone, pain sensitivity and exercise‐induced hypoalgesia: The effect of physical activity level
Authors: Michaeli Izak Ela , Kodesh Einat , Weissman‐Fogel Irit 
Published: April 2024

AbstractBackgroundVagal activity has analgesic effects that are attributed to exercise‐induced hypoalgesia (EIH). High vagal tone and low pain sensitivity are reported in individuals who routinely exercise yet, their association is unclear. Furthermore, it is unknown if the heightened vagal tone following high physical activity predicts and intensifies EIH.MethodsFifty‐one healthy participants (27 low–moderately physically active; 27 females) underwent a resting‐state electrocardiogram followed by heart rate variability analysis. Pain measurements, including pressure (PPT) and heat (HPT) pain thresholds, ratings of tonic heat pain (THP) and conditioned pain modulation (CPM) paradigm, were conducted pre‐ and post‐exercise on a cycle ergometer.ResultsThe highly active group demonstrated higher vagal tone compared to the low–moderately active (root mean square of successive differences between R–R intervals: 63.96.92 vs. 34.78 ms, p = 0.018; percentage of successive R–R intervals that exceed 50 ms: 24.41 vs. 11.52%, p = 0.012). Based on repeated‐measure ANOVA, the highly active group showed higher PPT at pre‐exercise, compared to the low–moderately active group (382 kPa vs. 327 kPa; p = 0.007). Post‐exercise, both groups demonstrated EIH, increased HPT (p = 0.013) and decreased THP ratings (p < 0.001). Linear regression revealed that only in the low–moderately active group, higher vagal tone was associated with more efficient pre‐exercise CPM and a greater reduction in THP ratings post‐exercise (p ≤ 0.01).ConclusionsHighly active individuals demonstrate greater vagal tone and lower pain sensitivity but no greater EIH. Vagal tone moderates pain inhibition efficiency and EIH only in low–moderately active individuals. These findings suggest that physical activity level moderates the vagal–pain association via the endogenous analgesia system.SignificanceHighly physically active individuals exhibit greater vagal tone and reduced sensitivity to experimental pain, yet they do not benefit more from exercise‐induced hypoalgesia (EIH) compared to low–moderately active individuals. Moreover, low–moderately active individuals with greater vagal tone exhibited more efficient endogenous pain inhibition and greater EIH, suggestive of the moderation effect of physical activity level on vagal–pain associations.