Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
1.
Ecol Appl ; 33(2): e2775, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36344448

RESUMO

The frequency and intensity of forest disturbances, such as drought and fire, are increasing globally, with an increased likelihood of multiple disturbance events occurring in short succession. Disturbances layered over one another may influence the likelihood or intensity of subsequent events (a linked disturbance) or impact response and recovery trajectories (a compound disturbance), with substantial implications for ecological spatiotemporal vulnerability. This study evaluates evidence for disturbance interactions of drought followed by wildfire in a resprouting eucalypt-dominated forest (the Northern Jarrah Forest) in southwestern Australia. Sites were stratified by drought (high, low), from previous modeling and ground validation, and fire severity (high, moderate, unburnt), via remote sensing using the relative difference normalized burn ratio (RdNBR). Evidence of a linked disturbance was assessed via fine fuel consumption and fire severity. Compound disturbance effects were quantified at stand scale (canopy height, quadratic mean diameter, stem density) and stem scale (mortality). There was no evidence of prior drought influencing fine fuel consumption or fire severity and, hence, no evidence of a linked disturbance. However, compound disturbance effects were evident; stands previously affected by drought experienced smaller shifts in canopy height, quadratic mean diameter, and stem density than stands without prior drought impact. At the stem scale, size and fire severity were the strongest determinants of stem survival. Proportional resprouting height was greater in high drought sites than in low drought sites (p < 0.01), meaning, structurally, the low drought stands decreased in height more than the high drought stands. Thus, a legacy of the drought was evident after the wildfire. Although these resprouting eucalypt forests have been regarded as particularly resilient, this study illustrates how multiple disturbances can overwhelm the larger tree component and promote an abundance of smaller stems. We suggest that this is early evidence of a structural destabilization of these forests under a more fire-prone, hotter, and drier future climate.


Assuntos
Incêndios , Incêndios Florestais , Secas , Florestas , Árvores/química
2.
Heart Lung Circ ; 29(8): 1112-1121, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31831263

RESUMO

BACKGROUND: The East Timor Hearts Fund (ETHF) is a charitable organisation of Australian cardiologists providing outreach screening in Timor-Leste. For patients requiring intervention, ETHF arranges logistics, procedures, and postoperative care. The aim of this project is to evaluate outcomes of patients requiring intervention. METHODS: The ETHF database of all patients was utilised to identify patients with disease warranting surgical or percutaneous intervention. Both patients who underwent intervention and those who did not proceed to intervention were included in this study. Patients who had intervention arranged by other organisations but have then had follow-up with ETHF were also included. Overall demographics and pre and postoperative factors were assessed, with sub-group analysis of adult and paediatric patients to identify any differences in care. RESULTS: Of 221 patients requiring intervention, 101 patients underwent intervention, receiving 22 different operations or procedures. Patients were predominantly young (median age 17.5 years) and female (64.7%), with rheumatic heart disease (63.8%). Twenty-four (24) (33.3%) women aged 15-45 years old with cardiac disease warranting intervention were documented as pregnant or breastfeeding at time of clinic assessment. Of patients who did not proceed to intervention, adults were more likely to be lost to follow-up (42.4% vs 18.5%) while paediatric patients were more likely to experience progression of disease (18.5% vs 7.5%, p=0.005). Median waitlist time was 5 months, with no significant difference between adults and children, correlating with a preoperative mortality rate of 5.4%. For patients who underwent intervention, post-procedure mortality was extremely low (0.9%) and attendance of at least one post-procedure review was excellent (99.0%). Eleven (11) (10.9%) patients have required repeat intervention, with no difference in rates between adult and paediatric patients. Length of follow-up extends up to 20 years for some patients. CONCLUSION: The Timor-Leste interventional cohort was predominantly a young female population with rheumatic and congenital cardiac disease. There were also high rates of pregnancy amongst female patients with severe cardiac disease. Delayed access to intervention may result in preoperative adverse events and mortality, and is a key target for improvement. Patients who undergo intervention have very low post-procedural mortality, good adherence to early medical follow-up and good long-term outcomes.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Efeitos Psicossociais da Doença , Cardiopatias Congênitas/epidemiologia , Programas de Rastreamento/métodos , Cardiopatia Reumática/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/economia , Cardiopatias Congênitas/cirurgia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Cardiopatia Reumática/economia , Cardiopatia Reumática/cirurgia , Timor-Leste/epidemiologia , Adulto Jovem
3.
Heart Lung Circ ; 29(1): 149-155, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30686645

RESUMO

BACKGROUND: Off-pump coronary artery bypass grafting (CABG) negates the requirement for extracorporeal circulation used with the traditional on-pump approach. However, off-pump CABG is technically more challenging and may theoretically lead to less complete revascularisation. Recent data suggests a prognostic benefit for traditional on-pump CABG, but the mechanism for this remains unclear. We hypothesised that the inferior outcomes with off-pump CABG could be driven by the need for repeat revascularisation, with this benefit only becoming clear at long-term follow-up. We therefore evaluated short, medium and long-term outcomes of patients undergoing revascularisation with on vs. off-pump CABG. METHODS: Electronic databases were searched to identify suitable randomised controlled trials enrolling ≥100 patients in each arm. Clinical outcomes were extracted at 30-days, 12-months or >4years. The primary outcome was long-term all-cause death, while secondary outcomes included 30-day, 12-month and >4-year cardiac death, stroke, myocardial infarction or revascularisation. RESULTS: Thirteen (13) studies comprising 13,234 patients were included. Off-pump CABG was associated with an increased risk of all-cause death (Odds Ratio [OR] 1.18, 95% confidence interval [CI] 1.02-1.32, p=0.01) and repeat bypass surgery (OR 2.57, 95%CI 1.23-5.39, p=0.01) at long-term follow-up. A significant, increased requirement for revascularisation in off-pump was seen at 12-month follow-up (OR 1.59, 95%CI 1.09-2.33, p=0.02). No differences were noted between groups at 30-days, 12-months and >4years for myocardial infarction or stroke. CONCLUSIONS: Off-pump CABG is associated with significantly higher rates of all-cause mortality rate at long-term follow-up. These outcomes demonstrate a temporal relationship that may be driven by a greater requirement for repeat revascularisation at 1- and 5-year follow-up. STUDY REGISTRATION: CRD42018102019 (PROSPERO).


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Circulação Extracorpórea/efeitos adversos , Infarto do Miocárdio , Acidente Vascular Cerebral , Feminino , Humanos , Masculino , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade
4.
J Environ Sci (China) ; 90: 262-274, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081322

RESUMO

Increasing atmospheric CO2 is both leading to climate change and providing a potential fertilisation effect on plant growth. However, southern Australia has also experienced a significant decline in rainfall over the last 30 years, resulting in increased vegetative water stress. To better understand the dynamics and responses of Australian forest ecosystems to drought and elevated CO2, the magnitude and trend in water use efficiency (WUE) of forests, and their response to drought and elevated CO2 from 1982 to 2014 were analysed, using the best available model estimates constrained by observed fluxes from simulations with fixed and time-varying CO2. The ratio of gross primary productivity (GPP) to evapotranspiration (ET) (WUEe) was used to identify the ecosystem scale WUE, while the ratio of GPP to transpiration (Tr) (WUEc) was used as a measure of canopy scale WUE. WUE increased significantly in northern Australia (p < 0.001) for woody savannas (WSA), whereas there was a slight decline in the WUE of evergreen broadleaf forests (EBF) in the southeast and southwest of Australia. The lag of WUEc to drought was consistent and relatively short and stable between biomes (≤3 months), but notably varied for WUEe, with a long time-lag (mean of 10 months). The dissimilar responses of WUEe and WUEc to climate change for different geographical areas result from the different proportion of Tr in ET. CO2 fertilization and a wetter climate enhanced WUE in northern Australia, whereas drought offset the CO2 fertilization effect in southern Australia.


Assuntos
Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Secas , Florestas , Austrália , Ecossistema , Água
5.
Glob Chang Biol ; 25(5): 1653-1664, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30737866

RESUMO

Prolonged drought and intense heat-related events trigger sudden forest die-off events and have now been reported from all forested continents. Such die-offs are concerning given that drought and heatwave events are forecast to increase in severity and duration as climate change progresses. Quantifying consequences to carbon dynamics and storage from die-off events are critical for determining the current and future mitigation potential of forests. We took stand measurements five times over 2+ years from affected and unaffected plots across the Northern Jarrah Forest, southwestern Australia, following an acute drought/heatwave in 2011. We found a significant loss of live standing carbon (49.3 t ha-1 ), and subsequently a significant increase in the dead standing carbon pool by 6 months post-die-off. Of the persisting live trees, 38% experienced partial mortality contributing to the rapid regrowth and replenishment (82%-88%) of labile carbon pools (foliage, twigs, and branches) within 26 months. Such regrowth was not substantial in terms of net carbon changes within the timeframe of the study but does reflect the resprouting resilience of this forest type. Dead carbon generated by the die-off may persist for centuries given low fragmentation and decay rates resulting in low biogenic emission rates relative to other forest types. However, future fire may threaten persistence of both dead and live pools via combustion and mortality of live tissue and impaired regrowth capacity. Resprouting forests are commonly regarded as resilient systems, however, a changing climate could see vulnerable portions of forests become carbon sources rather than carbon sinks.


Assuntos
Sequestro de Carbono , Secas , Florestas , Árvores/fisiologia , Austrália , Carbono/análise , Mudança Climática , Incêndios , Árvores/química , Árvores/crescimento & desenvolvimento
6.
Glob Chang Biol ; 25(1): 68-77, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30338613

RESUMO

Large-scale planted forests (PF) have been given a higher priority in China for improving the environment and mitigating climate change relative to natural forests (NF). However, the ecological consequences of these PF on water resource security have been less considered in the national scale. Moreover, a critically needed comparison on key ecological effects between PF and NF under climate change has rarely been conducted. Here, we compare carbon sequestration and water consumption in PF and NF across China using combination of remote sensing and field inventory. We found that, on average, NF consumed 6.8% (37.5 mm per growing season) less water but sequestered 1.1% (12.5 g C m-2  growing season-1 ) more carbon than PF in the period of 2000-2012. While there was no significant difference in water consumption (p = 0.6) between PF and NF in energy-limited areas (dryness index [DI] < 1), water consumption was significantly (p < 0.001) higher in PF than that in NF in water-limited regions (DI > 1). Moreover, a distinct and larger shift of water yield was identified in PF than in NF from the 1980s to the 2000s, indicating that PF were more sensitive to climate change, leading to a higher water consumption when compared with NF. Our results suggest NF should be properly valued in terms of maximizing the benefits of carbon sequestration and water yield. Future forest plantation projects should be planned with caution, particularly in water-limited regions where they might have less positive effect on carbon sequestration but lead to significant water yield reduction.


Assuntos
Sequestro de Carbono/fisiologia , Florestas , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Água/metabolismo , Carbono/análise , China , Mudança Climática , Monitoramento Ambiental
7.
J Phys Chem A ; 123(34): 7518-7527, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365257

RESUMO

Soil water repellency (SWR) is an extensively occurring phenomenon on natural and agricultural soils with a severe impact on soil water relations and thus crop yields and ecosystem productivity. It is caused by long chain amphiphilic compounds that originate from plant cuticular waxes. However, the severity of SWR varies with soil physical properties and the concentration of the compounds closely associated with producing hydrophobic coatings on soil surfaces. The induction of SWR by hexadecane, isopropyl tetradecanoate, and palmitic acid (PA), as pure (individual) coatings and as coatings composed of binary mixtures, was investigated by applying a range of loadings on acid-washed sand (AWS) (300-500 µm diameter) and AWS with 5% kaolinite. Molarity of ethanol droplet (MED) tests were conducted to assess the severity of SWR. Palmitic acid was very effective at inducing SWR at loadings of >0.5 × 10-6 mol g-1. Hexadecane and isopropyl tetradecanoate had no effect on SWR when applied as single component coatings. However, when hexadecane was combined with palmitic acid, it enhanced the SWR effect of palmitic acid. In comparison, isopropyl tetradecanoate was found to partially mitigate the SWR caused by palmitic acid. The experimental measurements of SWR were complemented by fully atomistic molecular dynamics simulations that suggested variations of SWR could be explained through molecular level interactions, packing on different soil mineral surfaces and the surface characteristics of the mineral surfaces. In addition, H-donor interactions of PA were found to be instrumental in intermolecular and surface interactions. Furthermore, cohesion and packing of hydrocarbon chains were found to be important parameters favoring surface adhesion, which in turn led to the formation of hydrophobic molecular coatings. The finding that ester derivatives of long chain fatty acids do not induce water repellency suggests that the introduction of chemical or biological processes that promote esterification of fatty acids could be a mechanism for reducing soil water repellency in agricultural soils.

8.
Heart Lung Circ ; 28(10): e134-e136, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31213345

RESUMO

A 73-year-old farmer presented with platypnoea-orthodeoxia syndrome (POS). A transoesophageal echocardiogram (TOE) disclosed a patent foramen ovale (PFO) with significant right-to-left shunt on assuming upright posture. An initial attempt at PFO closure through the femoral vein was abandoned due to a completely occluded inferior vena cava. A second attempt through the internal jugular vein was also unsuccessful due to the steep angulation between superior vena cava and septum primum flap. Because of disabling symptoms, an attempt through a hepatic vein (HV) was scheduled and performed under general anaesthesia with TOE guidance. Ultrasound-guided access through an intercostal window to a peripheral HV was performed and the position confirmed with contrast injections. The PFO was easily crossed with a glide wire which was exchanged to a stiffer guide wire. A 25mm closure device was successfully deployed across the PFO. After retrieval of the delivery system, haemostasis of the HV was attained with a contrast-guided Gelfoam (Pfizer, New York, NY, USA) injection. Unfortunately, the patient had to undergo subsequent emergency coiling to an iatrogenically injured hepatic artery branch leading to full recovery and significant clinical improvement. Subsequent echocardiography demonstrated a well-positioned device with no residual shunt. This case illustrates that percutaneous PFO closure through a HV is a feasible procedure and should be considered in anatomy that is otherwise prohibitive for conventional approach. Extra care should be taken with initial vascular access into the HV and final haemostasis of the access site.


Assuntos
Cateterismo Cardíaco/métodos , Forame Oval Patente/cirurgia , Dispositivo para Oclusão Septal , Cirurgia Assistida por Computador/métodos , Idoso , Ecocardiografia Transesofagiana/métodos , Fluoroscopia , Forame Oval Patente/diagnóstico , Veias Hepáticas , Humanos , Masculino , Tomografia Computadorizada por Raios X
9.
Ann Intern Med ; 166(11): 783-791, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28462421

RESUMO

BACKGROUND: Non-ST-segment elevation acute coronary syndromes include unstable angina and non-ST-segment elevation myocardial infarction. Most randomized controlled trials of routine versus selective invasive coronary angiography have high rates of crossover from control to intervention groups and do not include subgroup analysis for unstable angina. Consequently, no clear, specific recommendations exist regarding the use of angiography in unstable angina. OBJECTIVE: To assess the effect of angiography on mortality in unstable angina, incorporating the results of additional cardiac procedures and events. DESIGN: Longitudinal study using hospital discharge data, discrete-time survival analysis with propensity score adjustment, and sensitivity analysis. SETTING: Victoria, Australia, 2001 to 2011. PARTICIPANTS: All residents, all ages. INTERVENTION: Routine invasive coronary angiography. MEASUREMENTS: 12-month all-cause mortality. RESULTS: Emergently admitted patients with unstable angina (n = 33 901) who did or did not receive angiography during their first hospitalization were balanced on 44 covariates of propensity score. Routine angiography was associated with a 52% decrease in 12-month mortality (hazard ratio, 0.48 [95% CI, 0.38 to 0.61]); revascularization offered no additional statistical mortality benefit compared with diagnostic angiography alone. The predicted cumulative probability of death at 12 months was 0.024 (CI, 0.021 to 0.027) for patients receiving angiography within 2 months of their index unstable angina versus 0.097 (CI, 0.090 to 0.105) for those not receiving it. Sensitivity analysis demonstrated that to negate the observed effect size, an unmeasured confounder must independently decrease mortality by 90% and have a prevalence gap of 15% or greater between the angiographic groups. LIMITATION: Nonrandom allocation of angiography. CONCLUSION: Patients with unstable angina benefit from an invasive management pathway initiated by invasive coronary angiography during their hospitalization and up to 2 months after discharge. PRIMARY FUNDING SOURCES: National Health and Medical Research Council, Australia and BUPA Health Foundation.


Assuntos
Angina Instável/diagnóstico por imagem , Angina Instável/cirurgia , Angiografia Coronária , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/cirurgia , Angina Instável/etiologia , Angina Instável/mortalidade , Pesquisa Comparativa da Efetividade , Ponte de Artéria Coronária , Humanos , Intervenção Coronária Percutânea , Pontuação de Propensão
10.
Heart Lung Circ ; 27(4): 406-419, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29191506

RESUMO

The presence and extent of myocardial ischaemia is a major determinant of prognosis and benefit from revascularisation in patients with stable coronary artery disease. Fractional Flow Reserve (FFR) is accepted as the reference standard for invasive assessment of ischaemia. Its ability to detect lesion specific ischaemia makes it a useful test in a wide range of patient and lesion subsets, with FFR guided intervention improving clinical outcomes and reducing health care costs compared to assessment with coronary angiography alone. This article will review the basic principles in FFR, practical tips in FFR guided revascularisation and the role of emerging non-hyperaemic indices of ischaemia.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Revascularização Miocárdica/normas , Guias de Prática Clínica como Assunto , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/cirurgia , Humanos , Prognóstico
11.
Heart Lung Circ ; 27(4): 451-463, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29291960

RESUMO

BACKGROUND: The Victorian Cardiac Outcomes Registry (VCOR) was established in 2012 to ensure the safety and quality of cardiac based therapies across Victoria. As a clinical quality registry, VCOR monitors the performance of health services in both the public and private sectors, by measuring and reporting on trends in the quality of patient care over time, within individual hospitals, comparatively with other hospitals, and aggregated at the state level. The current paper describes the VCOR registry aims, methods, governance structure and progress to date. METHODS: Primary management of the registry is undertaken at Monash University in association with the Victorian Cardiac Clinical Network, Department of Health and Human Services Victoria. RESULTS: The Victorian Cardiac Outcomes Registry has currently collected data on more than 33,000 cardiac patients across three separate areas of interest in 35 hospitals. These include percutaneous coronary intervention (PCI), the early treatment of acute myocardial infarction in rural and regional settings, and data relating to in-hospital management of heart failure. CONCLUSIONS: The Victorian Cardiac Outcomes Registry is a clinical cardiac registry that commenced data collection in 2013, providing a detailed description of selected aspects of contemporary cardiology clinical practice in a majority of Victorian hospitals. This information enables hospitals and cardiac units to benchmark their practice, clinical outcomes and quality of care to other similar units and hospitals across the state. If replicated by other states in Australia, there will be the potential for important national comparisons, with the goal to foster continuous improvement in patient care and outcomes across the entire Australian health system.


Assuntos
Benchmarking/métodos , Cardiologia/normas , Doenças Cardiovasculares/terapia , Atenção à Saúde/normas , Gerenciamento Clínico , Qualidade da Assistência à Saúde , Sistema de Registros , Doenças Cardiovasculares/epidemiologia , Humanos , Morbidade/tendências , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Vitória/epidemiologia
13.
Glob Chang Biol ; 22(3): 1008-28, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26301476

RESUMO

Soils are subject to varying degrees of direct or indirect human disturbance, constituting a major global change driver. Factoring out natural from direct and indirect human influence is not always straightforward, but some human activities have clear impacts. These include land-use change, land management and land degradation (erosion, compaction, sealing and salinization). The intensity of land use also exerts a great impact on soils, and soils are also subject to indirect impacts arising from human activity, such as acid deposition (sulphur and nitrogen) and heavy metal pollution. In this critical review, we report the state-of-the-art understanding of these global change pressures on soils, identify knowledge gaps and research challenges and highlight actions and policies to minimize adverse environmental impacts arising from these global change drivers. Soils are central to considerations of what constitutes sustainable intensification. Therefore, ensuring that vulnerable and high environmental value soils are considered when protecting important habitats and ecosystems, will help to reduce the pressure on land from global change drivers. To ensure that soils are protected as part of wider environmental efforts, a global soil resilience programme should be considered, to monitor, recover or sustain soil fertility and function, and to enhance the ecosystem services provided by soils. Soils cannot, and should not, be considered in isolation of the ecosystems that they underpin and vice versa. The role of soils in supporting ecosystems and natural capital needs greater recognition. The lasting legacy of the International Year of Soils in 2015 should be to put soils at the centre of policy supporting environmental protection and sustainable development.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Poluição Ambiental/efeitos adversos , Solo
14.
Med J Aust ; 205(3): 114-20, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27465766

RESUMO

BACKGROUND: Variation in the provision of coronary angiography is associated with health care inefficiency and inequity. We explored geographic, socio-economic, health service and disease indicators associated with variation in angiography rates across Australia. METHODS: Australian census and National Health Survey data were used to determine socio-economic, health workforce and service indicators. Hospital separations and coronary deaths during 2011 were identified in the National Hospital Morbidity and Mortality databases. All 61 Medicare Locals responsible for primary care were included, and age- and sex-standardised rates of acute coronary syndrome (ACS) incidence, coronary angiography, revascularisation and mortality were tested for correlations, and adjusted by Bayesian regression. RESULTS: There were 3.7-fold and 2.3-fold differences between individual Medicare Locals in the lowest and highest ACS and coronary artery disease mortality rates respectively, whereas angiography rates varied 5.3-fold. ACS and death rates within Medicare Locals were correlated (partial correlation coefficient [CC], 0.52; P < 0.001). There was modest correlation between ACS and angiography rates (CC, 0.31; P = 0.018). The proportion of patients undergoing angiography who proceeded to revascularisation was inversely correlated with the total angiogram rate (CC, -0.71; P < 0.001). Socio-economic disadvantage and remoteness were correlated with disease burden, ACS incidence and mortality, but not with angiography rate. In the adjusted analysis, the strongest association with local angiography rates was with admissions to private hospitals (71 additional angiograms [95% CI, 47-93] for every 1000 admissions). CONCLUSION: Variation in rates of coronary angiography, not related to clinical need, occurs across Australia. A greater focus on clinical care standards and better distribution of health services will be required if these variations are to be attenuated.


Assuntos
Angiografia Coronária/estatística & dados numéricos , Efeitos Psicossociais da Doença , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Infarto do Miocárdio/diagnóstico por imagem , Austrália , Feminino , Humanos , Masculino , Infarto do Miocárdio/epidemiologia , Índice de Gravidade de Doença , Fatores Socioeconômicos
15.
Med J Aust ; 203(6): 256-8.e1, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26377292

RESUMO

Rising health care costs above inflation are placing serious strains on the sustainability of the Australian Medicare system in its current structure. The Medicare Benefits Schedule (MBS), which lists rebates payable to patients for private medical services provided on a fee-for-service basis, is the cornerstone of the Australian health care system. Introduced in the 1980s, the MBS has changed little despite major advances in the evidence base for the practice of cardiology. We outline how we believe sensible changes to the MBS listings for four cardiac services--invasive coronary angiography, computed tomography coronary angiography, stress testing and percutaneous coronary intervention--would improve the clinical practice of cardiology and save substantial amounts of taxpayer money.


Assuntos
Cardiologia/tendências , Custos de Cuidados de Saúde/tendências , Programas Nacionais de Saúde/legislação & jurisprudência , Austrália , Cardiologia/economia , Angiografia Coronária/economia , Teste de Esforço/economia , Humanos , Programas Nacionais de Saúde/economia , Intervenção Coronária Percutânea/economia , Impostos/economia , Tomografia Computadorizada por Raios X/economia
16.
Heart Lung Circ ; 24(12): 1162-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26361818

RESUMO

Transcatheter aortic valve implantation (TAVI) is a rapidly evolving field with exponential growth worldwide in TAVI numbers. One of the principle methods in improving outcomes with a new technique such as TAVI is to ensure that patients undergo efficient pre-procedural evaluation. Standard TAVI workup includes clinical assessment, surgical and frailty risk scoring, blood investigations, echocardiography, pulmonary function tests, computed tomography (CT) angiography and cardiac catheterisation. Patients sent to the cardiac catheterisation laboratory (CCL) for TAVI workup require a systematic and thorough approach. This can include iliofemoral angiography, aortography, aortic valve crossing, haemodynamic evaluation, coronary angiography and right heart catheterisation. In addition, several key steps are required to evaluate suitability for the percutaneous transfemoral TAVI approach. This is the first review to systematically describe steps to evaluate pre-TAVI patients in the CCL. Due to the rapidly rising TAVI numbers, this workup will likely be performed not only by TAVI operators but also by the general interventional cardiologist.


Assuntos
Angiografia/métodos , Cuidados Pré-Operatórios/métodos , Tomografia Computadorizada por Raios X/métodos , Substituição da Valva Aórtica Transcateter/métodos , Humanos
17.
Glob Chang Biol ; 20(10): 3270-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24700759

RESUMO

The agriculture, forestry and other land use (AFOLU) sector is responsible for approximately 25% of anthropogenic GHG emissions mainly from deforestation and agricultural emissions from livestock, soil and nutrient management. Mitigation from the sector is thus extremely important in meeting emission reduction targets. The sector offers a variety of cost-competitive mitigation options with most analyses indicating a decline in emissions largely due to decreasing deforestation rates. Sustainability criteria are needed to guide development and implementation of AFOLU mitigation measures with particular focus on multifunctional systems that allow the delivery of multiple services from land. It is striking that almost all of the positive and negative impacts, opportunities and barriers are context specific, precluding generic statements about which AFOLU mitigation measures have the greatest promise at a global scale. This finding underlines the importance of considering each mitigation strategy on a case-by-case basis, systemic effects when implementing mitigation options on the national scale, and suggests that policies need to be flexible enough to allow such assessments. National and international agricultural and forest (climate) policies have the potential to alter the opportunity costs of specific land uses in ways that increase opportunities or barriers for attaining climate change mitigation goals. Policies governing practices in agriculture and in forest conservation and management need to account for both effective mitigation and adaptation and can help to orient practices in agriculture and in forestry towards global sharing of innovative technologies for the efficient use of land resources. Different policy instruments, especially economic incentives and regulatory approaches, are currently being applied however, for its successful implementation it is critical to understand how land-use decisions are made and how new social, political and economic forces in the future will influence this process.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Agricultura Florestal , Políticas , Agricultura , Animais , Gases , Efeito Estufa/prevenção & controle , Gado , Solo
18.
Eur Radiol ; 24(3): 738-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24217643

RESUMO

OBJECTIVES: To determine the accuracy of 320-row multidetector coronary computed tomography angiography (M320-CCTA) to detect functional stenoses using fractional flow reserve (FFR) as the reference standard and to predict revascularisation in stable coronary artery disease. METHODS: One hundred and fifteen patients (230 vessels) underwent M320-CCTA and FFR assessment and were followed for 18 months. Diameter stenosis on invasive angiography (ICA) and M320-CCTA were assessed by consensus by two observers and significant stenosis was defined as ≥50%. FFR ≤0.8 indicated functionally significant stenoses. RESULTS: M320-CCTA had 94% sensitivity and 94% negative predictive value (NPV) for FFR ≤0.8. Overall accuracy was 70%, specificity 54% and positive predictive value 65%. On receiver operating characteristic (ROC) curve analysis, the area under the curve (AUC) for CCTA to predict FFR ≤0.8 was 0.74 which was comparable with ICA. The absence of a significant stenosis on M320-CCTA was associated with a 6% revascularisation rate. M320-CCTA predicted revascularisation with an AUC of 0.71 which was comparable with ICA. CONCLUSIONS: M320-CCTA has excellent sensitivity and NPV for functional stenoses and therefore may act as an effective gatekeeper to defer ICA and revascularisation. Like ICA, M320-CCTA lacks specificity for functional stenoses and only has moderate accuracy to predict the need for revascularisation. KEY POINTS: • Important information about the heart is provided by 320-row multidetector CT coronary angiography (M320-CCTA). • M320-CCTA accurately detects and excludes functional stenoses determined by fractional flow reserve (FFR). • Non-significant stenoses on M320-CCTA associated with fewer cardiac events and less revascularisation. • M320-CCTA may act as a gatekeeper for invasive angiography and inappropriate revascularisation. • Like ICA, M320-CCTA only has moderate accuracy to predict vessels requiring revascularisation.


Assuntos
Angiografia Coronária/normas , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Tomografia Computadorizada Multidetectores/normas , Idoso , Angina Pectoris/diagnóstico por imagem , Área Sob a Curva , Angiografia Coronária/instrumentação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
19.
Heart Lung Circ ; 23(2): 127-31, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24012104

RESUMO

BACKGROUND: Transcatheter closure of moderate sized atrial septal defects (ASD) has been demonstrated to be safe and effective. However, the feasibility of transcatheter closure of very large defects is less clear, particularly when an aortic rim of septal tissue is absent. METHODS: The study included patients referred for transcatheter ASD closure with maximal ASD diameter ≥ 20 mm at pre-procedural transoesophageal echocardiography. Patients were grouped according to presence of moderately large (20-29 mm), very large (30-39 mm), or extremely large (≥ 40 mm) ASD size. Procedural success was defined by successful device deployment and absence of complications. RESULTS: Forty-two patients (median age 40 years, range 12-85 years, 76% female) were included in the study. The mean maximal ASD diameter was 29.0 ± 7.4mm. Twenty-three patients had moderately large ASDs (23.0 ± 2.8mm); 13 had very large ASDs (33.1 ± 2.9 mm) and six had extremely large ASDs (41.3 ± 1.6 mm). The aortic rim was absent in 22 patients, and present in 20 patients (4.7 ± 2.9 mm). Transcatheter defect closure was successful in 36 of 42 patients (86%). Procedural success was 100% in the moderately large ASD group, 92% in the very large group but only 17% (one out of six) in the extremely large group. If patients with ASD ≥ 40 mm were excluded (n = 6), the overall success rate was 97%. A single complication (device dislodgement) occurred in a patient with a 42 mm defect and a deficient postero-inferior rim. The presence or absence of an aortic rim of septum did not influence procedural success. CONCLUSION: The vast majority (97%) of large ASDs in the range 20-39 mm can be successfully closed percutaneously with a low or zero complication rate. However, procedural success is poor when attempting closure of extreme defects (≥ 40 mm), regardless of whether an aortic rim of septal tissue or present or absent.


Assuntos
Cateterismo Cardíaco/métodos , Ecocardiografia Transesofagiana , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interatrial/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
20.
Heart Lung Circ ; 23(11): e240-3, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25082307

RESUMO

We report a case of a 54 year-old man with osteogenesis imperfecta who developed severe para-valvular mitral regurgitation after a second heart operation to correct the same problem. The large para-valvular leak was successfully closed with an Amplatzer Vascular Plug III delivered from the apical approach.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares/efeitos adversos , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia , Osteogênese Imperfeita/cirurgia , Complicações Pós-Operatórias/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA