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1.
J Nucl Med Technol ; 51(2): 90-98, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37268318

RESUMO

99mTc-pyrophosphate imaging has been around for a long time. In the 1970s, it was used to image recent myocardial infarction. However, it has recently been recognized for its value in detecting cardiac amyloidosis, leading to widespread use across the United States. Increased use led to considerable procedure variability. As the evidence base to support formal guidelines was being developed, experts from several professional medical societies issued imaging and interpretation recommendations titled "ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI Expert Consensus Recommendations for Multimodality Imaging in Cardiac Amyloidosis: part 1 of 2-Evidence Base and Standardized Methods of Imaging." To reach a consensus on a protocol that would benefit the bulk of laboratories, the experts considered several parameters and radiotracer kinetics. The most critical parameters concerned injection-to-imaging delay and planar imaging versus SPECT. Accordingly, the standardized protocol recommends the injection of 370-740 MBq (10-20 mCi) of 99mTc-pyrophosphate with imaging 3 h later. Planar images of the chest are acquired in the anterior and lateral views accompanied by SPECT images. Both the planar and the SPECT images are used to semiquantitatively grade the degree of myocardial uptake compared with the amount of uptake in the ribs using a 0-3 scale. A grade of 2 or 3 on the SPECT images is considered positive for cardiac amyloidosis. The planar images are used to calculate a heart-to-contralateral-lung ratio. A ratio greater than 1.3 at 3 h helps to confirm the diagnosis of cardiac amyloid if the SPECT images have positive findings. This article is part of a 3-part series in this issue of the Journal of Nuclear Medicine Technology Part 1 details the etiology of cardiac amyloidosis and 99mTc-pyrophosphate imaging acquisition parameters. Part 2, this article, describes the procedure evolution over 50 y, image processing, and quantification. It further discusses radiotracer kinetics and 2 important technical considerations: injection-to-imaging delay and planar imaging versus SPECT. Part 3 covers study interpretation along with cardiac amyloidosis diagnosis and treatment.


Assuntos
Amiloidose , Cardiomiopatias , Humanos , Estados Unidos , Difosfatos , Amiloidose/diagnóstico por imagem , Amiloidose/terapia , Coração
2.
J Nucl Med Technol ; 51(2): 83-89, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37268319

RESUMO

Cardiac amyloidosis is a systemic form of amyloidosis in which protein-based infiltrates are deposited in myocardial extracellular space. The accumulation of amyloid fibrils causes the myocardium to thicken and stiffen, leading to diastolic dysfunction and, eventually, heart failure. Until recently, cardiac amyloidosis was considered rare. However, the recent adoption of noninvasive diagnostic testing, including 99mTc-pyrophosphate imaging, has revealed a previously undiagnosed sizable disease prevalence. Light-chain amyloidosis (AL) and transthyretin amyloidosis (ATTR), the 2 primary types, account for 95% of cardiac amyloidosis diagnoses. AL results from plasma cell dyscrasia and has a very poor prognosis. The usual treatment for cardiac AL is chemotherapy and immunotherapy. Cardiac ATTR is more chronic, usually resulting from age-related instability and misfolding of the transthyretin protein. ATTR is treated by managing heart failure and using new pharmacotherapeutic drugs. 99mTc-pyrophosphate imaging can efficiently and effectively distinguish between ATTR and cardiac AL. Although the exact mechanism of myocardial 99mTc-pyrophosphate uptake is unknown, it is believed to bind to amyloid plaque microcalcifications. 99mTc-pyrophosphate imaging has a 97% sensitivity and nearly 100% sensitivity for identifying cardiac ATTR when the AL form of the disease is ruled out through serum free light-chain and serum and urine protein electrophoresis with immunofixation testing. Although there are no published 99mTc-pyrophosphate cardiac amyloidosis imaging guidelines, the American Society of Nuclear Cardiology, Society of Nuclear Medicine and Molecular Imaging, and others have published consensus recommendations to standardize test performance and interpretation. This article, part 1 of a 3-part series in this issue of the Journal of Nuclear Medicine Technology, describes amyloidosis etiology and cardiac amyloidosis characteristics, including the types, prevalence, signs and symptoms, and disease course. It further explains the scan acquisition protocol. Part 2 of the series focuses on image/data quantification and technical considerations. Finally, part 3 describes scan interpretation, along with the diagnosis and treatment of cardiac amyloidosis.


Assuntos
Neuropatias Amiloides Familiares , Insuficiência Cardíaca , Humanos , Difosfatos , Coração , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/diagnóstico por imagem
3.
J Nucl Med Technol ; 51(2): 102-116, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37268322

RESUMO

Cardiac amyloidosis was thought to be rare, undiagnosable, and incurable. However, recently it has been discovered to be common, diagnosable, and treatable. This knowledge has led to a resurgence in nuclear imaging with 99mTc-pyrophosphate-a scan once believed to be extinct-to identify cardiac amyloidosis, particularly in patients with heart failure but preserved ejection fraction. The renewed interest in 99mTc-pyrophosphate imaging has compelled technologists and physicians to reacquaint themselves with the procedure. Although 99mTc-pyrophosphate imaging is relatively simple, interpretation and diagnostic accuracy require an in-depth knowledge of amyloidosis etiology, clinical manifestations, disease progression, and treatment. Diagnosing cardiac amyloidosis is complicated because typical signs and symptoms are nonspecific and usually attributed to other cardiac disorders. In addition, physicians must be able to differentiate between monoclonal immunoglobulin light-chain amyloidosis (AL) and transthyretin amyloidosis (ATTR). Several clinical and noninvasive diagnostic imaging (echocardiography and cardiac MRI) red flags have been identified that suggest a patient may have cardiac amyloidosis. The intent of these red flags is to raise physician suspicion of cardiac amyloidosis and guide a series of steps (a diagnostic algorithm) for narrowing down and diagnosing the specific amyloid type. One element in the diagnostic algorithm is to identify monoclonal proteins indicative of AL. Monoclonal proteins are detected by serum or urine immunofixation electrophoresis and serum free light-chain assay. Another element is identifying and grading cardiac amyloid deposition using 99mTc-pyrophosphate imaging. When monoclonal proteins are present and the 99mTc-pyrophosphate scan is positive, the patient should be further evaluated for cardiac AL. The absence of monoclonal proteins and a positive 99mTc-pyrophosphate scan is diagnostic for cardiac ATTR. Patients with cardiac ATTR need to undergo genetic testing to differentiate between wild-type ATTR and variant ATTR. This article is the third in a 3-part series in this issue of the Journal of Nuclear Medicine Technology Part 1 reviewed amyloidosis etiology and outlined 99mTc-pyrophosphate study acquisition. Part 2 described 99mTc-pyrophosphate image quantification and protocol technical considerations. This article discusses scan interpretation along with cardiac amyloidosis diagnosis and treatment.


Assuntos
Neuropatias Amiloides Familiares , Cardiomiopatias , Humanos , Difosfatos , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/terapia , Compostos Radiofarmacêuticos , Neuropatias Amiloides Familiares/diagnóstico por imagem , Neuropatias Amiloides Familiares/terapia , Cintilografia
4.
Wilderness Environ Med ; 33(1): 92-96, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35000867

RESUMO

INTRODUCTION: Every March, dogsled drivers (mushers) compete in a 1569-km race across Alaska, involving physical exertion, mental exertion, and sleep deprivation for up to 2 wk. These factors may increase mushers' vulnerability to illness, making them a relevant study population for acute infection risk factors. Specifically, the influence of psychological factors on illness risk during prolonged physical exertion has rarely been investigated. The aim of this study was to examine the relationship between psychological characteristics, sleep deprivation, and illness incidence in Iditarod mushers. METHODS: Fourteen mushers completed 4 psychological instruments to assess state and trait anxiety, resilience and perceived stress, and self-reported upper respiratory symptoms (URS) in the month before the race. Mushers self-reported sleep duration and URS during the race. RESULTS: State and trait anxiety, resilience, and perceived stress did not differ between mushers with and without pre- and in-race URS (P>0.05). However, all mushers who reported in-race URS had reported URS ≤9 d before the race, and the onset of symptoms during the race typically occurred shortly after a rest period. Sleep duration was higher in mushers who reported in-race URS, both before (4.9±0.3 h, P=0.016) and during illness (5.9±1.3 h, P=0.006), vs mushers without in-race URS (3.4±0.8 h). CONCLUSIONS: This study highlights recent illness, rest periods, and greater sleep requirements as potential risk factors for URS onset during a multiday endurance challenge, whereas psychological factors were not associated with URS.


Assuntos
Privação do Sono , Sono , Alaska/epidemiologia , Animais , Cães , Humanos , Incidência , Esforço Físico , Privação do Sono/epidemiologia
5.
Front Cardiovasc Med ; 8: 684780, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336948

RESUMO

Since the first reported case of COVID-19 in December 2019, the global landscape has shifted toward an unrecognizable paradigm. The sports world has not been immune to these ramifications; all major sports leagues have had abbreviated seasons, fan attendance has been eradicated, and athletes have opted out of entire seasons. For these athletes, cardiovascular complications of COVID-19 are particularly concerning, as myocarditis has been implicated in a significant portion of sudden cardiac death (SCD) in athletes (up to 22%). Multiple studies have attempted to evaluate post-COVID myocarditis and develop consensus return-to-play (RTP) guidelines, which has led to conflicting information for internists and primary care doctors advising these athletes. We aim to review the pathophysiology and diagnosis of viral myocarditis, discuss the heterogeneity regarding incidence of COVID myocarditis among athletes, and summarize the current expert recommendations for RTP. The goal is to provide guidance for practitioners who will be managing and advising athletes in the COVID era.

6.
Environ Int ; 156: 106767, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34425643

RESUMO

Particulate matter 2.5 (PM2.5) exposure induces oxidative stress associated with many negative health outcomes such as respiratory disorders, cardiovascular disease and neurodegenerative disease. Research shows that diet and exercise can improve antioxidant defense against oxidative stress. This study is the first to use an Arctic animal model to investigate the cumulative effects of two lifestyle interventions on the antioxidant response before, during, and after ambient PM 2.5 exposure from wildfire: antioxidant supplementation (Arthrospira platensis) and exercise. In a two-factorial, longitudinal design, this study divided sled dogs (n = 48) into four groups (exercise and supplemented, exercise, supplemented, and control) to (1) test the effects of a 30-day exercise and antioxidant supplementation protocol on antioxidant response; and (2) measure the antioxidant response of all groups during and after a natural wildfire event. Commercial assays for total antioxidant power (TAP) and the enzymatic antioxidant superoxide dismutase (SOD) were used as markers for antioxidant status and response. During the forest fire, SOD was increased 5- to 10-fold over pre/post-exposure levels in all groups suggesting an endogenous upregulation of defense systems in response to the acute environmental stress. TAP was lower in all groups at peak PM2.5 exposure compared to 48 h after peak exposure in all groups except the exercise alone group which may indicate that exercise offers improved endogenous defense.


Assuntos
Doenças Neurodegenerativas , Incêndios Florestais , Alaska , Animais , Cães , Material Particulado/análise , Material Particulado/toxicidade , Spirulina
7.
JACC Cardiovasc Imaging ; 14(9): 1819-1828, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33454257

RESUMO

OBJECTIVES: This study sought to describe worldwide variations in the use of myocardial perfusion imaging hardware, software, and imaging protocols and their impact on radiation effective dose (ED). BACKGROUND: Concerns about long-term effects of ionizing radiation have prompted efforts to identify strategies for dose optimization in myocardial perfusion scintigraphy. Studies have increasingly shown opportunities for dose reduction using newer technologies and optimized protocols. METHODS: Data were submitted voluntarily to the INCAPS (International Atomic Energy Agency Nuclear Cardiology Protocols Study) registry, a multinational, cross-sectional study comprising 7,911 imaging studies from 308 labs in 65 countries. The study compared regional use of camera technologies, advanced post-processing software, and protocol characteristics and analyzed the influence of each factor on ED. RESULTS: Cadmium-zinc-telluride and positron emission tomography (PET) cameras were used in 10% (regional range 0% to 26%) and 6% (regional range 0% to 17%) of studies worldwide. Attenuation correction was used in 26% of cases (range 10% to 57%), and advanced post-processing software was used in 38% of cases (range 26% to 64%). Stress-first single-photon emission computed tomography (SPECT) imaging comprised nearly 20% of cases from all world regions, except North America, where it was used in just 7% of cases. Factors associated with lower ED and odds ratio for achieving radiation dose ≤9 mSv included use of cadmium-zinc-telluride, PET, advanced post-processing software, and stress- or rest-only imaging. Overall, 39% of all studies (97% PET and 35% SPECT) were ≤9 mSv, while just 6% of all studies (32% PET and 4% SPECT) achieved a dose ≤3 mSv. CONCLUSIONS: Newer-technology cameras, advanced software, and stress-only protocols were associated with reduced ED, but worldwide adoption of these practices was generally low and varied significantly between regions. The implementation of dose-optimizing technologies and protocols offers an opportunity to reduce patient radiation exposure across all world regions.


Assuntos
Cardiologia , Imagem de Perfusão do Miocárdio , Estudos Transversais , Humanos , Valor Preditivo dos Testes , Doses de Radiação , Software , Tecnologia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
8.
JACC Cardiovasc Imaging ; 14(3): 657-665, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32828783

RESUMO

OBJECTIVES: This study sought to establish worldwide and regional diagnostic reference levels (DRLs) and achievable administered activities (AAAs) for single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). BACKGROUND: Reference levels serve as radiation dose benchmarks to compare individual laboratories against aggregated data, helping to identify sites in greatest need of dose reduction interventions. DRLs for SPECT MPI have previously been derived from national or regional registries. To date there have been no multiregional reports of DRLs for SPECT MPI from a single standardized dataset. METHODS: Data were submitted voluntarily to the INCAPS (International Atomic Energy Agency Nuclear Cardiology Protocols Study), a cross-sectional, multinational registry of MPI protocols. A total of 7,103 studies were included. DRLs and AAAs were calculated by protocol for each world region and for aggregated worldwide data. RESULTS: The aggregated worldwide DRLs for rest-stress or stress-rest studies employing technetium Tc 99m-labeled radiopharmaceuticals were 11.2 mCi (first dose) and 32.0 mCi (second dose) for 1-day protocols, and 23.0 mCi (first dose) and 24.0 mCi (second dose) for multiday protocols. Corresponding AAAs were 10.1 mCi (first dose) and 28.0 mCi (second dose) for 1-day protocols, and 17.8 mCi (first dose) and 18.7 mCi (second dose) for multiday protocols. For stress-only technetium Tc 99m studies, the worldwide DRL and AAA were 18.0 mCi and 12.5 mCi, respectively. Stress-first imaging was used in 26% to 92% of regional studies except in North America where it was used in just 7% of cases. Significant differences in DRLs and AAAs were observed between regions. CONCLUSIONS: This study reports reference levels for SPECT MPI for each major world region from one of the largest international registries of clinical MPI studies. Regional DRLs may be useful in establishing or revising guidelines or simply comparing individual laboratory protocols to regional trends. Organizations should continue to focus on establishing standardized reporting methods to improve the validity and comparability of regional DRLs.


Assuntos
Níveis de Referência de Diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único , Estudos Transversais , Humanos , Perfusão , Valor Preditivo dos Testes , Doses de Radiação
9.
Circ Cardiovasc Imaging ; 11(12): e007565, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30558499

RESUMO

BACKGROUND: Radiation exposure during nuclear cardiology procedures has received much attention and has prompted citations for radiation reduction. In 2010, the American Society of Nuclear Cardiology recommended reducing the average patient study radiation exposure to <9 mSv in 50% of studies by 2014. Cardiac positron emission tomography (PET) for myocardial perfusion imaging (MPI) has emerged within recent years, but current radiation exposure in cardiac nuclear PET laboratories is unknown. This study evaluated current reported patient radiation exposure from nuclear laboratories in the United States applying for Intersocietal Accreditation Commission accreditation for MPI using single photon emission computed tomography (SPECT) or PET. METHODS AND RESULTS: This was an analysis of nuclear cardiology studies submitted to the Intersocietal Accreditation Commission for either or both cardiac PET and SPECT accreditation. Cardiac SPECT data represented year 2015 while PET data combined years 2013 to 2015. Data was analyzed with χ2 and Mann-Whitney U tests (reported as median, 25th percentile, and 75th percentile). Reported PET MPI radiation exposure for 111 laboratories (532 patient cases) was 3.7 (3.2-4.1) mSv per study with no geographic variation. Reported SPECT MPI radiation exposure for 665 laboratories (3067 patient studies) was 12.8 (12.2-14.3) mSv. Highest radiation exposure was found in the South region. Technetium-only studies resulted in a median of 12.2 mSv per study. CONCLUSIONS: Radiation exposure from cardiac PET MPI in US laboratories applying for Intersocietal Accreditation Commission accreditation is low (111 laboratories, 3.7 mSv) and substantially lower than cardiac SPECT (665 laboratories, 12.8 mSv).


Assuntos
Cardiopatias/diagnóstico , Imagem de Perfusão do Miocárdio/métodos , Segurança do Paciente/normas , Lesões por Radiação/epidemiologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Humanos , Incidência , Doses de Radiação , Exposição à Radiação , Lesões por Radiação/prevenção & controle , Estudos Retrospectivos , Estados Unidos/epidemiologia
10.
Med Sci Sports Exerc ; 50(5): 938-944, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29271848

RESUMO

PURPOSE: Glucose transporter 4 (GLUT4) plays a key role in the pathophysiology of type 2 diabetes. Glucose transporter 4 is upregulated in response to exercise, enhancing cellular glucose transport in skeletal muscle tissue. This mechanism appears to remain intact in individuals with insulin resistance. Details of the mechanism are poorly understood and are challenging to study due to the invasive nature of muscle biopsy. Peripheral blood mononuclear cells (PBMC) have documented insulin-sensitive GLUT4 activity and may serve as a proxy tissue for studying skeletal muscle GLUT4. The purpose of this study was to investigate whether GLUT4 in PBMC is affected by conditioning. METHODS: We recruited 16 student athletes from the cross-country running and skiing teams and fifteen sedentary students matched for age and sex from the University of Alaska Fairbanks. Peripheral blood mononuclear cells were collected with mononuclear cell separation tubes. The GLUT4 concentrations were measured using a commercially available enzyme linked immunosorbent assay. Additionally, correlations between PBMC GLUT4 and common indicators of insulin resistance were examined. RESULTS: Results indicate significantly higher PBMC GLUT4 levels in conditioned athletes than in their sedentary counterparts, similar to what has been documented in myocytes. Females were observed to have higher PBMC GLUT4 levels than males. Correlations were not detected between PBMC GLUT4 and hemoglobin A1c, glucose, insulin, homeostatic model assessment of insulin resistance, body mass index, or body fat. CONCLUSIONS: This study provides evidence to support exploration of PBMC as a proxy tissue for studying GLUT4 response to exercise or other noninsulin factors.


Assuntos
Exercício Físico , Transportador de Glucose Tipo 4/metabolismo , Leucócitos Mononucleares/metabolismo , Adiposidade , Atletas , Glicemia/análise , Índice de Massa Corporal , Feminino , Hemoglobinas Glicadas/análise , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Músculo Esquelético/fisiologia , Comportamento Sedentário , Adulto Jovem
11.
J Nucl Cardiol ; 25(1): 86-93, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26797922

RESUMO

A common clinical conundrum presents itself in the discordance between nuclear stress testing and invasive coronary angiography (ICA) in the patient presenting with angina. A patient with an abnormal perfusion scan and "normal coronary angiography" may result in the patient's symptoms being dismissed as "non-cardiac." Alternatively, a patient with a "normal perfusion study," who nonetheless undergoes ICA and is found to have significant coronary artery disease may confound efforts to risk stratify and potentially treat patients with angina. This paper will review the current evidence to explain these apparent paradoxical scenarios.


Assuntos
Angina Estável/diagnóstico por imagem , Angina Instável/diagnóstico por imagem , Angiografia Coronária , Imagem de Perfusão do Miocárdio , Angiografia por Tomografia Computadorizada , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Teste de Esforço , Reserva Fracionada de Fluxo Miocárdico , Humanos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/mortalidade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco
12.
J Cardiovasc Comput Tomogr ; 11(5): 404-414, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28867495

RESUMO

The rising cost of healthcare is prompting numerous policy and advocacy discussions regarding strategies for constraining growth and creating a more efficient and effective healthcare system. Cardiovascular imaging is central to the care of patients at risk of, and living with, heart disease. Estimates are that utilization of cardiovascular imaging exceeds 20 million studies per year. The Society of Cardiovascular CT (SCCT), alongside Rush University Medical Center, and in collaboration with government agencies, regional payers, and industry healthcare experts met in November 2016 in Chicago, IL to evaluate obstacles and hurdles facing the cardiovascular imaging community and how they can contribute to efficacy while maintaining or even improving outcomes and quality. The summit incorporated inputs from payers, providers, and patients' perspectives, providing a platform for all voices to be heard, allowing for a constructive dialogue with potential solutions moving forward. This article outlines the proceedings from the summit, with a detailed review of past hurdles, current status, and potential solutions as we move forward in an ever-changing healthcare landscape.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Política de Saúde/legislação & jurisprudência , Cardiopatias/diagnóstico por imagem , Formulação de Políticas , Serviços Preventivos de Saúde/legislação & jurisprudência , Angiografia por Tomografia Computadorizada/economia , Angiografia por Tomografia Computadorizada/normas , Consenso , Angiografia Coronária/economia , Angiografia Coronária/normas , Redução de Custos , Análise Custo-Benefício , Medicina Baseada em Evidências/legislação & jurisprudência , Medicina Baseada em Evidências/normas , Custos de Cuidados de Saúde/legislação & jurisprudência , Política de Saúde/economia , Cardiopatias/economia , Cardiopatias/prevenção & controle , Humanos , Valor Preditivo dos Testes , Serviços Preventivos de Saúde/economia , Serviços Preventivos de Saúde/normas , Participação dos Interessados
13.
Int J Circumpolar Health ; 76(1): 1314414, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28452288

RESUMO

PURPOSE: 25-hydroxyvitamin D (25[OH]D) deficiency is associated with compromised bone mineralisation, fatigue, suppressed immune function and unsatisfactory skeletal muscle recovery. We investigated the risk of 25(OH)D insufficiency or deficiency in endurance athletes compared to sedentary non-athletes living at 64° north. METHODS: University student-athletes (TS) and sedentary students (SS) volunteered to participate in this study. TS engaged in regular exercise while SS exercised no more than 20 minutes/week. Metabolic Equivalent of Task (MET) scores for participants were determined. Vitamin D intake was assessed using the National Cancer Institute's 24-hour food recall (ASA24). Fasting plasma 25(OH)D levels were quantified via enzyme-linked immunosorbent assay. RESULTS: TS reported higher activity levels than SS as assessed with MET-minutes/week and ranking of physical activity levels (p < 0.05). The reported mean daily intake of vitamin D was higher in TS compared to SS (p < 0.05) while 25(OH)D plasma levels were lower in TS than in SS (p < 0.05). In total, 43.8% of the TS were either insufficient (31.3%) or deficient (12.5%) in 25(OH)D, while none of the SS were insufficient and 13.3% were deficient. CONCLUSION: TS are at increased risk of 25(OH)D insufficiency or deficiency compared to their sedentary counterparts residing at the same latitude, despite higher vitamin D intake.


Assuntos
Atletas/estatística & dados numéricos , Comportamento Sedentário , Deficiência de Vitamina D/epidemiologia , Vitamina D/administração & dosagem , Adolescente , Adulto , Regiões Árticas , Pesos e Medidas Corporais , Dieta/estatística & dados numéricos , Suplementos Nutricionais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Equivalente Metabólico , Estudantes , Luz Solar , Universidades , Deficiência de Vitamina D/sangue , Adulto Jovem
14.
Heart Lung Circ ; 26(1): 25-34, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27425184

RESUMO

BACKGROUND: There is concern about radiation exposure with radionuclide myocardial perfusion imaging (MPI). This sub-study of the International Atomic Energy Agency (IAEA) Nuclear Cardiology Protocols Study reports radiation doses from MPI, and use of dose-optimisation protocols in Australia and New Zealand (ANZ), and compares them with data from the rest of the world. METHODS: Data were collected from 7911 MPI studies performed in 308 laboratories worldwide in one week in 2013, including 439 MPI studies from 34 ANZ laboratories. For each laboratory, effective radiation dose (ED) and a quality index (QI) score (out of 8) based on pre-specified "best practices" was determined. RESULTS: In ANZ patients, ED ranged from 0.9-17.9 milliSievert (mSv). Median ED was similar in ANZ compared with the rest of the world (10.0 (IQR: 6.5-11.7) vs. 10.0 (IQR 6.4-12.6, P=0.15), as were mean QI scores (5.5±0.7 vs. 5.4±1.3, P=0.84). Use of stress-only imaging (17.6% vs. 31.8% of labs, P=0.09) and weight-based dosing of technetium-99m (14.7% vs. 30.3%, P=0.07) was lower in ANZ compared with the rest of the world but this difference was not statistically significant. Median ED was significantly lower in metropolitan versus non-metropolitan laboratories (10.1 mSv vs. 11.6 mSv, P<0.01), although mean QI scores were similar (5.4±0.8 vs. 5.5±0.7, P=0.75). CONCLUSION: Across ANZ, there is variability in ED from MPI, and use of radiation safety practices, particularly between metropolitan and non-metropolitan laboratories. Overall, ANZ laboratories have a similar median ED to laboratories in the rest of the world.


Assuntos
Imagem de Perfusão do Miocárdio/efeitos adversos , Doses de Radiação , Exposição à Radiação , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oceania
16.
JACC Cardiovasc Imaging ; 8(10): 1170-1176, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26363837

RESUMO

OBJECTIVES: This study sought to examine current laboratory practices for radiation effective doses for myocardial perfusion imaging (MPI) and laboratory adherence to guideline-directed radiation reduction practices. BACKGROUND: A recent focus on radiation dose reduction for cardiovascular imaging has led to several published guidelines and consensus statements detailing performance metrics for laboratory practices. We sought to examine laboratory adherence to optimized radiation dose protocol recommendations among 5,216 submitted cases from 1,074 MPI laboratories evaluated for Intersocietal Accreditation Commission accreditation. METHODS: Eligible imaging centers included MPI laboratories enrolled in the Intersocietal Accreditation Commission data repository of accreditation applications from 2012 to 2013. Accreditation requires submission of 3 to 5 cases for evaluation of a range of representative cases. Based on standard dosimetry for rest and stress MPI, an effective dose (in millisieverts) was calculated. Model simulations were performed to estimate guideline-directed effective doses. RESULTS: The average effective dose was 14.9 ± 5.8 mSv (range 1.4 to 42.4 mSv). A 1-day technetium Tc 99m protocol was used in 82.9% of cases, whereas a 2-day technetium Tc 99m and dual isotope protocol was used in 7.5% of submitted cases. Only 1.5% of participating imaging centers met current guidelines for an average laboratory radiation exposure ≤9 mSv, whereas 10.1% of patient effective doses were >20.0 mSv. A model simulation replacing the radiation exposure of dual isotope MPI with that of a 1-day technetium Tc 99m protocol reduced the proportion of patients receiving an effective dose >20 mSv to only 2.7% of cases (p < 0.0001). CONCLUSIONS: Mandatory laboratory accreditation for MPI allows for examination of current radiation dosimetry practices. Current guidelines for reduced patient-specific radiation exposure are rarely implemented, with few laboratories meeting recommendations of ≤9 mSv for 50% of patients. Increased educational efforts and the development of performance measures for laboratory accreditation may be required to meet current radiation dose-reduction standards.


Assuntos
Acreditação/normas , Técnicas de Laboratório Clínico/normas , Fidelidade a Diretrizes/normas , Cardiopatias/diagnóstico por imagem , Ensaio de Proficiência Laboratorial/normas , Imagem de Perfusão do Miocárdio/normas , Guias de Prática Clínica como Assunto/normas , Doses de Radiação , Exposição à Radiação/normas , Compostos Radiofarmacêuticos/normas , Simulação por Computador , Circulação Coronária , Bases de Dados Factuais , Cardiopatias/fisiopatologia , Humanos , Imagem de Perfusão do Miocárdio/métodos , Variações Dependentes do Observador , Compostos Organofosforados/normas , Compostos de Organotecnécio/normas , Valor Preditivo dos Testes , Exposição à Radiação/prevenção & controle , Compostos Radiofarmacêuticos/administração & dosagem , Reprodutibilidade dos Testes , Tecnécio Tc 99m Sestamibi/normas , Estados Unidos
17.
Clin Cardiol ; 38(7): 401-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26072711

RESUMO

The Intersocietal Accreditation Commission (IAC) accredits vascular, echocardiography, nuclear medicine, computed tomography, and magnetic resonance imaging laboratories. How facilities involved in the accreditation process view accreditation is unknown. The objective of this study was to examine the perception of laboratory accreditation from those who had undergone the process. An electronic survey request was sent to all facilities that had received IAC accreditation at least once. Demographic information, as well as opinions on the perceived value of accreditation as it relates to 15 quality metrics was acquired. Responses were obtained from 2782 facilities. Of the 15 quality metrics examined, the process was perceived as leading to improvements by a majority of respondents for 10 (67%) metrics including: report standardization, adherence to guidelines, test standardization, report completeness, identification of deficiencies, improved staff knowledge, report timeliness, distinguished facility, correction of deficiencies, and image quality. Overall, the perceived improvement was greater for hospital-based facilities (global 66% vs 59%; P < 0.001). Survey data demonstrate that the accreditation process has a positive perceived impact on the majority of examined metrics. These findings suggest that those undergoing the process find value in accreditation.


Assuntos
Acreditação , Instituições de Assistência Ambulatorial/normas , Diagnóstico por Imagem/normas , Percepção , Qualidade da Assistência à Saúde , Humanos , Internet , Melhoria de Qualidade , Inquéritos e Questionários
18.
Eur Heart J ; 36(26): 1689-96, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25898845

RESUMO

AIMS: To characterize patient radiation doses from nuclear myocardial perfusion imaging (MPI) and the use of radiation-optimizing 'best practices' worldwide, and to evaluate the relationship between laboratory use of best practices and patient radiation dose. METHODS AND RESULTS: We conducted an observational cross-sectional study of protocols used for all 7911 MPI studies performed in 308 nuclear cardiology laboratories in 65 countries for a single week in March-April 2013. Eight 'best practices' relating to radiation exposure were identified a priori by an expert committee, and a radiation-related quality index (QI) devised indicating the number of best practices used by a laboratory. Patient radiation effective dose (ED) ranged between 0.8 and 35.6 mSv (median 10.0 mSv). Average laboratory ED ranged from 2.2 to 24.4 mSv (median 10.4 mSv); only 91 (30%) laboratories achieved the median ED ≤ 9 mSv recommended by guidelines. Laboratory QIs ranged from 2 to 8 (median 5). Both ED and QI differed significantly between laboratories, countries, and world regions. The lowest median ED (8.0 mSv), in Europe, coincided with high best-practice adherence (mean laboratory QI 6.2). The highest doses (median 12.1 mSv) and low QI (4.9) occurred in Latin America. In hierarchical regression modelling, patients undergoing MPI at laboratories following more 'best practices' had lower EDs. CONCLUSION: Marked worldwide variation exists in radiation safety practices pertaining to MPI, with targeted EDs currently achieved in a minority of laboratories. The significant relationship between best-practice implementation and lower doses indicates numerous opportunities to reduce radiation exposure from MPI globally.


Assuntos
Fidelidade a Diretrizes/normas , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Guias de Prática Clínica como Assunto/normas , Doses de Radiação , Exposição à Radiação/análise , Idoso , Cardiologia/normas , Protocolos Clínicos/normas , Estudos Transversais , Feminino , Saúde Global , Humanos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/normas , Tomografia por Emissão de Pósitrons/normas , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Prática Profissional/normas , Prática Profissional/estatística & dados numéricos , Qualidade da Assistência à Saúde/normas , Qualidade da Assistência à Saúde/estatística & dados numéricos , Análise de Regressão , Tomografia Computadorizada de Emissão de Fóton Único/normas , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos
19.
J Nucl Cardiol ; 22(3): 496-503, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25352528

RESUMO

BACKGROUND: The Medicare Improvements for Patients and Providers Act requires accreditation for all non-hospital suppliers of nuclear cardiology, nuclear medicine, and positron emission tomography (PET) studies as a condition of reimbursement. The perceptions of these facilities regarding the value and impact of the accreditation process are unknown. We conducted an electronic survey to assess the value of nuclear cardiology accreditation. METHODS: A request to participate in an electronic survey was sent to the medical and technical directors (n = 5,721) of all facilities who had received Intersocietal Accreditation Commission (IAC) Nuclear/PET accreditation. Demographic information, as well as, opinions on the value of accreditation as it relates to 16 quality metrics was obtained. RESULTS: There were 664 (11.6%) respondents familiar with the accreditation process of which 26% were hospital-based and 74% were nonhospital-based. Of the quality metrics examined, the process was perceived as leading to improvements by a majority of all respondents for 10 (59%) metrics including report standardization, report completeness, guideline adherence, deficiency identification, report timeliness, staff knowledge, facility distinction, deficiency correction, acquisition standardization, and image quality. Overall, the global perceived improvement was greater for hospital-based facilities (63% vs 57%; P < .001). Ninety-five percent of respondents felt that accreditation was important. Hospital-based facilities were more likely to feel that accreditation demonstrates a commitment to quality (43% vs 33%, P = .029), while nonhospital-based facilities were more likely to feel accreditation is important for reimbursement (50% vs 29%, P≤ .001). CONCLUSION: Although the accreditation process is demanding, the results of the IAC survey indicate that the accreditation process has a positive perceived impact for the majority of examined quality metrics, suggesting the facilities find the process to be valuable.


Assuntos
Cardiologia/organização & administração , Medicina Nuclear/organização & administração , Acreditação , Algoritmos , Atitude do Pessoal de Saúde , Cardiologia/métodos , Fidelidade a Diretrizes , Hospitais , Medicare , Medicina Nuclear/métodos , Tomografia por Emissão de Pósitrons , Melhoria de Qualidade , Qualidade da Assistência à Saúde , Inquéritos e Questionários , Estados Unidos
20.
J Am Coll Cardiol ; 63(15): 1480-9, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24530677

RESUMO

The current paper details the recommendations arising from an NIH-NHLBI/NCI-sponsored symposium held in November 2012, aiming to identify key components of a radiation accountability framework fostering patient-centered imaging and shared decision-making in cardiac imaging. Symposium participants, working in 3 tracks, identified key components of a framework to target critical radiation safety issues for the patient, the laboratory, and the larger population of patients with known or suspected cardiovascular disease. The use of ionizing radiation during an imaging procedure should be disclosed to all patients by the ordering provider at the time of ordering, and reinforced by the performing provider team. An imaging protocol with effective dose ≤3 mSv is considered very low risk, not warranting extensive discussion or written informed consent. However, a protocol effective dose >20 mSv was proposed as a level requiring particular attention in terms of shared decision-making and either formal discussion or written informed consent. Laboratory reporting of radiation dosimetry is a critical component of creating a quality laboratory fostering a patient-centered environment with transparent procedural methodology. Efforts should be directed to avoiding testing involving radiation, in patients with inappropriate indications. Standardized reporting and diagnostic reference levels for computed tomography and nuclear cardiology are important for the goal of public reporting of laboratory radiation dose levels in conjunction with diagnostic performance. The development of cardiac imaging technologies revolutionized cardiology practice by allowing routine, noninvasive assessment of myocardial perfusion and anatomy. It is now incumbent upon the imaging community to create an accountability framework to safely drive appropriate imaging utilization.


Assuntos
Cardiologia/métodos , Doenças Cardiovasculares/diagnóstico , Tomada de Decisões , Diagnóstico por Imagem/métodos , Assistência Centrada no Paciente/métodos , Lesões por Radiação/prevenção & controle , Humanos , Doses de Radiação , Radiação Ionizante
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