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1.
Am J Transplant ; 21(10): 3356-3368, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33742520

RESUMO

Premature cardiovascular disease and death with a functioning graft are leading causes of death and graft loss, respectively, in kidney transplant recipients (KTRs). Vascular stiffness and calcification are markers of cardiovascular disease that are prevalent in KTR and associated with subclinical vitamin K deficiency. We performed a single-center, phase II, parallel-group, randomized, double-blind, placebo-controlled trial (ISRCTN22012044) to test whether vitamin K supplementation reduced vascular stiffness (MRI-based aortic distensibility) or calcification (coronary artery calcium score on computed tomography) in KTR over 1 year of treatment. The primary outcome was between-group difference in vascular stiffness (ascending aortic distensibility). KTRs were recruited between September 2017 and June 2018, and randomized 1:1 to vitamin K (menadiol diphosphate 5 mg; n = 45) or placebo (n = 45) thrice weekly. Baseline demographics, clinical history, and immunosuppression regimens were similar between groups. There was no impact of vitamin K on vascular stiffness (treatment effect -0.23 [95% CI -0.75 to 0.29] × 10-3  mmHg-1 ; p = .377), vascular calcification (treatment effect -141 [95% CI - 320 to 38] units; p = .124), nor any other outcome measure. In this heterogeneous cohort of prevalent KTR, vitamin K supplementation did not reduce vascular stiffness or calcification over 1 year. Improving vascular health in KTR is likely to require a multifaceted approach.


Assuntos
Transplante de Rim , Calcificação Vascular , Rigidez Vascular , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Transplante de Rim/efeitos adversos , Calcificação Vascular/tratamento farmacológico , Vitamina K
2.
J Cardiovasc Magn Reson ; 23(1): 85, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34162405

RESUMO

BACKGROUND: Vascular calcification is an independent predictor of cardiovascular disease in patients with chronic kidney disease. Computed tomography (CT) is the gold-standard for detecting vascular calcification. Radial volumetric-interpolated breath-hold examination (radial-VIBE), a free-breathing gradient-echo cardiovascular magnetic resonance (CMR) sequence, has advantages over CT as it is ionising radiation-free. However, its capability in detecting thoracic aortic calcification (TAC) has not been investigated. This study aims to compare radial-VIBE to CT for the detection of TAC in the descending aorta of patients with end-stage renal disease (ESRD) using semi-automated methods, and to investigate the association between TAC and coronary artery calcification (CAC). METHODS: Paired cardiac CT and radial-VIBE CMR scans from ESRD patients participating in 2 prospective studies were obtained. Calcification volume was quantified using semi-automated methods in a 9 cm segment of the thoracic aorta. Correlation and agreement between TAC volume measured on CMR and CT were assessed with Spearman's correlation coefficient (ρ), linear regression, Bland-Altman plots and intraclass correlation coefficient (ICC). Association between CAC Agatston score and TAC volume determined by CT and CMR was measured with Spearman's correlation coefficient. RESULTS: Scans from 96 participants were analysed. Positive correlation was found between CMR and CT calcification volume [ρ = 0.61, 95% confidence interval (CI) 0.45-0.73]. ICC for consistency was 0.537 (95% CI 0.378-0.665). Bland-Altman plot revealed that compared to CT, CMR volumes were systematically higher at low calcification volume, and lower at high calcification volume. CT did not detect calcification in 41.7% of participants, while radial-VIBE CMR detected signal which the semi-quantitative algorithm reported as calcification in all of those individuals. Instances of suboptimal radial-VIBE CMR image quality were deemed to be the major contributors to the discrepancy. Correlations between CAC Agatston score and TAC volume measured by CT and CMR were ρ = 0.404 (95% CI 0.214-0.565) and ρ = 0.211 (95% CI 0.008-0.396), respectively. CONCLUSION: Radial-VIBE CMR can detect TAC with strong positive association to CT, albeit with the presence of proportional bias. Quantification of vascular calcification by radial-VIBE remains a promising area for future research, but improvements in image quality are necessary.


Assuntos
Doença da Artéria Coronariana , Falência Renal Crônica , Aorta Torácica/diagnóstico por imagem , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Estudos Prospectivos
3.
Radiology ; 293(3): 554-564, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31638489

RESUMO

Background Ferumoxytol is approved for use in the treatment of iron deficiency anemia, but it can serve as an alternative to gadolinium-based contrast agents. On the basis of postmarketing surveillance data, the Food and Drug Administration issued a black box warning regarding the risks of rare but serious acute hypersensitivity reactions during fast high-dose injection (510 mg iron in 17 seconds) for therapeutic use. Whereas single-center safety data for diagnostic use have been positive, multicenter data are lacking. Purpose To report multicenter safety data for off-label diagnostic ferumoxytol use. Materials and Methods The multicenter ferumoxytol MRI registry was established as an open-label nonrandomized surveillance databank without industry involvement. Each center monitored all ferumoxytol administrations, classified adverse events (AEs) using the National Cancer Institute Common Terminology Criteria for Adverse Events (grade 1-5), and assessed the relationship of AEs to ferumoxytol administration. AEs related to or possibly related to ferumoxytol injection were considered adverse reactions. The core laboratory adjudicated the AEs and classified them with the American College of Radiology (ACR) classification. Analysis of variance was used to compare vital signs. Results Between January 2003 and October 2018, 3215 patients (median age, 58 years; range, 1 day to 96 years; 1897 male patients) received 4240 ferumoxytol injections for MRI. Ferumoxytol dose ranged from 1 to 11 mg per kilogram of body weight (≤510 mg iron; rate ≤45 mg iron/sec). There were no systematic changes in vital signs after ferumoxytol administration (P > .05). No severe, life-threatening, or fatal AEs occurred. Eighty-three (1.9%) of 4240 AEs were related or possibly related to ferumoxytol infusions (75 mild [1.8%], eight moderate [0.2%]). Thirty-one AEs were classified as allergiclike reactions using ACR criteria but were consistent with minor infusion reactions observed with parenteral iron. Conclusion Diagnostic ferumoxytol use was well tolerated, associated with no serious adverse events, and implicated in few adverse reactions. Registry results indicate a positive safety profile for ferumoxytol use in MRI. © RSNA, 2019 Online supplemental material is available for this article.


Assuntos
Meios de Contraste/efeitos adversos , Óxido Ferroso-Férrico/efeitos adversos , Imageamento por Ressonância Magnética , Uso Off-Label , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Sistema de Registros
4.
J Magn Reson Imaging ; 41(5): 1268-71, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24903851

RESUMO

The emergence of an association between gadolinium-based contrast agents (GBCA) and the rare condition nephrogenic systemic fibrosis (NSF) led to a warning in 2006 from the Food and Drug Administration (FDA) restricting the use of the GBCAs to patients with an estimated glomerular filtration rate of >30 mL/min/1.73m(2) . We discuss our experience with a post-FDA restriction presentation of NSF and subsequent patient death in which the prolonged lead-time of ∼5.5 years led to challenges in ensuring a secure diagnosis of NSF and establishing risk exposures. Accurate contemporary records of contrast administration and clinical factors alongside clinical and pathological expertise ensured that we were able to confidently diagnose NSF, despite the length of lead time and confounding factors.


Assuntos
Aprovação de Drogas , Gadolínio DTPA/efeitos adversos , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/normas , Dermopatia Fibrosante Nefrogênica/diagnóstico , Guias de Prática Clínica como Assunto , Idoso , Meios de Contraste/efeitos adversos , Diagnóstico Diferencial , Gadolínio/efeitos adversos , Humanos , Masculino , Estados Unidos
5.
BMC Nephrol ; 15: 23, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24484613

RESUMO

BACKGROUND: Measurement of renal perfusion is a crucial part of measuring kidney function. Arterial spin labelling magnetic resonance imaging (ASL MRI) is a non-invasive method of measuring renal perfusion using magnetised blood as endogenous contrast. We studied the reproducibility of ASL MRI in normal volunteers. METHODS: ASL MRI was performed in healthy volunteers on 2 occasions using a 3.0 Tesla MRI scanner with flow-sensitive alternating inversion recovery (FAIR) perfusion preparation with a steady state free precession (True-FISP) pulse sequence. Kidney volume was measured from the scanned images. Routine serum and urine biochemistry were measured prior to MRI scanning. RESULTS: 12 volunteers were recruited yielding 24 kidneys, with a mean participant age of 44.1 ± 14.6 years, blood pressure of 136/82 mmHg and chronic kidney disease epidemiology formula estimated glomerular filtration rate (CKD EPI eGFR) of 98.3 ± 15.1 ml/min/1.73 m2. Mean kidney volumes measured using the ellipsoid formula and voxel count method were 123.5 ± 25.5 cm3, and 156.7 ± 28.9 cm3 respectively. Mean kidney perfusion was 229 ± 41 ml/min/100 g and mean cortical perfusion was 327 ± 63 ml/min/100 g, with no significant differences between ASL MRIs. Mean absolute kidney perfusion calculated from kidney volume measured during the scan was 373 ± 71 ml/min. Bland Altman plots were constructed of the cortical and whole kidney perfusion measurements made at ASL MRIs 1 and 2. These showed good agreement between measurements, with a random distribution of means plotted against differences observed. The intra class correlation for cortical perfusion was 0.85, whilst the within subject coefficient of variance was 9.2%. The intra class correlation for whole kidney perfusion was 0.86, whilst the within subject coefficient of variance was 7.1%. CONCLUSIONS: ASL MRI at 3.0 Tesla provides a repeatable method of measuring renal perfusion in healthy subjects without the need for administration of exogenous compounds. We have established normal values for renal perfusion using ASL MRI in a cohort of healthy volunteers.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Rim/fisiologia , Angiografia por Ressonância Magnética/métodos , Artéria Renal/fisiologia , Circulação Renal/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Rim/irrigação sanguínea , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Marcadores de Spin
6.
Open Heart ; 10(1)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36822817

RESUMO

BACKGROUND: We investigated the associations of healthcare worker status with multisystem illness trajectory in hospitalised post-COVID-19 individuals. METHODS AND RESULTS: One hundred and sixty-eight patients were evaluated 28-60 days after the last episode of hospital care. Thirty-six (21%) were healthcare workers. Compared with non-healthcare workers, healthcare workers were of similar age (51.3 (8.7) years vs 55.0 (12.4) years; p=0.09) more often women (26 (72%) vs 48 (38%); p<0.01) and had lower 10-year cardiovascular risk (%) (8.1 (7.9) vs 15.0 (11.5); p<0.01) and Coronavirus Clinical Characterisation Consortium in-hospital mortality risk (7.3 (10.2) vs 12.7 (9.8); p<0.01). Healthcare worker status associated with less acute inflammation (peak C reactive protein 48 mg/L (IQR: 14-165) vs 112 mg/L (52-181)), milder illness reflected by WHO clinical severity score distribution (p=0.04) and shorter duration of admission (4 days (IQR: 2-6) vs 6 days (3-12)).In adjusted multivariate logistic regression analysis, healthcare worker status associated with a binary classification (probable/very likely vs not present/unlikely) of adjudicated myocarditis (OR: 2.99; 95% CI (1.01 to 8.89) by 28-60 days postdischarge).After a mean (SD, range) duration of follow-up after hospital discharge of 450 (88) days (range 290, 627 days), fewer healthcare workers died or were rehospitalised (1 (3%) vs 22 (17%); p=0.038) and secondary care referrals for post-COVID-19 syndrome were common (42%) and similar to non-healthcare workers (38%; p=0.934). CONCLUSION: Healthcare worker status was independently associated with the likelihood of adjudicated myocarditis, despite better antecedent health. Two in five healthcare workers had a secondary care referral for post-COVID-19 syndrome. TRIAL REGISTRATION NUMBER: NCT04403607.


Assuntos
COVID-19 , Miocardite , Feminino , Humanos , Pessoa de Meia-Idade , Assistência ao Convalescente , COVID-19/complicações , COVID-19/diagnóstico , Miocardite/diagnóstico , Miocardite/epidemiologia , Alta do Paciente , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Pessoal de Saúde , Masculino , Adulto , Idoso
7.
Heart ; 108(21): e7, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-35613713

RESUMO

Heart and circulatory diseases affect more than seven million people in the UK. Non-invasive cardiac imaging is a critical element of contemporary cardiology practice. Progressive improvements in technology over the last 20 years have increased diagnostic accuracy in all modalities and led to the incorporation of non-invasive imaging into many standard cardiac clinical care pathways. Cardiac imaging tests are requested by a variety of healthcare practitioners and performed in a range of settings from the most advanced hospitals to local health centres. Imaging is used to detect the presence and consequences of cardiovascular disease, as well as to monitor the response to therapies. The previous UK national imaging strategy statement which brought together all of the non-invasive imaging modalities was published in 2010. The purpose of this document is to collate contemporary standards developed by the modality-specific professional organisations which make up the British Cardiovascular Society Imaging Council, bringing together common and essential recommendations. The development process has been inclusive and iterative. Imaging societies (representing both cardiology and radiology) reviewed and agreed on the initial structure. The final document therefore represents a position, which has been generated inclusively, presents rigorous standards, is applicable to clinical practice and deliverable. This document will be of value to a variety of healthcare professionals including imaging departments, the National Health Service or other organisations, regulatory bodies, commissioners and other purchasers of services, and service users, i.e., patients, and their relatives.


Assuntos
Cardiologia , Doenças Cardiovasculares , Doenças Cardiovasculares/diagnóstico por imagem , Diagnóstico por Imagem , Humanos , Sociedades , Medicina Estatal , Reino Unido
8.
Open Heart ; 8(1)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34031214

RESUMO

OBJECTIVE: To determine provision of MRI for patients with cardiac implantable electronic devices (CIEDs; pacemakers and defibrillators) in England, to understand regional variation and assess the impact of guideline changes. METHODS: Retrospective data related to MRI scans performed in patients with CIED over the preceding 12 months was collected using a structured survey tool distributed to every National Health Service Trust MRI unit in England. Data were compared with similar data from 2014/2015 and with demand (estimated from local CIED implantation rates and regional population data by sustainability and transformation partnerships (STPs)). RESULTS: Responses were received from 212 of 223 (95%) hospitals in England. 112 (53%) MRI units' scan patients with MR-conditional CIEDs (10% also scan non-MR conditional devices), compared with 46% of sites in 2014/2015. Total annual scan volume increased over fourfold between 2014 and 2019 (1090 to 4896 scans). There was widespread geographical variation, with five STPs (total population >3·5 million representing approximately 25 000 patients with CIED) with no local provision. There was no correlation between local demand (CIED implantation rates) and MRI provision (scan volume). Complication rates were extremely low with three events nationally in 12 months (0·06% CIED-MRI scans). CONCLUSIONS: Provision of MRI for patients with CIEDs in England increased over fourfold in 4 years, but an estimated 10-fold care gap remains. Almost half of hospitals and 1 in 10 STPs have no service, with no relationship between local supply and demand. Availability of MRI for patients with non-MR conditional devices, although demonstrably safe, remains limited.


Assuntos
Desfibriladores Implantáveis , Imageamento por Ressonância Magnética/métodos , Marca-Passo Artificial , Segurança do Paciente/normas , Inglaterra , Seguimentos , Humanos , Estudos Retrospectivos , Inquéritos e Questionários
9.
Open Heart ; 7(2)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33046593

RESUMO

AIM: A modified Delphi approach was used to develop consensus opinion among British Society for Cardiac Imaging/British Society of Cardiac CT (BSCI/BSCCT) members in order to prioritise research questions in cardiovascular imaging. METHODS: All members of the BSCI/BSCCT were invited to submit research questions that they considered to be of the highest clinical and/or academic priority in the field of cardiovascular imaging (phase 1). Subsequently a steering committee removed duplicate questions and combined questions of a similar theme by consensus agreement where appropriate. BSCI/BSCCT members were invited to rank the resulting research questions in two further iterative rounds (phases 2 and 3) to determine a final list of high-priority research questions. RESULTS: A total of 111 research questions were submitted in phase 1 by 30 BSCI/BSCCT members. While there was a broad range of topics, from determining the optimal features/markers of the vulnerable plaque to investigating how cardiac imaging can best be used to maximise clinical outcomes and economic costs, multimodality imaging-related (n=44, 40%) questions dominated the categories and coronary artery imaging (n=40, 36%) was the most common topic. Over two iterative rounds of prioritisation of these research questions, the original 111 were reduced to 75 questions in round 2, and 25 in round 3. From these 25 a final Top 10 list was distilled by consensus grouping. CONCLUSION: This study has identified and ranked the top research priorities in cardiovascular imaging, as identified by the BSCI/BSCCT membership. This is a first step towards identifying the cardiovascular imaging research priorities within the UK and may assist researchers and funding bodies alike in setting priorities.


Assuntos
Pesquisa Biomédica , Técnicas de Imagem Cardíaca , Doenças Cardiovasculares/diagnóstico por imagem , Projetos de Pesquisa , Doenças Cardiovasculares/terapia , Consenso , Técnica Delphi , Humanos , Valor Preditivo dos Testes , Prognóstico
10.
Radiology ; 251(2): 493-502, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19276319

RESUMO

PURPOSE: To find clinically relevant estimates of the accuracy of noninvasive imaging-Doppler ultrasonography (US), computed tomographic (CT) angiography, magnetic resonance (MR) angiography, and contrast material-enhanced MR angiography-in diagnosing both severe and moderate symptomatic carotid artery stenosis; to ascertain the effect of prespecified clinical factors and clinical setting on diagnostic accuracy; and to estimate the probability of agreement between two noninvasive tests. MATERIALS AND METHODS: Original principal investigators obtained ethics approval for each data set. All data were anonymized. Individual patient data sets (IPDs) for noninvasive imaging tests were used to determine sensitivity, specificity, and agreement between the tests for symptomatic carotid artery stenosis; to compare ipsilateral with contralateral arteries; to compare IPDs with literature estimates; to compare routine audit and research data; and to determine the effect of age and sex on sensitivity and specificity. RESULTS: Contrast-enhanced MR angiography was the most accurate (sensitivity, 0.85 [30 of 35]; 95% confidence interval [CI]: 0.69, 0.93; and specificity, 0.85 [67 of 78]; 95% CI: 0.76, 0.92) for 70%-99% symptomatic stenosis. Sensitivity for a 50%-69% stenosis was poor, although data were limited. Sensitivity and specificity were generally lower in the ipsilateral than in the contralateral artery. IPD estimates were lower than literature values. Results of comparison of research with audit-derived data were inconclusive. Neither age nor sex affected accuracy. Agreement was better between two Doppler US tests and between two contrast-enhanced MR angiographic tests than it was between Doppler US and contrast-enhanced MR angiography, except for a 70%-99% symptomatic stenosis. CONCLUSION: Primary studies should distinguish ipsilateral from contralateral arteries and carefully describe the patients' characteristics and study environment. The literature overestimates noninvasive imaging accuracy. More data are needed to inform physicians in routine clinical practice.


Assuntos
Angiografia/métodos , Estenose das Carótidas/diagnóstico , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
J Magn Reson Imaging ; 30(6): 1298-308, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19937930

RESUMO

Emerging evidence linking gadolinium-based contrast agents (GBCAs) to nephrogenic systemic fibrosis (NSF) has changed medical practice patterns toward forgoing GBCA-enhanced magnetic resonance imaging (MRI) or substituting other imaging methods, which are potentially less accurate and often radiation-based. This shift has been based on reports of high NSF incidence at sites where a confluence of risk factors occurred in patients with severe renal dysfunction. This review article explores the factors that affect NSF risk, compares risks of alternative imaging procedures, and demonstrates how risk can be managed by careful selection of GBCA dose, timing of injection with respect to dialysis, and other factors. Nearly half of NSF cases are a milder form that does not cause contractures or reduce mobility. It appears that eliminating even a single risk factor can reduce NSF incidence/risk at least 10-fold. Elimination of multiple risk factors by using single-dose GBCA, dialyzing dialysis patients quickly following GBCA administration, avoiding GBCA in acute renal failure while serum creatinine is rising, and avoiding nonionic linear GBCA in renal failure patients may reduce NSF risk more than a thousand-fold, thereby allowing safe GBCA-enhanced MRI in virtually all patients. J. Magn. Reson. Imaging 2009;30:1298-1308. (c) 2009 Wiley-Liss, Inc.


Assuntos
Gadolínio , Imageamento por Ressonância Magnética/estatística & dados numéricos , Dermopatia Fibrosante Nefrogênica/epidemiologia , Dermopatia Fibrosante Nefrogênica/prevenção & controle , Meios de Contraste , Humanos , Incidência , Medição de Risco , Fatores de Risco
12.
J Endovasc Ther ; 16 Suppl 1: I22-41, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19317577

RESUMO

The endovascular therapist now has many modern imaging techniques available to plan and execute treatment, whereas in the past vascular surgeons relied mostly on clinical examination and arteriography. Advances in computer technology have enabled fast acquisition and processing of the large amounts of digital data essential to capture the dynamic information from fast-flowing blood at high resolution. Functional imaging has begun to play a role in predicting stability of progressive vascular disease and the need for and risks of intervention. Computing power now affords the interventionist the ability to handle imaging data in powerful 3-dimensional programs and electronically "in-lay" a variety of devices to plan complex endovascular procedures from the familiar platform of a laptop. In four major clinical areas, carotid intervention, peripheral intervention, endoluminal grafting, and cardiac imaging, we review the latest advances and changes with an eye toward how we should best be using imaging in our patients undergoing endovascular treatment...now and into the future.


Assuntos
Angioplastia , Implante de Prótese Vascular , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/cirurgia , Técnicas de Diagnóstico Cardiovascular , Interpretação de Imagem Assistida por Computador , Aneurisma/diagnóstico , Aneurisma/cirurgia , Angiografia Digital , Angioplastia/instrumentação , Prótese Vascular , Implante de Prótese Vascular/instrumentação , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/cirurgia , Meios de Contraste , Cardiopatias/diagnóstico , Cardiopatias/cirurgia , Humanos , Angiografia por Ressonância Magnética , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/cirurgia , Valor Preditivo dos Testes , Radiografia Intervencionista , Stents , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler , Ultrassonografia de Intervenção
13.
J Vasc Interv Radiol ; 20(2): 165-72, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19081736

RESUMO

PURPOSE: To prospectively compare contrast-enhanced (CE) magnetic resonance (MR) angiography against digital subtraction angiography (DSA) in patients with critical lower-limb ischemia. MATERIALS AND METHODS: Thirty patients with critical lower limb ischemia underwent both CE MR angiography and DSA. CE MR angiography commenced with a dedicated high-resolution study of the below-knee arteries followed by a three-station bolus-chase examination. Two blinded observers recorded the severity of the most significant stenosis within each arterial segment. Interobserver agreement was calculated and, with DSA as the reference standard, the sensitivity and specificity of CE MR angiography for the detection of significant stenosis (>or=50% luminal narrowing) or occlusion was calculated. RESULTS: All 390 arterial segments were scored by both observers. Sensitivity was higher in the distal segments (92%-96%) compared with the proximal segments (69%-79%). Specificity was similar in distal (90%-91%) and more proximal segments (86%-96%). Overall, interobserver agreement was excellent (kappa = 0.95 for CE MR angiography and DSA) and was superior within the distal segments. Twenty-eight segments that were considered occluded on DSA were shown to be patent on CE MR angiography and 16 segments that were considered occluded on CE MR angiography were shown to be patent on DSA. CONCLUSIONS: In patients with critical lower-limb ischemia, CE MR angiography with high-resolution distal imaging is highly accurate for assessment of the below-knee arteries. Both DSA and CE MR angiography may identify patent vessels that are considered occluded based on the other modality.


Assuntos
Angiografia Digital/métodos , Gadolínio DTPA , Isquemia/diagnóstico , Perna (Membro)/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Perna (Membro)/diagnóstico por imagem , Perna (Membro)/patologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Br J Radiol ; 90(1069): 20160590, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27653560

RESUMO

There is growing evidence for the accumulation of gadolinium (Gd) in patients administered with intravenous Gd-based contrast agents, even in the absence of renal impairment. This review of the literature will discuss what has been found to date in cadaveric human studies, clinical studies of patients and from animal models. Evidence for the potential route of entry into the brain will be examined. The current state of knowledge of effects of Gd accumulation in the brain is discussed. We will then discuss what the possible implications may be for the choice of Gd-based contrast agents in clinical practice.


Assuntos
Encéfalo/efeitos dos fármacos , Meios de Contraste/farmacocinética , Gadolínio DTPA/farmacocinética , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Animais , Gadolínio DTPA/administração & dosagem , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Neuroimagem/efeitos adversos , Neuroimagem/métodos , Segurança do Paciente , Medição de Risco
15.
Nephron ; 133(3): 183-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27362585

RESUMO

AIMS: Arterial spin labelling (ASL) MRI measures perfusion without administration of contrast agent. While ASL has been validated in animals and healthy volunteers (HVs), application to chronic kidney disease (CKD) has been limited. We investigated the utility of ASL MRI in patients with CKD. METHODS: We studied renal perfusion in 24 HVs and 17 patients with CKD (age 22-77 years, 40% male) using ASL MRI at 3.0T. Kidney function was determined using estimated glomerular filtration rate (eGFR). T1 relaxation time was measured using modified look-locker inversion and xFB02;ow-sensitive alternating inversion recovery true-fast imaging and steady precession was performed to measure cortical and whole kidney perfusion. RESULTS: T1 was higher in CKD within cortex and whole kidney, and there was association between T1 time and eGFR. No association was seen between kidney size and volume and either T1, or ASL perfusion. Perfusion was lower in CKD in cortex (136 ± 37 vs. 279 ± 69 ml/min/100 g; p < 0.001) and whole kidney (146 ± 24 vs. 221 ± 38 ml/min/100 g; p < 0.001). There was significant, negative, association between T1 longitudinal relaxation time and ASL perfusion in both the cortex (r = -0.75, p < 0.001) and whole kidney (r = -0.50, p < 0.001). There was correlation between eGFR and both cortical (r = 0.73, p < 0.01) and whole kidney (r = 0.69, p < 0.01) perfusion. CONCLUSIONS: Significant differences in renal structure and function were demonstrated using ASL MRI. T1 may be representative of structural changes associated with CKD; however, further investigation is required into the pathological correlates of reduced ASL perfusion and increased T1 time in CKD.


Assuntos
Córtex Renal/diagnóstico por imagem , Falência Renal Crônica/diagnóstico por imagem , Medula Renal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Córtex Renal/fisiologia , Córtex Renal/fisiopatologia , Medula Renal/fisiologia , Medula Renal/fisiopatologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Insights Imaging ; 3(5): 495-504, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22865510

RESUMO

OBJECTIVES: This review aims to establish the impact on conventional angiography and endovascular intervention of contrast-enhanced magnetic resonance angiography (CE-MRA) and contrast-enhanced computed tomography angiography (CE-CTA) on a background of evolving technology, changing clinical requirements and resulting clinical repercussions. METHODS: The angiographic and interventional caseload was prospectively recorded between 1997 and 2010, along with the CE-MRA and CE-CTA caseload. Waiting times and the marginal cost analyses for 2001 and 2009 were also prospectively established. RESULTS: Conventional diagnostic angiographies declined from a peak of 847 to 121 per year while endovascular interventions continue in similar numbers. CE-MRA increased from effectively none initially to 620 per year while CE-CTA has currently risen to 396 per year. Total diagnostic study numbers have increased but at reduced cost. Various influences are clear, including on-site modality availability, capability and accuracy along with impact of new therapies, research studies and adverse events. CONCLUSIONS: Vascular imaging has undergone a metamorphosis in little over a decade because of CE-MRA and CE-CTA. With waiting times significantly reduced since the start of the study and the cost-effectiveness of both CE-MRA and CE-CTA as primary diagnostic investigations established, further development of these services is inevitable. MAIN MESSAGES: • The availability of CE-MRA and CE-CTA has reduced the need for conventional angiography. • Both waiting times and the marginal cost analyses for CE-MRA and CE-CTA have reduced. • The impact of new therapies, research studies (e.g. ASTRAL) and adverse events is illustrated.

18.
JACC Cardiovasc Imaging ; 4(11): 1206-16, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22093272

RESUMO

Discovery of an association between gadolinium-based contrast agents (GBCAs) and nephrogenic systemic fibrosis (NSF) has led to less use of GBCA-enhanced magnetic resonance imaging in dialysis patients and patients with severe renal failure at risk of NSF, and the virtual elimination of new cases of NSF. But shifting patients with renal failure to alternative imaging methods may subject patients to other risks (e.g., ionizing radiation or iodinated contrast). This review paper examines 370 NSF cases reported in 98 articles to analyze NSF risk factors. Eliminating multiple risk factors by limiting GBCA dose to a maximum of 0.1 mmol/kg, dialyzing patients undergoing dialysis quickly following GBCA administration, delaying GBCA in acute renal failure until after renal function returns or dialysis is initiated, and avoiding nonionic linear GBCA in patients with renal failure especially when there are proinflammatory conditions may substantially reduce the risk of NSF.


Assuntos
Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Dermopatia Fibrosante Nefrogênica/patologia , Insuficiência Renal/complicações , Pele/patologia , Biópsia , Relação Dose-Resposta a Droga , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Imageamento por Ressonância Magnética , Dermopatia Fibrosante Nefrogênica/etiologia , Dermopatia Fibrosante Nefrogênica/fisiopatologia , Dermopatia Fibrosante Nefrogênica/prevenção & controle , Seleção de Pacientes , Diálise Renal , Insuficiência Renal/fisiopatologia , Insuficiência Renal/terapia , Medição de Risco , Fatores de Risco
19.
J Cardiovasc Comput Tomogr ; 2(5): 332-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19083972

RESUMO

Current clinical practice dictates that invasive management strategies frequently are adopted in patients with both ST-segment elevation and non-ST-segment elevation acute coronary syndromes. Such strategies rely on obtaining vascular access and, as such, are not always technically feasible. We report a case in which cardiac computed tomography was used to great effect in the diagnostic and (targeted) interventional management of a patient who was the recipient of a previous coronary artery bypass grafting and presented with global myocardial ischemia, in whom the lack of peripheral pulses had previously rendered an early invasive strategy hazardous.


Assuntos
Aterosclerose/cirurgia , Síndrome do Roubo Subclávio/cirurgia , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Humanos , Masculino , Radiografia Intervencionista/métodos
20.
J Endovasc Ther ; 11 Suppl 2: II163-79, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15760254

RESUMO

Vascular imaging techniques, such as catheter angiography, ultrasound, computed tomography (CT), and magnetic resonance (MR), have all undergone unprecedented innovation and incredible technological leaps in the last 10 years. Ultrasound, CT, and MR have progressed in acquisition speed, resolution, and accuracy to the point that they have now supplanted the former mainstay, invasive catheter-based angiography, despite the advent of digitized angiographic image recording. This review explores the advantages and shortcomings of each technique and how they have changed the diagnosis and assessment of the cardiovascular system for endovascular intervention.


Assuntos
Doenças Cardiovasculares/diagnóstico , Diagnóstico por Imagem , Doenças Cardiovasculares/diagnóstico por imagem , Diagnóstico por Imagem/tendências , Ecocardiografia Transesofagiana , Humanos , Imageamento por Ressonância Magnética , Doses de Radiação , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção
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