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1.
BMJ Open ; 12(10): e063594, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36270757

RESUMO

PURPOSE: Risk factor-based models struggle to accurately predict the development of cardiovascular disease (CVD) at the level of the individual. Ways of identifying people with low predicted risk who will develop CVD would allow stratified advice and support informed treatment decisions about the initiation or adjustment of preventive medication, and this is the aim of this prospective cohort study. PARTICIPANTS: The Tayside Screening for Cardiac Events (TASCFORCE) study recruited men and women aged≥40 years, free from known CVD, with a predicted 10-year risk of coronary heart disease<20%. If B-type natriuretic peptide (BNP) was greater than their gender median, participants were offered a whole-body contrast-enhanced MRI (WBCE-MRI) scan (cardiac imaging, whole-body angiography to determine left ventricular parameters, delayed gadolinium enhancement, atheroma burden). Blood, including DNA, was stored for future biomarker assays. Participants are being followed up using electronic record-linkage cardiovascular outcomes. FINDINGS TO DATE: 4423 (1740, 39.3% men) were recruited. Mean age was 52.3 years with a median BNP of 7.50 ng/L and 15.30 ng/L for men and women, respectively. 602 had a predicted 10-year risk of 10%-19.9%, with the remainder<10%. Age, female sex, ex-smoking status, lower heart rate, higher high-density lipoprotein and lower total cholesterol were independently associated with higher log10 BNP levels. Mean left ventricular mass was 129.2 g and 87.0 g in men and women, respectively. FUTURE PLANS: The TASCFORCE study is investigating the ability of a screening programme, using BNP and WBCE-MRI, at the time of enrolment, to evaluate prediction of CVD in a population at low/intermediate risk. Blood stored for future biomarker analyses will allow testing/development of novel biomarkers. We believe this could be a new UK Framingham study allowing study for many years to come. CLINICAL TRIAL REGISTRATION: ISRCTN38976321.


Assuntos
Doenças Cardiovasculares , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Peptídeo Natriurético Encefálico , Gadolínio , Meios de Contraste , Fatores de Risco , Fatores de Risco de Doenças Cardíacas , Biomarcadores , Colesterol , Lipoproteínas HDL
2.
Lancet Oncol ; 23(4): 501-513, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35279270

RESUMO

BACKGROUND: Early diagnosis of malignant spinal cord compression (SCC) is crucial because pretreatment neurological status is the major determinant of outcome. In metastatic castration-resistant prostate cancer, SCC is a clinically significant cause of disease-related morbidity and mortality. We investigated whether screening for SCC with spinal MRI, and pre-emptive treatment if radiological SCC (rSCC) was detected, reduced the incidence of clinical SCC (cSCC) in asymptomatic patients with metastatic castration-resistant prostate cancer and spinal metastasis. METHODS: We did a parallel-group, open-label, randomised, controlled, phase 3, superiority trial. Patients with metastatic castration-resistant prostate cancer were recruited from 45 National Health Service hospitals in the UK. Eligible patients were aged at least 18 years, with an Eastern Co-operative Oncology Group performance status of 0-2, asymptomatic spinal metastasis, no previous SCC, and no spinal MRI in the past 12 months. Participants were randomly assigned (1:1), using a minimisation algorithm with a random element (balancing factors were treatment centre, alkaline phosphatase [normal vs raised, with the upper limit of normal being defined at each participating laboratory], number of previous systemic treatments [first-line vs second-line or later], previous spinal treatment, and imaging of thorax and abdomen), to no MRI (control group) or screening spinal MRI (intervention group). Serious adverse events were monitored in the 24 h after screening MRI in the intervention group. Participants with screen-detected rSCC were offered pre-emptive treatment (radiotherapy or surgical decompression was recommended per treating physician's recommendation) and 6-monthly spinal MRI. All patients were followed up every 3 months, and then at month 30 and 36. The primary endpoint was time to and incidence of confirmed cSCC in the intention-to-treat population (defined as all patients randomly assigned), with the primary timepoint of interest being 1 year after randomisation. The study is registered with ISRCTN, ISRCTN74112318, and is now complete. FINDINGS: Between Feb 26, 2013, and April 25, 2017, 420 patients were randomly assigned to the control (n=210) or screening MRI (n=210) groups. Median age was 74 years (IQR 68 to 79), 222 (53%) of 420 patients had normal alkaline phosphatase, and median prostate-specific antigen concentration was 48 ng/mL (IQR 17 to 162). Screening MRI detected rSCC in 61 (31%) of 200 patients with assessable scans in the intervention group. As of data cutoff (April 23, 2020), at a median follow-up of 22 months (IQR 13 to 31), time to cSCC was not significantly improved with screening (hazard ratio 0·64 [95% CI 0·37 to 1·11]; Gray's test p=0·12). 1-year cSCC rates were 6·7% (95% CI 3·8-10·6; 14 of 210 patients) for the control group and 4·3% (2·1-7·7; nine of 210 patients) for the intervention group (difference -2·4% [95% CI -4·2 to 0·1]). Median time to cSCC was not reached in either group. No serious adverse events were reported within 24 h of screening. INTERPRETATION: Despite the substantial incidence of rSCC detected in the intervention group, the rate of cSCC in both groups was low at a median of 22 months of follow-up. Routine use of screening MRI and pre-emptive treatment to prevent cSCC is not warranted in patients with asymptomatic castration-resistant prostate cancer with spinal metastasis. FUNDING: Cancer Research UK.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Compressão da Medula Espinal , Neoplasias da Coluna Vertebral , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Detecção Precoce de Câncer , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/etiologia , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Medicina Estatal , Reino Unido/epidemiologia
3.
Int J Chron Obstruct Pulmon Dis ; 15: 2015-2024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32904701

RESUMO

Background: Oxidative stress (OS) has been implicated in the development of pulmonary hypertension (PH) and ventricular hypertrophy. Xanthine oxidase is a well-recognised source of reactive oxygen species, which lead to OS. The aim of this proof of concept study was to assess whether allopurinol (xanthine oxidase inhibitor) would reduce right ventricular mass (RVM) in patients with PH-associated chronic lung disease (PH-CLD). Methods: We conducted a randomised, double-blind, parallel-group, placebo-controlled trial in patients with PH-CLD (93% COPD, 7% IPF) who were randomly assigned to receive allopurinol or placebo for 12 months. The primary outcome was the mean change in RVM, as assessed by cardiac magnetic resonance imaging (CMRI). Secondary outcomes included quality of life (QOL), spirometry and six-minute walk test (6MWT). Results: Seventy-one patients were recruited: mean age 71 years, mean pulmonary arterial pressure 30 mm Hg, FEV1 60% and resting SpO2 96%. After 12 months, there was no significant difference in the change in RVM from baseline (allopurinol 1.85g vs placebo 0.97g with mean difference 0.88g, CI -4.77 to 3.01, p =0.7). There were also no significant changes in other cardiac parameters measured on MRI, in QOL, spirometry and 6MWT. Subgroup analysis showed that allopurinol significantly reduced RVM compared to placebo with -6.16g vs 0.75g and mean difference 6.92g (CI 1.14 to 12.69, p = 0.02) in COPD patients with more severe airflow limitation. Conclusion: Allopurinol had no overall impact on patients with PH-CLD but had potential benefit in COPD patients with more severe airflow limitation.


Assuntos
Hipertensão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Idoso , Alopurinol/efeitos adversos , Método Duplo-Cego , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Qualidade de Vida , Teste de Caminhada
4.
Radiology ; 287(3): 795-804, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29714681

RESUMO

Purpose To quantify the burden and distribution of asymptomatic atherosclerosis in a population with a low to intermediate risk of cardiovascular disease. Materials and Methods Between June 2008 and February 2013, 1528 participants with 10-year risk of cardiovascular disease less than 20% were prospectively enrolled. They underwent whole-body magnetic resonance (MR) angiography at 3.0 T by using a two-injection, four-station acquisition technique. Thirty-one arterial segments were scored according to maximum stenosis. Scores were summed and normalized for the number of assessable arterial segments to provide a standardized atheroma score (SAS). Multiple linear regression was performed to assess effects of risk factors on atheroma burden. Results A total of 1513 participants (577 [37.9%] men; median age, 53.5 years; range, 40-83 years) completed the study protocol. Among 46 903 potentially analyzable segments, 46 601 (99.4%) were interpretable. Among these, 2468 segments (5%) demonstrated stenoses, of which 1649 (3.5%) showed stenosis less than 50% and 484 (1.0%) showed stenosis greater than or equal to 50%. Vascular stenoses were distributed throughout the body with no localized distribution. Seven hundred forty-seven (49.4%) participants had at least one stenotic vessel, and 408 (27.0%) participants had multiple stenotic vessels. At multivariable linear regression, SAS correlated with age (B = 3.4; 95% confidence interval: 2.61, 4.20), heart rate (B = 1.23; 95% confidence interval: 0.51, 1.95), systolic blood pressure (B = 0.02; 95% confidence interval: 0.01, 0.03), smoking status (B = 0.79; 95% confidence interval: 0.44, 1.15), and socioeconomic status (B = -0.06; 95% confidence interval: -0.10, -0.02) (P < .01 for all). Conclusion Whole-body MR angiography identifies early vascular disease at a population level. Although disease prevalence is low on a per-vessel level, vascular disease is common on a per-participant level, even in this low- to intermediate-risk cohort. © RSNA, 2018 Online supplemental material is available for this article.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Angiografia por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Risco , Escócia/epidemiologia
6.
Eur Radiol ; 27(1): 315-324, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27053260

RESUMO

OBJECTIVES: Left ventricular mass (LVM) at cardiac magnetic resonance imaging (CMR) is a frequent end point in clinical trials in nephrology. Trial participants with end stage renal disease (ESRD) may have a greater frequency of incidental findings (IF). We retrospectively investigated prevalence of IF in previous research CMR and reviewed their subsequent impact on participants. METHODS: Between 2002 and 2006, 161 ESRD patients underwent CMR in a transplant assessment study. Images were used to assess LV mass and function. In the current study a radiologist reviewed the scans for IF. Review of patient records determined the subsequent clinical significance of IF. RESULTS: There were 150 IF in 95 study participants. Eighty-four (56 %) were new diagnoses. One hundred and two were non-cardiac. Fifteen were suspicious of malignancy. There was a clinically significant IF for 14.9 % of the participants. In six cases earlier identification of an IF may have improved quality of life or survival. CONCLUSIONS: Without radiology support clinically important IF may be missed on CMR. Patients undergoing CMR in trials should be counselled about the frequency and implications of IF. Patients with ESRD have a higher prevalence of IF than reported in other populations. Nephrology studies require mechanisms for radiologist reporting and strategies for dealing with IF. KEY POINTS: • Incidental findings on research cardiac magnetic resonance imaging can have significant consequences. • We considered incidental findings in historical renal cardiac resonance imaging clinical trials. • Incidental findings are common and important in the chronic kidney disease population. • Without radiology support, clinically significant incidental findings may be missed on imaging. • Study protocols, approvals and consent processes should take account of possible findings.


Assuntos
Cardiopatias/complicações , Cardiopatias/diagnóstico por imagem , Achados Incidentais , Falência Renal Crônica/complicações , Falência Renal Crônica/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Coração/diagnóstico por imagem , Cardiopatias/patologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Prevalência , Estudos Retrospectivos
7.
Minim Invasive Ther Allied Technol ; 26(1): 31-38, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27564687

RESUMO

This study presents a framework for workflow optimisation of multimodal image-guided procedures (MIGP) based on discrete event simulation (DES). A case of a combined X-Ray and magnetic resonance image-guided transarterial chemoembolisation (TACE) is presented to illustrate the application of this method. We used a ranking and selection optimisation algorithm to measure the performance of a number of proposed alternatives to improve a current scenario. A DES model was implemented with detail data collected from 59 TACE procedures and durations of magnetic resonance imaging (MRI) diagnostic procedures usually performed in a common MRI suite. Fourteen alternatives were proposed and assessed to minimise the waiting times and improve workflow. Data analysis observed an average of 20.68 (7.68) min of waiting between angiography and MRI for TACE patients in 71.19% of the cases. Following the optimisation analysis, an alternative was identified to reduce waiting times in angiography suite up to 48.74%. The model helped to understand and detect 'bottlenecks' during multimodal TACE procedures, identifying a better alternative to the current workflow and reducing waiting times. Simulation-based workflow analysis provides a cost-effective way to face some of the challenges of introducing MIGP in clinical radiology, highligthed in this study.


Assuntos
Quimioembolização Terapêutica/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Imagem Multimodal/métodos , Radiografia Intervencionista/métodos , Fluxo de Trabalho , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Fatores de Tempo
8.
J Magn Reson Imaging ; 44(5): 1186-1196, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27143317

RESUMO

PURPOSE: To scan a volunteer population using 3.0T magnetic resonance imaging (MRI). MRI of the left ventricular (LV) structure and function in healthy volunteers has been reported extensively at 1.5T. MATERIALS AND METHODS: A population of 1528 volunteers was scanned. A standardized approach was taken to acquire steady-state free precession (SSFP) LV data in the short-axis plane, and images were quantified using commercial software. Six observers undertook the segmentation analysis. RESULTS: Mean values (±standard deviation, SD) were: ejection fraction (EF) = 69 ± 6%, end diastolic volume index (EDVI) = 71 ± 13 ml/m2 , end systolic volume index (ESVI) = 22 ± 7 ml/m2 , stroke volume index (SVI) = 49 ± 8 ml/m2 , and LV mass index (LVMI) = 55 ± 12 g/m2 . The mean EF was slightly larger for females (69%) than for males (68%), but all other variables were smaller for females (EDVI 68v77 ml/m2 , ESVI 21v25 ml/m2 , SVI 46v52 ml/m2 , LVMI 49v64 g/m2 , all P < 0.05). The mean LV volume data mostly decreased with each age decade (EDVI males: -2.9 ± 1.3 ml/m2 , females: -3.1 ± 0.8 ml/m2 ; ESVI males: -1.3 ± 0.7 ml/m2 , females: -1.7 ± 0.5 ml/m2 ; SVI males: -1.7 ± 0.9 ml/m2 , females: -1.4 ± 0.6 ml/m2 ; LVMI males: -1.6 ± 1.1 g/m2 , females: -0.2 ± 0.6 g/m2 ) but the mean EF was virtually stable in males (0.6 ± 0.6%) and rose slightly in females (1.2 ± 0.5%) with age. CONCLUSION: LV reference ranges are provided in this population-based MR study at 3.0T. The variables are similar to those described at 1.5T, including variations with age and gender. These data may help to support future population-based MR research studies that involve the use of 3.0T MRI scanners. J. Magn. Reson. Imaging 2016;44:1186-1196.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Ventrículos do Coração/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Valores de Referência , Distribuição por Sexo , Fatores Sexuais , Reino Unido/epidemiologia
9.
BMC Med Imaging ; 16: 18, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26923316

RESUMO

BACKGROUND: The aim of this study was to use whole body cardiovascular magnetic resonance imaging (WB CVMR) to assess the heart and arterial network in a single examination, so as to describe the burden of atherosclerosis and subclinical disease in participants with symptomatic single site vascular disease. METHODS: 64 patients with a history of symptomatic single site vascular disease (38 coronary artery disease (CAD), 9 cerebrovascular disease, 17 peripheral arterial disease (PAD)) underwent whole body angiogram and cardiac MR in a 3 T scanner. The arterial tree was subdivided into 31 segments and each scored according to the degree of stenosis. From this a standardised atheroma score (SAS) was calculated. Cine and late gadolinium enhancement images of the left ventricle were obtained. RESULTS: Asymptomatic atherosclerotic disease with greater than 50% stenosis in arteries other than that responsible for their presenting complain was detected in 37% of CAD, 33% of cerebrovascular and 47% of PAD patients. Unrecognised myocardial infarcts were observed in 29% of PAD patients. SAS was significantly higher in PAD patients 24 (17.5-30.5) compared to CAD 4 (2-11.25) or cerebrovascular disease patients 6 (2-10) (ANCOVA p < 0.001). Standardised atheroma score positively correlated with age (ß 0.36 p = 0.002), smoking status (ß 0.34 p = 0.002), and LV mass (ß -0.61 p = 0.001) on multiple linear regression. CONCLUSION: WB CVMR is an effective method for the stratification of cardiovascular disease. The high prevalence of asymptomatic arterial disease, and silent myocardial infarctions, particularly in the peripheral arterial disease group, demonstrates the importance of a systematic approach to the assessment of cardiovascular disease.


Assuntos
Aterosclerose/diagnóstico , Doenças Cardiovasculares/complicações , Imageamento por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Fatores Etários , Idoso , Aterosclerose/epidemiologia , Doenças Cardiovasculares/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco
10.
Ann Vasc Surg ; 32: 1-4, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26806240

RESUMO

BACKGROUND: The fistula first initiative has promoted arteriovenous fistulas (AVFs) as the vascular access of choice. To preserve as many future access options as possible, multiple guidelines advocate that the most distal AVF possible should be created in the first place. Generally, snuff box and radiocephalic (RC) are accepted and well-described sites for AVFs; however, the forearm ulnar-basilic (UB) AVF is seldom used or recommended. The aim of this study is to assess and systematically review the evidence base for the creation of the UB fistula and to critically appraise whether more attention should be given to this site. METHODS: Electronic databases were searched for studies involving the creation of UB fistulas for dialysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary outcomes for this study were 1-year primary and secondary patency rates. Secondary outcomes were rates of hemodialysis access-induced distal ischemia (HAIDI) and infection. RESULTS: After strict inclusion and/or exclusion criteria by 2 reviewers, 8 studies were included in our review. Weighted-pooled data reveal 1-year primary patency rate for UB AVFs of 53.0% (95% confidence interval [CI]: 40.1-65.8%) with a secondary patency rate of 72.0% (95% CI: 59.2-83.3). HAIDI and infection rates were low. CONCLUSIONS: Our review has shown that the UB AVF may be a viable alternative when a RC AVF is not possible, and dialysis is not required urgently. It has adequate 1-year primary and secondary patency rates and extremely low risk of HAIDI. While it may be more challenging for both surgeons and dialysis nurses to make it a successful vascular access it offers a further option of distal access which may be overlooked.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Diálise Renal , Insuficiência Renal Crônica/terapia , Artéria Ulnar/cirurgia , Extremidade Superior/irrigação sanguínea , Veias/cirurgia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Humanos , Isquemia/etiologia , Insuficiência Renal Crônica/diagnóstico , Infecção da Ferida Cirúrgica/etiologia , Resultado do Tratamento , Artéria Ulnar/fisiopatologia , Grau de Desobstrução Vascular , Veias/fisiopatologia
11.
J Vasc Access ; 17(1): 40-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26349875

RESUMO

PURPOSE: Haemodialysis access-induced distal ischaemia (HAIDI) is a significant complication of vascular access creation, and has traditionally been difficult to manage without loss of access. Current treatment options include ligation, banding, distal revascularisation with interval ligation (DRIL), proximalisation of the arterial inflow (PAI) and revision using distal flow (RUDI). The purpose of this review was to evaluate the effectiveness of the different surgical techniques in the treatment of HAIDI. METHODS: Electronic databases were searched for studies assessing surgical techniques in the treatment of HAIDI in accordance with PRISMA. The primary outcome for the study was symptomatic relief for each technique, defined within each study. Secondary outcomes included comparison of early thrombosis rates following each different procedure. RESULTS: Following strict inclusion/exclusion criteria by two reviewers, twenty-seven studies of surgical interventions were included and divided into subgroups for banding, DRIL, PAI and RUDI procedures. Both DRIL and banding procedures were found to have high rates of symptomatic relief. In addition, the DRIL has a significantly lower rate of early thrombosis than banding although the more recent papers seem to suggest that early thrombosis is less of a problem in banding. PAI and RUDI showed some promise but there were too few studies to be able to make any clear conclusions. CONCLUSIONS: All four procedures have high success rate in relieving ischaemic symptoms with the DRIL procedure having a significantly better vascular access patency rate than other techniques, although further well designed studies are required to compare all four surgical techniques.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares , Oclusão de Enxerto Vascular/cirurgia , Isquemia/cirurgia , Diálise Renal , Procedimentos Endovasculares/efeitos adversos , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Isquemia/diagnóstico , Isquemia/etiologia , Isquemia/fisiopatologia , Ligadura , Fluxo Sanguíneo Regional , Reoperação , Fatores de Risco , Resultado do Tratamento , Grau de Desobstrução Vascular
12.
Int J Comput Assist Radiol Surg ; 10(10): 1639-50, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25700699

RESUMO

PURPOSE: A methodological framework is introduced to assess and compare a conventional fluoroscopy protocol for peripheral angioplasty with a new magnetic resonant imaging (MRI)-guided protocol. Different scenarios were considered during interventions on a perfused arterial phantom with regard to time-based and cognitive task analysis, user experience and ergonomics. METHODS: Three clinicians with different expertise performed a total of 43 simulated common iliac angioplasties (9 fluoroscopic, 34 MRI-guided) in two blocks of sessions. Six different configurations for MRI guidance were tested in the first block. Four of them were evaluated in the second block and compared to the fluoroscopy protocol. Relevant stages' durations were collected, and interventions were audio-visually recorded from different perspectives. A cued retrospective protocol analysis (CRPA) was undertaken, including personal interviews. In addition, ergonomic constraints in the MRI suite were evaluated. RESULTS: Significant differences were found when comparing the performance between MRI configurations versus fluoroscopy. Two configurations [with times of 8.56 (0.64) and 9.48 (1.13) min] led to reduce procedure time for MRI guidance, comparable to fluoroscopy [8.49 (0.75) min]. The CRPA pointed out the main influential factors for clinical procedure performance. The ergonomic analysis quantified musculoskeletal risks for interventional radiologists when utilising MRI. Several alternatives were suggested to prevent potential low-back injuries. CONCLUSIONS: This work presents a step towards the implementation of efficient operational protocols for MRI-guided procedures based on an integral and multidisciplinary framework, applicable to the assessment of current vascular protocols. The use of first-user perspective raises the possibility of establishing new forms of clinical training and education.


Assuntos
Angioplastia/métodos , Fluoroscopia/métodos , Aneurisma Ilíaco/cirurgia , Imageamento por Ressonância Magnética/métodos , Cirurgia Assistida por Computador/métodos , Simulação por Computador , Ergonomia , Humanos , Estudos Retrospectivos , Fluxo de Trabalho
13.
Int J Comput Assist Radiol Surg ; 10(5): 637-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25102933

RESUMO

PURPOSE: Interventional MRI has significant potential for image guidance of iliac angioplasty and related vascular procedures. A technology framework with in-room image display, control, communication and MRI-guided intervention techniques was designed and tested for its potential to provide safe, fast and efficient MRI-guided angioplasty of the iliac arteries. METHODS: A 1.5-T MRI scanner was adapted for interactive imaging during endovascular procedures using new or modified interventional devices such as guidewires and catheters. A perfused vascular phantom was used for testing. Pre-, intra- and post-procedural visualization and measurement of vascular morphology and flow was implemented. A detailed analysis of X-ray fluoroscopic angiography workflow was conducted and applied. Two interventional radiologists and one physician in training performed 39 procedures. All procedures were timed and analyzed. RESULTS: MRI-guided iliac angioplasty procedures were successfully performed with progressive adaptation of techniques and workflow. The workflow, setup and protocol enabled a reduction in table time for a dedicated MRI-guided procedure to 6 min 33 s with a mean procedure time of 9 min 2 s, comparable to the mean procedure time of 8 min 42 s for the standard X-ray-guided procedure. CONCLUSIONS: MRI-guided iliac vascular interventions were found to be feasible and practical using this framework and optimized workflow. In particular, the real-time flow analysis was found to be helpful for pre- and post-interventional assessments. Design optimization of the catheters and in vivo experiments are required before clinical evaluation.


Assuntos
Angioplastia/métodos , Artéria Ilíaca/cirurgia , Imagem por Ressonância Magnética Intervencionista/métodos , Estudos de Viabilidade , Angiofluoresceinografia , Humanos , Artéria Ilíaca/patologia
14.
J Am Coll Cardiol ; 61(9): 926-32, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23449426

RESUMO

OBJECTIVES: This study sought to ascertain if high-dose allopurinol regresses left ventricular mass (LVM) in patients with ischemic heart disease (IHD). BACKGROUND: LV hypertrophy (LVH) is common in patients with IHD including normotensive patients. Allopurinol, a xanthine oxidase inhibitor, has been shown to reduce LV afterload in IHD and may therefore also regress LVH. METHODS: A randomized, double-blind, placebo-controlled, parallel group study was conducted in 66 patients with IHD and LVH, comparing 600 mg/day allopurinol versus placebo therapy for 9 months. The primary outcome measure was change in LVM, assessed by cardiac magnetic resonance imaging (CMR). Secondary outcome measures were changes in LV volumes by CMR, changes in endothelial function by flow-mediated dilation (FMD), and arterial stiffness by applanation tonometry. RESULTS: Compared to placebo, allopurinol significantly reduced LVM (allopurinol -5.2 ± 5.8 g vs. placebo -1.3 ± 4.48 g; p = 0.007) and LVM index (LVMI) (allopurinol -2.2 ± 2.78 g/m(2) vs. placebo -0.53 ± 2.5 g/m(2); p = 0.023). The absolute mean difference between groups for change in LVM and LVMI was -3.89 g (95% confidence interval: -1.1 to -6.7) and -1.67 g/m(2) (95% confidence interval: -0.23 to -3.1), respectively. Allopurinol also reduced LV end-systolic volume (allopurinol -2.81 ± 7.8 mls vs. placebo +1.3 ± 7.22 mls; p = 0.047), improved FMD (allopurinol +0.82 ± 1.8% vs. placebo -0.69 ± 2.8%; p = 0.017) and augmentation index (allopurinol -2.8 ± 5.1% vs. placebo +0.9 ± 7%; p = 0.02). CONCLUSIONS: High-dose allopurinol regresses LVH, reduces LV end-systolic volume, and improves endothelial function in patients with IHD and LVH. This raises the possibility that allopurinol might reduce future cardiovascular events and mortality in these patients. (Does a Drug Allopurinol Reduce Heart Muscle Mass and Improve Blood Vessel Function in Patients With Normal Blood Pressure and Stable Angina?; ISRCTN73579730).


Assuntos
Alopurinol/administração & dosagem , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Isquemia Miocárdica/complicações , Idoso , Método Duplo-Cego , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Hipertrofia Ventricular Esquerda/etiologia , Imageamento por Ressonância Magnética , Masculino , Manometria
15.
J Am Soc Nephrol ; 22(7): 1382-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21719783

RESUMO

Allopurinol ameliorates endothelial dysfunction and arterial stiffness among patients without chronic kidney disease (CKD), but it is unknown if it has similar effects among patients with CKD. Furthermore, because arterial stiffness increases left ventricular afterload, any allopurinol-induced improvement in arterial compliance might also regress left ventricular hypertrophy (LVH). We conducted a randomized, double-blind, placebo-controlled, parallel-group study in patients with stage 3 CKD and LVH. We randomly assigned 67 subjects to allopurinol at 300 mg/d or placebo for 9 months; 53 patients completed the study. We measured left ventricular mass index (LVMI) with cardiac magnetic resonance imaging (MRI), assessed endothelial function by flow-mediated dilation (FMD) of the brachial artery, and evaluated central arterial stiffness by pulse-wave analysis. Allopurinol significantly reduced LVH (P=0.036), improved endothelial function (P=0.009), and improved the central augmentation index (P=0.015). This study demonstrates that allopurinol can regress left ventricular mass and improve endothelial function among patients with CKD. Because LVH and endothelial dysfunction associate with prognosis, these results call for further trials to examine whether allopurinol reduces cardiovascular events in patients with CKD and LVH.


Assuntos
Alopurinol/uso terapêutico , Antimetabólitos/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Insuficiência Renal Crônica/complicações , Idoso , Alopurinol/farmacologia , Antimetabólitos/farmacologia , Método Duplo-Cego , Feminino , Humanos , Hipertrofia Ventricular Esquerda/complicações , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/tratamento farmacológico , Xantina Oxidase/antagonistas & inibidores
16.
Cardiovasc Intervent Radiol ; 30(1): 42-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17122886

RESUMO

PURPOSE: To retrospectively evaluate the 10 year follow-up results in patients who had "kissing" self-expanding stent aortic bifurcation reconstruction. METHODS: Forty-three patients were treated with "kissing" self-expanding stents for aortoiliac occlusive disease. Early follow-up with clinical and ankle brachial pressure indices (ABPI) was performed at 3, 6, 12, and 24 months and with intra-arterial digital subtraction angiography at 12-24 months; clinical and angiographic follow-up was performed for symptom recurrence up to 10 years after treatment. Retrospective record review was performed to assess mortality, clinical patency, angiographic patency, and secondary assisted patency of both stents and downstream peripheral vessels at 5 and 10 years follow-up. RESULTS: The 2 year primary angiographic and secondary assisted stent patencies were 89% and 93%, respectively. At 10 years follow-up in 40 patients the mortality was 38% (due to myocardial infarction, stroke, chronic renal failure, malignancy, and liver failure). At 5 and 10 years follow-up the primary clinical stent patency was 82% and 68%, and the secondary assisted stent patency 93% and 86%, respectively. At 5 and 10 years, the distal vessel patency was 86% and 72%, and the secondary assisted distal vessel patency treated by surgical or endovascular techniques was 94% and 88%, respectively. At 10 years there was no limb loss. CONCLUSION: The long-term (10 year) results of aortic bifurcation arterial self-expanding stent placement in patients with arterial occlusive disease show a 10 year primary stent patency rate of 68% but a secondary assisted patency rate of 86%. In addition there is a high overall mortality due to other cardiovascular causes and the rate of distal disease progression and loss of patency is similar to the loss of stent patency rate.


Assuntos
Doenças da Aorta/cirurgia , Oclusão de Enxerto Vascular/diagnóstico , Doenças Vasculares Periféricas/terapia , Stents , Tempo , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão , Progressão da Doença , Feminino , Seguimentos , Humanos , Artéria Ilíaca/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Grau de Desobstrução Vascular
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