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1.
Radiology ; 308(1): e221428, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37489992

RESUMO

Background The optimal diagnostic pathway for prostate cancer (PCa) is evolving, requiring further evaluation in a randomized controlled trial. Purpose To assess the diagnostic accuracy of prebiopsy multiparametric MRI in the identification of clinically significant PCa (csPCa) using radical prostatectomy (RP) specimens as the reference standard, and to test the diagnostic accuracy of combined US and MRI fusion-targeted biopsy with systematic biopsies. Materials and Methods In a prospective randomized controlled trial including university hospitals, men with suspected PCa were recruited between January 2015 and August 2020 to assess the diagnostic accuracy of multiparametric MRI before biopsy in detection of csPCa at biopsy and RP histopathologic structure (primary outcome). Men with lesions suspicious for cancer (Prostate Imaging and Reporting Data System [PI-RADS] ≥3) at multiparametric MRI were first randomized to either systematic random prostate biopsies alone (control group) or US and MRI fusion-targeted biopsies with systematic random prostate biopsies (intervention group) at a one-to-one ratio to compare the diagnostic accuracy of systematic random versus combined fusion with systematic random biopsies (secondary outcome). A subset of recruited participants (n = 89) underwent RP and histologic sectioning. Results There were 582 participants who were eligible to undergo multiparametric MRI (mean age, 65 years ± 6 [SD]). In total, 413 had a PI-RADS score of at least 3 and were randomized into either the intervention group (207 of 413; 50.1%) or control group (206 of 413; 49.9%). The csPCa detection rate in the intervention group was higher, with an adjusted odds ratio of 1.79 (95% CI: 1.14, 2.79; P = .01). A subgroup of 89 men underwent RP (21.5%; 89 of 413). Multiparametric MRI helped correctly identify 131 of 182 csPCa foci in 89 men (sensitivity, 72%; 95% CI: 65, 78). The specificity, positive predictive value, and negative predictive value were 71% (91 of 128), 78% (131 of 168), and 64% (91 of 142), respectively. Conclusion Prebiopsy multiparametric MRI was accurate in the depiction of clinically significant PCa. Combining US and MRI fusion-targeted biopsies with systematic biopsies helped detect more clinically significant lesions than did systematic biopsies alone. Clinical trial registration no. NCT02745496 © RSNA, 2023 Supplemental material is available for this article.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Idoso , Imageamento por Ressonância Magnética , Estudos Prospectivos , Biópsia Guiada por Imagem
2.
Eur Heart J ; 41(36): 3421-3432, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32578850

RESUMO

AIM: We tested the hypothesis that dapagliflozin may regress left ventricular hypertrophy (LVH) in people with type 2 diabetes (T2D). METHODS AND RESULTS: We randomly assigned 66 people (mean age 67 ± 7 years, 38 males) with T2D, LVH, and controlled blood pressure (BP) to receive dapagliflozin 10 mg once daily or placebo for 12 months. Primary endpoint was change in absolute left ventricular mass (LVM), assessed by cardiac magnetic resonance imaging. In the intention-to-treat analysis, dapagliflozin significantly reduced LVM compared with placebo with an absolute mean change of -2.82g [95% confidence interval (CI): -5.13 to -0.51, P = 0.018]. Additional sensitivity analysis adjusting for baseline LVM, baseline BP, weight, and systolic BP change showed the LVM change to remain statistically significant (mean change -2.92g; 95% CI: -5.45 to -0.38, P = 0.025). Dapagliflozin significantly reduced pre-specified secondary endpoints including ambulatory 24-h systolic BP (P = 0.012), nocturnal systolic BP (P = 0.017), body weight (P < 0.001), visceral adipose tissue (VAT) (P < 0.001), subcutaneous adipose tissue (SCAT) (P = 0.001), insulin resistance, Homeostatic Model Assessment of Insulin Resistance (P = 0.017), and high-sensitivity C-reactive protein (hsCRP) (P = 0.049). CONCLUSION: Dapagliflozin treatment significantly reduced LVM in people with T2D and LVH. This reduction in LVM was accompanied by reductions in systolic BP, body weight, visceral and SCAT, insulin resistance, and hsCRP. The regression of LVM suggests dapagliflozin can initiate reverse remodelling and changes in left ventricular structure that may partly contribute to the cardio-protective effects of dapagliflozin. CLINICALTRIALS.GOV IDENTIFIER: NCT02956811.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Idoso , Compostos Benzidrílicos , Pressão Sanguínea , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos , Ventrículos do Coração , Humanos , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Hipertrofia Ventricular Esquerda/prevenção & controle , Masculino , Pessoa de Meia-Idade
3.
Age Ageing ; 49(6): 1003-1010, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-32318695

RESUMO

BACKGROUND: Allopurinol has vascular antioxidant effects and participates in purinergic signalling within muscle. We tested whether allopurinol could improve skeletal muscle energetics and physical function in older people with impaired physical performance. METHODS: We conducted a randomised, double blind, parallel group, placebo-controlled trial, comparing 20 weeks of allopurinol 600 mg once daily versus placebo. We recruited community-dwelling participants aged 65 and over with baseline 6-min walk distance of <400 m and no contraindications to magnetic resonance imaging scanning. Outcomes were measured at baseline and 20 weeks. The primary outcome was post-exercise phosphocreatine (PCr) recovery rate measured using 31P magnetic resonance spectroscopy of the calf. Secondary outcomes included 6-min walk distance, short physical performance battery (SPPB), lean body mass measured by bioimpedance, endothelial function and quality of life. RESULTS: In total, 124 participants were randomised, mean age 80 (SD 6) years. A total of 59 (48%) were female, baseline 6-min walk distance was 293 m (SD 80 m) and baseline SPPB was 8.5 (SD 2.0). Allopurinol did not significantly improve PCr recovery rate (treatment effect 0.10 units [95% CI, -0.07 to 0.27], P = 0.25). No significant changes were seen in endothelial function, quality of life, lean body mass or SPPB. Allopurinol improved 6-min walk distance (treatment effect 25 m [95% 4-46, P = 0.02]). This was more pronounced in those with high baseline oxidative stress and urate. CONCLUSION: Allopurinol improved 6-min walk distance but not PCr recovery rate in older people with impaired physical function. Antioxidant strategies to improve muscle function for older people may need to be targeted at subgroups with high baseline oxidative stress.


Assuntos
Alopurinol , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Alopurinol/efeitos adversos , Feminino , Humanos , Músculo Esquelético , Fosfocreatina , Caminhada
4.
Eur Heart J ; 40(41): 3409-3417, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30993313

RESUMO

AIM: We tested the hypothesis that metformin may regress left ventricular hypertrophy (LVH) in patients who have coronary artery disease (CAD), with insulin resistance (IR) and/or pre-diabetes. METHODS AND RESULTS: We randomly assigned 68 patients (mean age 65 ± 8 years) without diabetes who have CAD with IR and/or pre-diabetes to receive either metformin XL (2000 mg daily dose) or placebo for 12 months. Primary endpoint was change in left ventricular mass indexed to height1.7 (LVMI), assessed by magnetic resonance imaging. In the modified intention-to-treat analysis (n = 63), metformin treatment significantly reduced LVMI compared with placebo group (absolute mean difference -1.37 (95% confidence interval: -2.63 to -0.12, P = 0.033). Metformin also significantly reduced other secondary study endpoints such as: LVM (P = 0.032), body weight (P = 0.001), subcutaneous adipose tissue (P = 0.024), office systolic blood pressure (BP, P = 0.022) and concentration of thiobarbituric acid reactive substances, a biomarker for oxidative stress (P = 0.04). The glycated haemoglobin A1C concentration and fasting IR index did not differ between study groups at the end of the study. CONCLUSION: Metformin treatment significantly reduced LVMI, LVM, office systolic BP, body weight, and oxidative stress. Although LVH is a good surrogate marker of cardiovascular (CV) outcome, conclusive evidence for the cardio-protective role of metformin is required from large CV outcomes trials.


Assuntos
Doença da Artéria Coronariana/complicações , Hipertrofia Ventricular Esquerda , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Estado Pré-Diabético , Idoso , Peso Corporal/efeitos dos fármacos , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Resistência à Insulina , Masculino , Metformina/efeitos adversos , Metformina/farmacologia , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Estado Pré-Diabético/complicações , Estado Pré-Diabético/tratamento farmacológico , Resultado do Tratamento
5.
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.
J Cardiovasc Magn Reson ; 20(1): 7, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382349

RESUMO

BACKGROUND: Arteriosclerosis (arterial stiffening) is associated with future cardiovascular events, with this effect postulated to be due to its effect on cardiac afterload, atherosclerosis (plaque formation) progression or both, but with limited evidence examining these early in disease formation. The aim of the current study is to examine the association between arteriosclerosis, atherosclerosis and ventricular remodelling in a population at low-intermediate cardiovascular risk. METHODS: One thousand six hundred fifty-one subjects free of clinical cardiovascular disease and with a < 20% 10 year cardiovascular risk score underwent a cardiovascular magnetic resonance (CMR) study and whole body CMR angiogram. Arteriosclerosis was measured using total arterial compliance (TAC) - calculated as the indexed stroke volume divided by the pulse pressure. Atherosclerosis was quantified using a standardised atheroma score (SAS) which was calculated by scoring 30 arterial segments within the body based on the degree of stenosis, summating these scores and normalising it to the number of assessable segments. Left ventricular remodelling was measured using left ventricular mass to volume ratio (LVMVR). RESULTS: One thousand five hundred fifteen (38% male, 53.8 ± 8.2 years old) completed the study. On univariate analysis TAC was associated with SAS but this was lost after accounting for cardiovascular risk factors in both males (B = - 0.001 (- 0.004-0.002),p = 0.62) and females (B = 0.000(95%CI -0.002--0.002),p = 0.78). In contrast compliance correlated with LVMVR after accounting for cardiovascular risk factors (B = - 0.12(95%CI -0.16--0.091),p < 0.001 in males; B = - 0.12(95%CI -0.15--0.086),p < 0.001 in females). CONCLUSION: Systemic arteriosclerosis is associated with left ventricular remodelling but not atherosclerosis. Future efforts in cardiovascular risk prevention should thus seek to address both arteriosclerosis and atherosclerosis individually.


Assuntos
Arteriosclerose/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Angiografia por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Doença Arterial Periférica/diagnóstico por imagem , Rigidez Vascular , Função Ventricular Esquerda , Remodelação Ventricular , Arteriosclerose/fisiopatologia , Estudos de Casos e Controles , Feminino , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/fisiopatologia , Placa Aterosclerótica , Valor Preditivo dos Testes , Prognóstico , Imagem Corporal Total
7.
MAGMA ; 31(6): 735-745, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30132298

RESUMO

OBJECTIVE: To compare non-contrast enhanced MRI with ultrasound (US) for measurement of arm blood vessel geometries and flow velocities in volunteers and patients with end-stage renal disease. MATERIALS AND METHODS: Subjects were scanned using US (reference standard), and MRI 2D time-of-flight (ToF), 2D phase contrast (PC), and 3D multi-echo data image combination (MEDIC). Patients were also scanned after arteriovenous fistula (AVF) surgery. RESULTS: For mean vessel diameters (radial and brachial arteries; cephalic vein) MEDIC measurements were similar to US (p > 0.05). However, ToF underestimated the mean diameter of the cephalic vein relative to US (p < 0.05). For arterial velocity measurements, the mean values derived by PC-MR and US were similar (p > 0.05). Post-operatively, the intra-luminal signal intensity was hypo-intense at the anastomosis site using ToF and MEDIC. At the same site the outer boundary of the vessel was consistently lost on ToF, but remained clearly delineated on the MEDIC images. DISCUSSION: With the exception of ToF, the MRI data demonstrated excellent agreement with US for measurements of vessel geometry and flow velocity. Further, the ability to clearly delineate the post-surgery vessel edges with MEDIC MRI suggests that the technique may be useful for surveillance after AVF creation or for patient-specific modelling studies.


Assuntos
Fístula Arteriovenosa/diagnóstico por imagem , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/cirurgia , Imageamento por Ressonância Magnética/métodos , Diálise Renal/efeitos adversos , Adulto , Derivação Arteriovenosa Cirúrgica , Velocidade do Fluxo Sanguíneo , Artéria Braquial/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Pessoa de Meia-Idade , Projetos Piloto , Período Pré-Operatório , Artéria Radial/cirurgia , Diálise Renal/métodos , Ultrassonografia
8.
BMC Cardiovasc Disord ; 17(1): 118, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28486936

RESUMO

BACKGROUND: Carotid-femoral pulse wave velocity (cf-PWV) and aortic PWV measured using MRI (MRI-PWV) show good correlation, but with a significant and consistent bias across studies. The aim of the current study was to evaluate whether the differences between cf.-PWV and MRI-PWV can be accounted for by inaccuracies of currently used distance measurements. METHODS: One hundred fourteen study participants were recruited into one of 4 groups: Type 2 diabetes melltus (T2DM) with cardiovascular disease (CVD) (n = 23), T2DM without CVD (n = 41), CVD without T2DM (n = 25) and a control group (n = 25). All participants underwent cf.-PWV, cardiac MRI and whole body MR angiography(WB-MRA). 90 study participants also underwent aortic PWV using MRI. cf.-PWVEXT was performed using a SphygmoCor device (Atcor Medical, West Ryde, Australia). The true intra-arterial pathlength was measured using the WB-MRA and then used to recalculate the cf.-PWVEXT to give a cf.-PWVMRA. RESULTS: Distance measurements were significantly lower on WB-MRA than on external tape measure (mean diff = -85.4 ± 54.0 mm,p < 0.001). MRI-PWV was significantly lower than cf.-PWVEXT (MRI-PWV = 8.1 ± 2.9 vs. cf.-PWVEXT = 10.9 ± 2.7 ms-1,p < 0.001). When cf.-PWV was recalculated using the inter-arterial distance from WB-MRA, this difference was significantly reduced but not lost (MRI-PWV = 8.1 ± 2.9 ms-1 vs. cf.-PWVMRA 9.1 ± 2.1 ms-1, mean diff = -0.96 ± 2.52 ms-1,p = 0.001). Recalculation of the PWV increased correlation with age and pulse pressure. CONCLUSION: Differences in cf.-PWV and MRI PWV can be predominantly but not entirely explained by inaccuracies introduced by the use of simple surface measurements to represent the convoluted arterial path between the carotid and femoral arteries.


Assuntos
Aorta/diagnóstico por imagem , Doenças Cardiovasculares/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/diagnóstico por imagem , Artéria Femoral/diagnóstico por imagem , Angiografia por Ressonância Magnética , Manometria , Análise de Onda de Pulso/métodos , Rigidez Vascular , Idoso , Aorta/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Artérias Carótidas/fisiopatologia , Diabetes Mellitus Tipo 2/diagnóstico , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/fisiopatologia , Feminino , Artéria Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Imagem Corporal Total
9.
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
10.
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
11.
Acta Radiol ; 57(12): 1468-1475, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26861203

RESUMO

Background Left ventricular (LV) function has traditionally been the focus for cardiac magnetic resonance imaging (MRI) investigations, but similar methods can also be applied to the left atrium (LA). Previous studies elsewhere have almost entirely involved the use of 1.5T systems, but 3T MRI can provide faster data acquisition with thinner image slices, and may be more suitable for quantifying the structure and function of the LA. Purpose To evaluate 3T-MRI for LA volume assessments in: (i) healthy volunteers (HV); (ii) patients with LV-hypertrophy and ischemia (LVHI); and (iii) patients with LV-hypertrophy and diabetes (LVHD). Material and Methods Participants were imaged using a balanced steady-state free precession sequence. Healthy volunteers were scanned twice and patients were scanned on one occasion. Volumes were segmented by two observers, and coefficients of repeatability (CoR) were derived. Results For LA volumes (indexed to body surface area), CoRs were in the range of 1.3-4.6 mL/m2. The LVHI patients had enlarged LA volumes (diastolic, 46.4 mL/m2; systolic, 25.9 mL/m2) and reduced ejection fraction (EF) (44.9%) relative to the HV (diastolic, 39.0 mL/m2; systolic, 17.8 mL/m2; EF, 54.5%) and LVHD groups (diastolic, 41.4 mL/m2; systolic, 20.2 mL/m2; EF, 50.7%). LA volumes were moderately correlated with LV mass in the HV group (R2 = 0.59 for LA end-systolic volume), but became weaker (R2 ≤ 0.17) for patient groups. Conclusion 3T-MRI derived LA volume measurements are simple and repeatable, and can elicit clear differences between LVHI patients and HVs. These MRI endpoints provide scope for improved radiological interpretation of LA structure and function, and the high degree of repeatability validates their use for longitudinal investigations where precision work is essential.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
12.
Cardiovasc Diabetol ; 14: 122, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26382729

RESUMO

BACKGROUND: Whole body cardiovascular MR (WB CVMR) combines whole body angiography and cardiac MR assessment. It is accepted that there is a high disease burden in patients with diabetes, however the quantification of the whole body atheroma burden in both arterial and cardiac disease has not been previously reported. In this study we compare the quantified atheroma burden in those individuals with and without diabetes by clinical cardiovascular disease (CVD) status. METHODS: 158 participants underwent WB CVMR, and were categorised into one of four groups: (1) type 2 diabetes mellitus (T2DM) with CVD; (2) T2DM without CVD; (3) CVD without T2DM; (4) healthy controls. 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. Cardiac MR and late gadolinium enhancement images of the left ventricle were obtained for assessment of mass, volume and myocardial scar assessment. RESULTS: 148 participants completed the study protocol--61% male, with mean age of 64 ± 8.2 years. SAS was highest in those with cardiovascular disease without diabetes [10.1 (0-39.5)], followed by those with T2DM and CVD [4 (0-41.1)], then those with T2DM only [3.23 (0-19.4)] with healthy controls having the lowest atheroma score [2.4 (0-19.4)]. Both groups with a prior history of CVD had a higher SAS and left ventricular mass than those without (p < 0.001 for both). However after accounting for known cardiovascular risk factors, only the SAS in the group with CVD without T2DM remained significantly elevated. 6% of the T2DM group had evidence of silent myocardial infarct, with this subcohort having a higher SAS than the remainder of the T2DM group [7.7 (4-19) vs. 2.8 (0-17), p = 0.024]. CONCLUSIONS: Global atheroma burden was significantly higher in those with known cardiovascular disease and without diabetes but not in those with diabetes and cardiovascular disease suggesting that cardiovascular events may occur at a lower atheroma burden in diabetes.


Assuntos
Aterosclerose/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/diagnóstico , Cardiopatias/diagnóstico , Angiografia por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Imagem Corporal Total/métodos , Idoso , Aterosclerose/etiologia , Estudos de Casos e Controles , Meios de Contraste , Diabetes Mellitus Tipo 2/diagnóstico , Angiopatias Diabéticas/etiologia , Feminino , Cardiopatias/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
13.
Clin Endocrinol (Oxf) ; 79(4): 484-90, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23469866

RESUMO

OBJECTIVE: The significant role of corticosteroids in hypertension and cardiovascular disease highlights the importance of the adrenal gland in these disorders. The ability to correlate corticosteroid production with adrenal volume offers a novel research tool and intermediate phenotype in cardiovascular disease. The aim of this study was to develop and validate the use of magnetic resonance imaging (MRI) in adrenal volume assessment and investigate whether this associates with corticosteroid production. DESIGN/METHODS: Twenty normotensive men underwent noncontrast 1·5T MRI scanning of adrenals, measurement of blood pressure and plasma corticosteroids. Left adrenal volume was calculated twice using standard segmentation software by four independent observers with differing levels of clinical expertise and segmentation experience. To optimize this process, adrenal 'phantoms' with known fixed volumes underwent MRI scanning and analysis by two observers. RESULTS: Intra-observer coefficients of repeatability (CoRs) in phantoms ranged from 0·23 to 0·43 ml (interobserver CoR 0·48 ml). In the subject group, mean adrenal volumes were 3·99-5·82 ml with intra-observer CoRs 0·27-1·94 ml. Interobserver variability was 2·73 ml. Segmentation expertise was the main factor affecting variability, with experienced observers having the lowest CoRs; clinical knowledge was a factor when combined with segmentation experience. Mean adrenal volume correlated with plasma glucocorticoids (r = 0·523, P < 0·05) and aldosterone (r = 0·515, P < 0·05) for the most experienced observer only. CONCLUSIONS: Measurement of adrenal volume using MRI is challenging; most accurate volumes are achieved using a single observer with both segmentation experience and anatomical knowledge. The data also provide novel preliminary evidence that adrenal gland volume may be associated with plasma corticosteroid concentrations supporting further study of adrenal volume and steroid production across a range of blood pressures.


Assuntos
Corticosteroides/sangue , Glândulas Suprarrenais/anatomia & histologia , Pressão Sanguínea/fisiologia , Imageamento por Ressonância Magnética/métodos , Adulto , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Variações Dependentes do Observador , Projetos Piloto , Análise de Regressão , Reprodutibilidade dos Testes
14.
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
15.
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
16.
Kidney Int Rep ; 6(1): 146-155, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33426394

RESUMO

INTRODUCTION: Increased left ventricular mass index (LVMI) is associated with mortality in end-stage renal disease. LVMI regression may improve outcomes. Allopurinol has reduced LVMI in randomized controlled trials in chronic kidney disease, diabetes, and ischemic heart disease. This study investigated whether allopurinol would regress LVMI in hemodialysis patients. METHODS: This was a randomized placebo-controlled double-blind multicenter trial funded by the British Heart Foundation (PG/12/72/29743). A total of 80 patients undergoing regular maintenance hemodialysis were recruited from NHS Tayside, NHS Greater Glasgow and Clyde and NHS Ayrshire and Arran in Scotland, UK. Participants were randomly assigned on a 1:1 ratio to 12 months of therapy with allopurinol 300 mg or placebo after each dialysis session. The primary outcome was change in LVMI, as assessed by cardiac magnetic resonance imaging (CMRI) at baseline and 12 months. Secondary outcomes were change in BP, flow-mediated dilation (FMD), augmentation indices (AIx), and pulse wave velocity (PWV). RESULTS: A total of 53 patients, with a mean age of 58 years, completed the study and had CMRI follow-up data for analysis. Allopurinol did not regress LVMI (change in LVMI: placebo +3.6 ± 10.4 g/m2; allopurinol: +1.6 ± 11 g/m2; P = 0.49). Allopurinol had no demonstrable effect on BP, FMD, AIx, or PWV. CONCLUSION: Compared with placebo, treatment with allopurinol did not regress LVMI in this trial.

17.
Diabetes Care ; 43(6): 1356-1359, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32245746

RESUMO

OBJECTIVE: To determine the effects of dapagliflozin in patients with heart failure (HF) and type 2 diabetes mellitus (T2DM) on left ventricular (LV) remodeling using cardiac MRI. RESEARCH DESIGN AND METHODS: We randomized 56 patients with T2DM and HF with LV systolic dysfunction to dapagliflozin 10 mg daily or placebo for 1 year, on top of usual therapy. The primary end point was difference in LV end-systolic volume (LVESV) using cardiac MRI. Key secondary end points included other measures of LV remodeling and clinical and biochemical parameters. RESULTS: In our cohort, dapagliflozin had no effect on LVESV or any other parameter of LV remodeling. However, it reduced diastolic blood pressure and loop diuretic requirements while increasing hemoglobin, hematocrit, and ketone bodies. There was a trend toward lower weight. CONCLUSIONS: We were unable to determine with certainty whether dapagliflozin in patients with T2DM and HF had any effect on LV remodeling. Whether the benefits of dapagliflozin in HF are due to remodeling or other mechanisms remains unknown.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Remodelação Ventricular/efeitos dos fármacos , Idoso , Compostos Benzidrílicos/farmacologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/fisiopatologia , Feminino , Glucosídeos/farmacologia , Insuficiência Cardíaca/etiologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/tratamento farmacológico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação Ventricular/fisiologia
18.
J Magn Reson Imaging ; 30(5): 1059-67, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19856438

RESUMO

PURPOSE: To optimize the contrast agent dose and delivery rate used in a novel whole-body magnetic resonance angiography (MRA) protocol using a 3.0T MR scanner. MATERIALS AND METHODS: Six groups of 20 consenting volunteers underwent whole-body MRA, with each group receiving a different contrast dose and contrast delivery rate. The arterial tree was divided into 16 segments and the image quality at each of the anatomical locations, covering the whole body, was assessed. Qualitative analysis was carried out using a scoring assessment of image quality, and quantitative assessments were performed by measuring contrast-to-noise (CNR) and a signal-to-noise (SNR) index. RESULTS: Reducing the contrast dose from 40 mL to 25 mL was found to significantly increase the CNR in several vessels of interest in the arterial tree. There was also a significant increase in the qualitative image quality score (P < 0.001). CONCLUSION: This study demonstrates that reducing the contrast dose at 3.0T can result in an increase in the CNR in the vessels of interest without significantly affecting the SNR.


Assuntos
Angiografia/métodos , Aterosclerose/patologia , Meios de Contraste/administração & dosagem , Meios de Contraste/farmacologia , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Artefatos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Risco , Imagem Corporal Total
19.
Invest Radiol ; 54(3): 169-176, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30394963

RESUMO

OBJECTIVES: The aim of this study was to examine the variation in signal intensity ratio (SIR) values in Eurospin gel phantoms and healthy volunteer (HV) brain images in response to different magnetic resonance imaging hardware and software settings. MATERIALS AND METHODS: Gel phantoms with T1 relaxation times similar to the dentate nucleus (DN), pons (P), globus palladus (GP), and thalamus (Th) were scanned using a T1-weighted 2-dimensional spin-echo sequence on 2 magnetic resonance imaging scanners (3 T and 1.5 T). Imaging was performed by sequentially altering selected magnetic resonance (MR) parameters relative to a default pulse sequence, and the protocol was implemented repeatedly over 3 months. The experiment was also repeated on a cohort of 15 young HVs. Calculations of DN/P and GP/Th SIR values were derived for the images of the gels (GelDN/P and GelGP/Th) and the HVs (HVDN/P and HVGP/Th). RESULTS: For the default sequence, the mean SIR values of GelDN/P and GelGP/Th varied by ±2.20% and ±0.75%, respectively, when measured over multiple imaging sessions (3 T). Within a single imaging session, these variations were smaller (±0.17% for GelDN/P and ±0.15% for GelGP/Th). At 1.5 T, the equivalent SIR variations for GelDN/P were ±1.41% (multiple sessions) and ±0.41% (single session), and that for GelGP/Th were ±0.47% (multiple sessions) and ±0.33% (single session).Sequential changes to the MR sequence parameters resulted in gel SIR variations as follows: 14.07% ± 2.43% (with/without normalization filters), -7.80% ± 0.28% (different echo times, TE), and -5.06% ± 0.59% (selective activation of RF coil elements). The largest variations were noted when the gels were positioned below the scanner isocenter, where SIR measurements were different by 22%.For the HVs, the SIR values were found to be consistently within 0.64% (single session) for the default sequence. Sequential changes to the MR sequence parameters resulted in SIR variations of -24.47% ± 2.47% (with/without normalization filters), -15.32% ± 7.71% (different echo times, TE), and -2.90% ± 0.78% (selective activation of RF coil elements). CONCLUSIONS: This study has demonstrated that SIR percentage changes from baseline of a similar magnitude to brain gadolinium contrast agent signal hyperintensities can be replicated in phantom models and HVs by altering common MR acquisition parameters and hardware.


Assuntos
Encéfalo/anatomia & histologia , Meios de Contraste , Gadolínio , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Adulto , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Valores de Referência , Estudos Retrospectivos
20.
Trials ; 20(1): 638, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752954

RESUMO

BACKGROUND: There is growing evidence suggesting that multiparametric magnetic resonance imaging (mpMRI) is a marker for prostate cancer (PCa) aggressiveness and could be used to plan treatment. Improving early detection of clinically significant PCa with pre-biopsy mpMRI would very likely have advantages including optimising the diagnosis and treatment of diseases and diminishing patient anxiety. METHODS AND MATERIALS: This is a prospective multicentre study of pre-biopsy mpMRI diagnostic test accuracy with subgroup randomisation at a 1:1 ratio with respect to transrectal ultrasound (TRUS) and MRI/US fusion-guided biopsy or TRUS-only biopsy. It is designed as a single-gate study with a single set of inclusion criteria. The total duration of the recruitment phase was 48 months; however, this has now been extended to 66 months. A sample size of 600 participants is required. DISCUSSION: The primary objective is to determine whether mpMRI can improve PCa detection and characterisation. The key secondary objective is to determine whether MRI/US fusion-guided biopsy can reduce the number of false-negative biopsies. Ethical approval was obtained from the East of Scotland Research Ethics Committee 1 (14/ES/1070) on 20 November 2014. The results of this study will be used for publication and presentation in national and international journals and at scientific conferences. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02745496. Retrospectively registered on 20 April 2016.


Assuntos
Detecção Precoce de Câncer , Biópsia Guiada por Imagem , Imagem por Ressonância Magnética Intervencionista , Neoplasias da Próstata/patologia , Adulto , Idoso , Detecção Precoce de Câncer/efeitos adversos , Reações Falso-Negativas , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Imagem por Ressonância Magnética Intervencionista/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Imagem Multimodal , Valor Preditivo dos Testes , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Escócia , Ultrassonografia de Intervenção
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