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1.
Vasc Med ; 24(5): 414-421, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31277561

RESUMO

Extensive atherosclerotic plaque burden in the lower extremities often leads to symptomatic peripheral artery disease (PAD) including impaired walking performance and claudication. Interleukin-1ß (IL-1ß) may play an important pro-inflammatory role in the pathogenesis of this disease. Interruption of IL-1ß signaling was hypothesized to decrease plaque progression in the leg macrovasculature and improve the mobility of patients with PAD with intermittent claudication. Thirty-eight patients (mean age 65 years; 71% male) with symptomatic PAD (confirmed by ankle-brachial index) were randomized 1:1 to receive canakinumab (150 mg subcutaneously) or placebo monthly for up to 12 months. The mean vessel wall area (by 3.0 T black-blood magnetic resonance imaging (MRI)) of the superficial femoral artery (SFA) was used to measure plaque volume. Mobility was assessed using the 6-minute walk test. Canakinumab was safe and well tolerated. Markers of systemic inflammation (interleukin-6 and high-sensitivity C-reactive protein) fell as early as 1 month after treatment. MRI (32 patients at 3 months; 21 patients at 12 months) showed no evidence of plaque progression in the SFA in either placebo-treated or canakinumab-treated patients. Although an exploratory endpoint, placebo-adjusted maximum and pain-free walking distance (58 m) improved as early as 3 months after treatment with canakinumab when compared with placebo. Although canakinumab did not alter plaque progression in the SFA, there is an early signal that it may improve maximum and pain-free walking distance in patients with symptomatic PAD. Larger studies aimed at this endpoint will be required to definitively demonstrate this. ClinicalTrials.gov Identifier: NCT01731990.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Claudicação Intermitente/tratamento farmacológico , Doença Arterial Periférica/tratamento farmacológico , Idoso , Anti-Inflamatórios/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Biomarcadores/sangue , Método Duplo-Cego , Tolerância ao Exercício/efeitos dos fármacos , Feminino , Alemanha , Humanos , Mediadores da Inflamação/sangue , Claudicação Intermitente/sangue , Claudicação Intermitente/diagnóstico , Claudicação Intermitente/fisiopatologia , Jordânia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/sangue , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Estudo de Prova de Conceito , Estudos Prospectivos , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
3.
J Magn Reson Imaging ; 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29504181

RESUMO

BACKGROUND: To support translational lung MRI research with hyperpolarized 129 Xe gas, comprehensive evaluation of derived quantitative lung function measures against established measures from 3 He MRI is required. Few comparative studies have been performed to date, only at 3T, and multisession repeatability of 129 Xe functional metrics have not been reported. PURPOSE/HYPOTHESIS: To compare hyperpolarized 129 Xe and 3 He MRI-derived quantitative metrics of lung ventilation and microstructure, and their repeatability, at 1.5T. STUDY TYPE: Retrospective. POPULATION: Fourteen healthy nonsmokers (HN), five exsmokers (ES), five patients with chronic obstructive pulmonary disease (COPD), and 16 patients with nonsmall-cell lung cancer (NSCLC). FIELD STRENGTH/SEQUENCE: 1.5T. NSCLC, COPD patients and selected HN subjects underwent 3D balanced steady-state free-precession lung ventilation MRI using both 3 He and 129 Xe. Selected HN, all ES, and COPD patients underwent 2D multislice spoiled gradient-echo diffusion-weighted lung MRI using both hyperpolarized gas nuclei. ASSESSMENT: Ventilated volume percentages (VV%) and mean apparent diffusion coefficients (ADC) were derived from imaging. COPD patients performed the whole MR protocol in four separate scan sessions to assess repeatability. Same-day pulmonary function tests were performed. STATISTICAL TESTS: Intermetric correlations: Spearman's coefficient. Intergroup/internuclei differences: analysis of variance / Wilcoxon's signed rank. Repeatability: coefficient of variation (CV), intraclass correlation (ICC) coefficient. RESULTS: A significant positive correlation between 3 He and 129 Xe VV% was observed (r = 0.860, P < 0.001). VV% was larger for 3 He than 129 Xe (P = 0.001); average bias, 8.79%. A strong correlation between mean 3 He and 129 Xe ADC was obtained (r = 0.922, P < 0.001). MR parameters exhibited good correlations with pulmonary function tests. In COPD patients, mean CV of 3 He and 129 Xe VV% was 4.08% and 13.01%, respectively, with ICC coefficients of 0.541 (P = 0.061) and 0.458 (P = 0.095). Mean 3 He and 129 Xe ADC values were highly repeatable (mean CV: 2.98%, 2.77%, respectively; ICC: 0.995, P < 0.001; 0.936, P < 0.001). DATA CONCLUSION: 129 Xe lung MRI provides near-equivalent information to 3 He for quantitative lung ventilation and microstructural MRI at 1.5T. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2018.

4.
Magn Reson Med ; 77(6): 2107-2113, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27366901

RESUMO

PURPOSE: To evaluate the reproducibility of indices of lung microstructure and function derived from 129 Xe chemical shift saturation recovery (CSSR) spectroscopy in healthy volunteers and patients with chronic obstructive pulmonary disease (COPD), and to study the sensitivity of CSSR-derived parameters to pulse sequence design and lung inflation level. METHODS: Preliminary data were collected from five volunteers on three occasions, using two implementations of the CSSR sequence. Separately, three volunteers each underwent CSSR at three different lung inflation levels. After analysis of these preliminary data, five COPD patients were scanned on three separate days, and nine age-matched volunteers were scanned three times on one day, to assess reproducibility. RESULTS: CSSR-derived alveolar septal thickness (ST) and surface-area-to-volume (S/V) ratio values decreased with lung inflation level (P < 0.001; P = 0.057, respectively). Intra-subject standard deviations of ST were lower than the previously measured differences between volunteers and subjects with interstitial lung disease. The mean coefficient of variation (CV) values of ST were 3.9 ± 1.9% and 6.0 ± 4.5% in volunteers and COPD patients, respectively, similar to CV values for whole-lung carbon monoxide diffusing capacity. The mean CV of S/V in volunteers and patients was 14.1 ± 8.0% and 18.0 ± 19.3%, respectively. CONCLUSION: 129 Xe CSSR presents a reproducible method for estimation of alveolar septal thickness. Magn Reson Med 77:2107-2113, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.


Assuntos
Pulmão/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Doença Pulmonar Obstrutiva Crônica/patologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Troca Gasosa Pulmonar/fisiologia , Isótopos de Xenônio/farmacocinética , Administração por Inalação , Adulto , Idoso , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Isótopos de Xenônio/administração & dosagem
5.
Artigo em Inglês | MEDLINE | ID: mdl-38701435

RESUMO

Clonal hematopoiesis (CH) is more common in older persons and has been associated with an increased risk of hematological cancers and cardiovascular diseases. The most common CH mutations occur in the DNMT3A and TET2 genes and result in increased pro-inflammatory signaling. The Canakinumab Anti-inflammatory Thrombosis Outcome Study (CANTOS, NCT01327846) evaluated the neutralizing anti-IL-1ß antibody canakinumab in 10,061 randomized patients with a history of myocardial infarction and persistent inflammation; DNA samples were available from 3,923 patients for targeted genomic sequencing. We examined the incidence of non-hematological malignancy by treatment assignment and CH mutations and estimated the cumulative incidence of malignancy events during trial follow-up. Patients with TET2 mutations treated with canakinumab had the lowest incidence of non-hematological malignancy across cancer types. The cumulative incidence of at least one reported malignancy was lower for patients with TET2 mutations treated with canakinumab vs those treated with placebo. These findings support a potential role for canakinumab in cancer prevention and provide evidence of IL-1ß blockade cooperating with CH mutations to modify the disease course.

6.
J Am Heart Assoc ; 13(13): e033544, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38904251

RESUMO

BACKGROUND: Prognostic markers and biological pathways linked to detrimental clinical outcomes in heart failure with preserved ejection fraction (HFpEF) remain incompletely defined. METHODS AND RESULTS: We measured serum levels of 4123 unique proteins in 1117 patients with HFpEF enrolled in the PARAGON-HF (Efficacy and Safety of LCZ696 Compared to Valsartan, on Morbidity and Mortality in Heart Failure Patients With Preserved Ejection Fraction) trial using a modified aptamer proteomic assay. Baseline circulating protein concentrations significantly associated with the primary end point and the timing and occurrence of total heart failure hospitalization and cardiovascular death were identified by recurrent events regression, accounting for multiple testing, adjusted for age, sex, treatment, and anticoagulant use, and compared with published analyses in 2515 patients with heart failure with reduced ejection fraction from the PARADIGM-HF (Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) and ATMOSPHERE (Efficacy and Safety of Aliskiren and Aliskiren/Enalapril Combination on Morbidity-Mortality in Patients With Chronic Heart Failure) clinical trials. We identified 288 proteins that were robustly associated with the risk of heart failure hospitalization and cardiovascular death in patients with HFpEF. The baseline proteins most strongly related to outcomes included B2M (ß-2 microglobulin), TIMP1 (tissue inhibitor of matrix metalloproteinase 1), SERPINA4 (serpin family A member 4), and SVEP1 (sushi, von Willebrand factor type A, EGF, and pentraxin domain containing 1). Overall, the protein-outcome associations in patients with HFpEF did not markedly differ as compared with patients with heart failure with reduced ejection fraction. A proteomic risk score derived in patients with HFpEF was not superior to a previous proteomic score derived in heart failure with reduced ejection fraction nor to clinical risk factors, NT-proBNP (N-terminal pro-B-type natriuretic peptide), or high-sensitivity cardiac troponin. CONCLUSIONS: Numerous serum proteins linked to metabolic, coagulation, and extracellular matrix regulatory pathways were associated with worse HFpEF prognosis in the PARAGON-HF proteomic substudy. Our results demonstrate substantial similarities among serum proteomic risk markers for heart failure hospitalization and cardiovascular death when comparing clinical trial participants with heart failure across the ejection fraction spectrum. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique Identifiers: NCT01920711, NCT01035255, NCT00853658.


Assuntos
Aminobutiratos , Biomarcadores , Combinação de Medicamentos , Insuficiência Cardíaca , Proteômica , Volume Sistólico , Tetrazóis , Valsartana , Humanos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/mortalidade , Proteômica/métodos , Masculino , Feminino , Idoso , Biomarcadores/sangue , Valsartana/uso terapêutico , Volume Sistólico/fisiologia , Aminobutiratos/uso terapêutico , Pessoa de Meia-Idade , Tetrazóis/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Prognóstico , Função Ventricular Esquerda
7.
Eur Heart J Case Rep ; 7(9): ytad416, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37662582

RESUMO

Background: Glagov et al. showed that no reduction in vessel lumen occurred until the atherosclerotic plaque burden exceeded 40% of the vessel area. Most major adverse cardiac events occurring in the first 4 years after a myocardial infarction arise from untreated angiographically mild, non-flow-limiting lesions at the time of the index event. We report how computed tomography (CT) coronary angiography (CCTA) can be used to non-invasively risk stratify a patient with non-obstructive coronary artery disease (CAD) and guide further management. Case summary: A 69-year-old non-smoking female with hypertension, dyslipidaemia, and hypothyroidism presented with atypical chest pain. Electrocardiogram and left ventricular ejection fraction were normal. Her lipidic profile was normal. CCTA showed a lipid-rich plaque with very low attenuation (<30 HU) in the left main stem (LMS) extending into the proximal left anterior descending (LAD) and in the mid LAD artery. The maximum plaque burden in the LMS was 67% with a remodelling index of 1.375, and an area stenosis of 22%. Tissue characterization showed a lipid-rich plaque with a thin fibrous cap. The perivascular fat attenuation index (FAI) in the proximal LAD was suggestive of (-69 HU) inflamed perivascular fat. Shear stress analysis of the LMS plaque showed normal wall shear stress (WSS); however, the axial plaque stress was high. Her medications were intensified to rosuvastatin 20 mg once daily (OD) and ezetimibe 10 mg OD. The patient remained asymptomatic at 6 months follow-up. Discussion: Our case exemplifies the value of CCTA as a diagnostic 'one-stop shop' (CCTA, finite element analysis, computed tomographic density [CTD], tissue characterization analysis, FAI analysis, WSS and wall strain, and etc.) when stratifying a patient with non-obstructive CAD. With further development of novel potent anti-lipidaemic and anti-inflammatory drugs, non-obstructive lesions with adverse plaque and haemodynamic parameters will have the opportunity to be treated with additional preventive pharmacological therapy.

8.
Blood Adv ; 7(24): 7471-7484, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-37934948

RESUMO

Canakinumab, a monoclonal antibody targeting proinflammatory cytokine interleukin-1ß (IL-1ß), improved hemoglobin levels while preventing recurrent cardiovascular events in the Canakinumab Anti-inflammatory Thrombosis Outcomes Study (CANTOS). This cardiovascular (CV) preventive effect was greater in patients with TET2 mutations associated with clonal hematopoiesis (CH). The current proteogenomic analysis aimed to understand the clinical response to canakinumab and underlying proteomic profiles in the context of CH and anemia. The analysis included 4595 patients from the CANTOS study who received either canakinumab or placebo and evaluated multiplexed proteomics (4785 proteins) using SomaScan and targeted deep sequencing for CH mutations. Incident anemia was more common in the presence of CH mutations but reduced by canakinumab treatment. Canakinumab treatment was significantly associated with higher hemoglobin increment in patients with concurrent CH mutations and anemia than patients with CH mutations without anemia or without CH mutations. Compared with those without CH mutations, the presence of CH mutations was associated with proteomic signatures of inflammation and defense response to infection, as well as markers of high-risk CV disease which was further enhanced by the presence of anemia. Canakinumab suppressed hepcidin, proinflammatory cytokines, myeloid activation, and complement pathways, and reversed pathologically deregulated pathways to a greater extent in patients with CH mutations and anemia. These molecular findings provide evidence of the clinical use of IL-1ß blockade and support further study of canakinumab for patients with concurrent anemia and CH mutations. This study was registered at www.clinicaltrials.gov as #NCT01327846.


Assuntos
Anemia , Anticorpos Monoclonais Humanizados , Hematopoiese Clonal , Proteínas de Ligação a DNA , Dioxigenases , Interleucina-1beta , Humanos , Anemia/tratamento farmacológico , Anemia/etiologia , Hematopoiese Clonal/genética , Citocinas , Hemoglobinas , Interleucina-1beta/antagonistas & inibidores , Proteômica , Anticorpos Monoclonais Humanizados/uso terapêutico , Proteínas de Ligação a DNA/genética , Dioxigenases/genética
9.
Cardiovasc Res ; 117(1): 320-329, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32065620

RESUMO

AIMS: The effects of serelaxin, a recombinant form of human relaxin-2 peptide, on vascular function in the coronary microvascular and systemic macrovascular circulation remain largely unknown. This mechanistic, clinical study assessed the effects of serelaxin on myocardial perfusion, aortic stiffness, and safety in patients with stable coronary artery disease (CAD). METHODS AND RESULTS: In this multicentre, double-blind, parallel-group, placebo-controlled study, 58 patients were randomized 1:1 to 48 h intravenous infusion of serelaxin (30 µg/kg/day) or matching placebo. The primary endpoints were change from baseline to 47 h post-initiation of the infusion in global myocardial perfusion reserve (MPR) assessed using adenosine stress perfusion cardiac magnetic resonance imaging, and applanation tonometry-derived augmentation index (AIx). Secondary endpoints were: change from baseline in AIx and pulse wave velocity, assessed at 47 h, Day 30, and Day 180; aortic distensibility at 47 h; pharmacokinetics and safety. Exploratory endpoints were the effect on cardiorenal biomarkers [N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity troponin T (hsTnT), endothelin-1, and cystatin C]. Of 58 patients, 51 were included in the primary analysis (serelaxin, n = 25; placebo, n = 26). After 2 and 6 h of serelaxin infusion, mean placebo-corrected blood pressure reductions of -9.6 mmHg (P = 0.01) and -13.5 mmHg (P = 0.0003) for systolic blood pressure and -5.2 mmHg (P = 0.02) and -8.4 mmHg (P = 0.001) for diastolic blood pressure occurred. There were no between-group differences from baseline to 47 h in global MPR (-0.24 vs. -0.13, P = 0.44) or AIx (3.49% vs. 0.04%, P = 0.21) with serelaxin compared with placebo. Endothelin-1 and cystatin C levels decreased from baseline in the serelaxin group, and there were no clinically relevant changes observed with serelaxin for NT-proBNP or hsTnT. Similar numbers of serious adverse events were observed in both groups (serelaxin, n = 5; placebo, n = 7) to 180-day follow-up. CONCLUSION: In patients with stable CAD, 48 h intravenous serelaxin reduced blood pressure but did not alter myocardial perfusion.


Assuntos
Pressão Arterial/efeitos dos fármacos , Doença da Artéria Coronariana/tratamento farmacológico , Circulação Coronária/efeitos dos fármacos , Relaxina/uso terapêutico , Rigidez Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Idoso , Biomarcadores/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Manometria , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio , Estudos Prospectivos , Análise de Onda de Pulso , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Relaxina/efeitos adversos , Relaxina/farmacocinética , Resultado do Tratamento , Reino Unido , Vasodilatadores/efeitos adversos , Vasodilatadores/farmacocinética
10.
Int J Chron Obstruct Pulmon Dis ; 15: 2399-2409, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116455

RESUMO

Rationale: Excess mucus plays a key role in COPD pathogenesis. Cigarette smoke-induced cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction may contribute to disease pathogenesis by depleting airway surface liquid and reducing mucociliary transport; these defects can be corrected in vitro by potentiating CFTR. Objective: To assess the efficacy of the CFTR potentiator icenticaftor in improving airflow obstruction in COPD patients with symptoms of chronic bronchitis. Methods: In this double-blind, placebo-controlled study, COPD patients were randomized (2:1) to either icenticaftor 300 mg or placebo b.i.d. This non-confirmatory proof of concept study was powered for lung clearance index (LCI) and pre-bronchodilator FEV1, with an estimated sample size of 90 patients. The primary endpoint was change from baseline in LCI for icenticaftor versus placebo at Day 29; key secondary endpoints included change from baseline in pre- and post-bronchodilator FEV1 on Day 29. Key exploratory endpoints included change from baseline in sweat chloride, plasma fibrinogen levels, and sputum colonization. Results: Ninety-two patients were randomized (icenticaftor, n=64; placebo, n=28). At Day 29, icenticaftor showed no improvement in change in LCI (treatment difference: 0.28 [19% probability of being better than placebo]), an improvement in pre-bronchodilator FEV1 (mean: 50 mL [84% probability]) and an improvement in post-bronchodilator FEV1 (mean: 63 mL [91% probability]) over placebo. Improvements in sweat chloride, fibrinogen and sputum bacterial colonization were also observed. Icenticaftor was safe and well tolerated. Conclusion: The CFTR potentiator icenticaftor increased FEV1 versus placebo after 28 days and was associated with improvements in systemic inflammation and sputum bacterial colonization in COPD patients; no improvements in LCI with icenticaftor were observed.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Quinolonas , Aminofenóis , Regulador de Condutância Transmembrana em Fibrose Cística , Método Duplo-Cego , Humanos , Depuração Mucociliar , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Quinolonas/efeitos adversos
11.
Pediatr Pulmonol ; 55(4): 929-938, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31962004

RESUMO

OBJECTIVE: To determine which outcome measures could detect early progression of disease in school-age children with mild cystic fibrosis (CF) lung disease over a two-year time interval utilizing chest computed tomography (CT) scores, quantitative CT air trapping (QAT), and spirometric measurements. METHODS: Thirty-six school-age children with mild CF lung disease (median [interquartile range] age 12 [3.7] years; percent predicted forced expiratory volume in 1 second (ppFEV1 ) 99 [12.5]) were evaluated by serial spirometer-controlled chest CT scans and spirometry at baseline, 3-month, 1- and 2-years. RESULTS: No significant changes were noted at 3-month for any variable except for decreased ppFEV1 . Mucus plugging score (MPS) and QATA1andA2 increased at 1- and 2-years. The bronchiectasis score (BS), and total score (TS) were increased at 2-year. All variables tested with the exception of bronchial wall thickness score, parenchymal score (PS), and ppFEV1 , were consistent with longitudinal worsening of lung disease. Multivariate analysis revealed baseline PS, baseline TS, and 1-year changes in BS and air trapping score were predictive of 2-year changes in BS. CONCLUSIONS: MPS and QATA1-A2 were the most sensitive indicators of progressive childhood CF lung disease. The 1-year change in the bronchiectasis score had the most positive predictive power for 2-year change in bronchiectasis.


Assuntos
Bronquiectasia/etiologia , Fibrose Cística/fisiopatologia , Progressão da Doença , Adolescente , Brônquios/anatomia & histologia , Brônquios/diagnóstico por imagem , Criança , Fibrose Cística/complicações , Fibrose Cística/diagnóstico , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Muco , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde , Radiografia Torácica , Sensibilidade e Especificidade , Espirometria , Tomografia Computadorizada por Raios X
12.
Top Magn Reson Imaging ; 18(5): 389-400, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18025993

RESUMO

OBJECTIVES: The aim of this article is to evaluate 3.0 T magnetic resonance imaging for characterization of vessel morphology and plaque composition. Emphasis is placed on early and moderate stages of carotid atherosclerosis, where increases in signal-to-noise (SNR) and contrast-to-noise (CNR) ratios compared with 1.5 T are sought. Comparison of in vivo 3.0 T imaging to histopathology is performed for validation. Parallel acceleration methods applied with an 8-channel carotid array are investigated as well as higher field ex vivo imaging to explore even further gains. The overall endeavor is to improve prospective assessment of atherosclerosis stage and stability for reduction of atherothrombotic event risk. METHODS: A total of 10 male and female subjects ranging in age from 22 to 72 years (5 healthy and 5 with cardiovascular disease) participated. Custom-built array coils were used with endogenous and exogenous multicontrast bright and black-blood protocols for 3.0 T carotid imaging. Comparisons were performed to 1.5 T, and ex vivo plaque was stained with hematoxylin and eosin for histology. Imaging (9.4 T) was also performed on intact specimens. RESULTS: The factor of 2 gain in signal-to-noise SNR is realized compared with 1.5 T along with improved wall-lumen and plaque component CNR. Post-contrast black-blood imaging within 5-10 minutes of gadolinium injection is optimal for detection of the necrotic lipid component. In a preliminary 18-month follow-up study, this method provided measurement of a 50% reduction in lipid content with minimal change in plaque size in a subject receiving aggressive statin therapy. Parallel imaging applied with signal averaging further improves 3.0 T black-blood vessel wall imaging. CONCLUSIONS: The use of 3.0 T for carotid plaque imaging has demonstrated increases in SNR and CNR compared with 1.5 T. Quantitative prospective studies of moderate and early plaques are feasible at 3.0 T. Continued improvements in coil arrays, 3-dimensional pulse sequences, and the use of novel molecular imaging agents implemented at high field will further improve magnetic resonance plaque characterization.


Assuntos
Estenose das Carótidas/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Estudos de Casos e Controles , Meios de Contraste , Desenho de Equipamento , Feminino , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade
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