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1.
Cardiovasc Diabetol ; 23(1): 197, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849829

RESUMO

OBJECTIVE: Sodium glucose cotransporter 2 (SGLT2) inhibitors significantly improve cardiovascular outcomes in diabetic patients; however, the mechanism is unclear. We hypothesized that dapagliflozin improves cardiac outcomes via beneficial effects on systemic and cardiac inflammation and cardiac fibrosis. RESEARCH AND DESIGN METHODS: This randomized placebo-controlled clinical trial enrolled 62 adult patients (mean age 62, 17% female) with type 2 diabetes (T2D) without known heart failure. Subjects were randomized to 12 months of daily 10 mg dapagliflozin or placebo. For all patients, blood/plasma samples and cardiac magnetic resonance imaging (CMRI) were obtained at time of randomization and at the end of 12 months. Systemic inflammation was assessed by plasma IL-1B, TNFα, IL-6 and ketone levels and PBMC mitochondrial respiration, an emerging marker of sterile inflammation. Global myocardial strain was assessed by feature tracking; cardiac fibrosis was assessed by T1 mapping to calculate extracellular volume fraction (ECV); and cardiac tissue inflammation was assessed by T2 mapping. RESULTS: Between the baseline and 12-month time point, plasma IL-1B was reduced (- 1.8 pg/mL, P = 0.003) while ketones were increased (0.26 mM, P = 0.0001) in patients randomized to dapagliflozin. PBMC maximal oxygen consumption rate (OCR) decreased over the 12-month period in the placebo group but did not change in patients receiving dapagliflozin (- 158.9 pmole/min/106 cells, P = 0.0497 vs. - 5.2 pmole/min/106 cells, P = 0.41), a finding consistent with an anti-inflammatory effect of SGLT2i. Global myocardial strain, ECV and T2 relaxation time did not change in both study groups. GOV REGISTRATION: NCT03782259.


Assuntos
Compostos Benzidrílicos , Biomarcadores , Diabetes Mellitus Tipo 2 , Glucosídeos , Mediadores da Inflamação , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Compostos Benzidrílicos/uso terapêutico , Compostos Benzidrílicos/efeitos adversos , Glucosídeos/uso terapêutico , Glucosídeos/efeitos adversos , Feminino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Masculino , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Mediadores da Inflamação/sangue , Biomarcadores/sangue , Fatores de Tempo , Anti-Inflamatórios/uso terapêutico , Fibrose , Inflamação/tratamento farmacológico , Inflamação/sangue , Inflamação/diagnóstico , Método Duplo-Cego , Miocárdio/patologia , Miocárdio/metabolismo , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/diagnóstico por imagem , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/sangue
2.
J Magn Reson Imaging ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263621

RESUMO

BACKGROUND: Hypertension-induced impairment of the cerebral artery network contributes to cognitive impairment. Characterizing the structure and function of cerebral arteries may facilitate the understanding of hypertension-related pathological mechanisms and lead to the development of new indicators for cognitive impairment. PURPOSE: To investigate the associations between morphological features of the intracranial arteries distal to the circle of Willis on time-of-flight MRA (TOF-MRA) and cognitive performance in a hypertensive cohort. STUDY TYPE: Prospective observational study. POPULATION: 189 hypertensive older males (mean age 64.9 ± 7.2 years). FIELD STRENGTH/SEQUENCE: TOF-MRA sequence with a 3D spoiled gradient echo readout and arterial spin labeling perfusion imaging sequence with a 3D stack-of-spirals fast spin echo readout at 3T. ASSESSMENT: The intracranial arteries were segmented from TOF-MRA and the total length of distal arteries (TLoDA) and number of arterial branches (NoB) were calculated. The mean gray matter cerebral blood flow (GM-CBF) was extracted from arterial spin labeling perfusion imaging. The cognitive level was assessed with short-term and long-term delay-recall auditory verbal learning test (AVLT) scores, and with montreal cognitive assessment. STATISTICAL TESTS: Univariable and multivariable linear regression were used to analyze the associations between TLoDA, NoB, GM-CBF and the cognitive assessment scores, with P < 0.05 indicating significance. RESULTS: TLoDA (r = 0.314) and NoB (r = 0.346) were significantly correlated with GM-CBF. Multivariable linear regression analyses showed that TLoDA and NoB, but not GM-CBF (P = 0.272 and 0.141), were significantly associated with short-term and long-term delay-recall AVLT scores. These associations remained significant after adjusting for GM-CBF. DATA CONCLUSION: The TLoDA and NoB of distal intracranial arteries on TOF-MRA are significantly associated with cognitive impairment in hypertensive subjects. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.

3.
J Magn Reson Imaging ; 60(3): 889-899, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38131254

RESUMO

BACKGROUND: Progression of intracranial atherosclerotic disease (ICAD) is associated with ischemic stroke events and can be quantified with three-dimensional (3D) intracranial vessel wall (IVW) MRI. However, longitudinal 3D IVW studies are limited and ICAD evolution remains relatively unknown. PURPOSE: To evaluate ICAD changes longitudinally and to characterize the imaging patterns of atherosclerotic plaque evolution. STUDY TYPE: Prospective. POPULATION: 37 patients (69 ± 12 years old, 12 females) with angiography confirmed ICAD. FIELD STRENGTH/SEQUENCE: 3.0T/3D time-of-flight gradient echo sequence and T1- and proton density-weighted fast spin echo sequences. ASSESSMENT: Each patient underwent baseline and 1-year follow-up IVW. Then, IVW data from both time points were jointly preprocessed using a multitime point, multicontrast, and multiplanar viewing workflow (known as MOCHA). Lumen and outer wall of plaques were traced and measured, and plaques were then categorized into progression, stable, and regression groups based on changes in plaque wall thickness. Patient demographic and clinical data were collected. Culprit plaques were identified based on cerebral ischemic infarcts. STATISTICAL TESTS: Generalized estimating equations-based linear and logistic regressions were used to assess associations between vascular risk factors, medications, luminal stenosis, IVW plaque imaging features, and longitudinal changes. A two-sided P-value<0.05 was considered statistically significant. RESULTS: Diabetes was significantly associated with ICAD progression, resulting in 6.6% decrease in lumen area and 6.7% increase in wall thickness at 1-year follow-up. After accounting for arterial segments, baseline contrast enhancement predicted plaque progression (odds ratio = 3.61). Culprit plaques experienced an average luminal expansion of 10.9% after 1 year. 74% of the plaques remained stable during follow-up. The regression group (18 plaques) showed significant increase in minimum lumen area (from 7.4 to 8.3 mm2), while the progression group (13 plaques) showed significant decrease in minimum lumen area (from 5.4 to 4.3 mm2). DATA CONCLUSION: Longitudinal 3D IVW showed ICAD remodeling on the lumen side. Culprit plaques demonstrated longitudinal luminal expansion compared with their non-culprit counterparts. Baseline plaque contrast enhancement and diabetes mellitus were found to be significantly associated with ICAD changes. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.


Assuntos
Progressão da Doença , Arteriosclerose Intracraniana , Imageamento por Ressonância Magnética , Placa Aterosclerótica , Humanos , Feminino , Masculino , Estudos Prospectivos , Idoso , Placa Aterosclerótica/diagnóstico por imagem , Arteriosclerose Intracraniana/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Artérias Cerebrais/diagnóstico por imagem , Imageamento Tridimensional , Angiografia por Ressonância Magnética/métodos , Remodelação Vascular , Idoso de 80 Anos ou mais
5.
Artigo em Inglês | MEDLINE | ID: mdl-39038956

RESUMO

BACKGROUND AND PURPOSE: Accelerated and blood-suppressed post-contrast 3D intracranial vessel wall MRI (IVW) enables high-resolution rapid scanning but is associated with low SNR. We hypothesized that a deep-learning (DL) denoising algorithm applied to accelerated, blood-suppressed post-contrast IVW can yield high-quality images with reduced artifacts and higher SNR in shorter scan times. MATERIALS AND METHODS: Sixty-four consecutive patients underwent IVW, including conventional post-contrast 3D T1-sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) and delay-alternating with nutation for tailored excitation (DANTE) blood-suppressed and CAIPIRINHIA-accelerated (CAIPI) 3D T1-weighted TSE post-contrast sequences (DANTE-CAIPI-SPACE). DANTE-CAIPI-SPACE acquisitions were then denoised using an unrolled deep convolutional network (DANTECAIPI-SPACE+DL). SPACE, DANTE-CAIPI-SPACE, and DANTE-CAIPI-SPACE+DL images were compared for overall image quality, SNR, severity of artifacts, arterial and venous suppression, and lesion assessment using 4-point or 5-point Likert scales. Quantitative evaluation of SNR and contrast-to-noise ratio (CNR) was performed. RESULTS: DANTE-CAIPI-SPACE+DL showed significantly reduced arterial (1 [1-1.75] vs. 3 [3-4], p<0.001) and venous flow artifacts (1 [1-2] vs. 3 [3-4], p<0.001) compared to SPACE. There was no significant difference between DANTE-CAIPI-SPACE+DL and SPACE in terms of image quality, SNR, artifact ratings and lesion assessment. For SNR ratings, DANTE-CAIPI-SPACE+DL was significantly better compared to DANTE-CAIPI-SPACE (2 [1-2], vs. 3 [2-3], p<0.001). No statistically significant differences were found between DANTECAIPI-SPACE and DANTE-CAIPI-SPACE+DL for image quality, artifact, arterial blood and venous blood flow artifacts, and lesion assessment. Quantitative vessel wall SNR and CNR median values were significantly higher for DANTE-CAIPI-SPACE+DL (SNR: 9.71, CNR: 4.24) compared to DANTE-CAIPI-SPACE (SNR: 5.50, CNR: 2.64), (p<0.001 for each), but there was no significant difference between SPACE (SNR: 10.82, CNR: 5.21) and DANTE-CAIPI-SPACE+DL. CONCLUSIONS: Deep-learning denoised post-contrast T1-weighted DANTE-CAIPI-SPACE accelerated and blood-suppressed IVW showed improved flow suppression with a shorter scan time and equivalent qualitative and quantitative SNR measures relative to conventional post-contrast IVW. It also improved SNR metrics relative to post-contrast DANTE-CAIPI-SPACE IVW. Implementing deep-learning denoised DANTE-CAIPI-SPACE IVW has the potential to shorten protocol time while maintaining or improving the image quality of IVW. ABBREVIATIONS: DL=deep learning; IVW=Intracranial vessel wall MRI; SPACE=sampling perfection with application-optimized contrasts by using different flip angle evolution; DANTE=delay-alternating with nutation for tailored excitation; CAIPI=controlled aliasing in parallel imaging; CNR=contrast-to-noise ratio.

6.
Res Sq ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38585865

RESUMO

Objective: Sodium glucose cotransporter 2 (SGLT2) inhibitors significantly improve cardiovascular outcomes in diabetic patients; however, the mechanism is unclear. We hypothesized that dapagliflozin improves cardiac outcomes via beneficial effects on systemic and cardiac inflammation and cardiac fibrosis. Research and Design Methods: This randomized placebo-controlled clinical trial enrolled 62 adult patients (mean age 62, 17% female) with type 2 diabetes (T2D) without known heart failure. Subjects were randomized to 12 months of daily 10 mg dapagliflozin or placebo. For all patients, blood/plasma samples and cardiac magnetic resonance imaging (CMRI) were obtained at time of randomization and at the end of 12 months. Systemic inflammation was assessed by plasma IL-1B, TNFα, IL-6 and ketone levels and PBMC mitochondrial respiration, an emerging marker of sterile inflammation. Cardiac fibrosis was assessed by T1 mapping to calculate extracellular volume fraction (ECV); cardiac tissue inflammation was assessed by T2 mapping. Results: Between the baseline and 12-month time point, plasma IL-1B was reduced (-1.8 pg/mL, P=0.003) while ketones were increased (0.26 mM, P=0.0001) in patients randomized to dapagliflozin. PBMC maximal oxygen consumption rate (OCR) decreased over the 12-month period in the placebo group but did not change in patients receiving dapagliflozin (-158.9 pmole/min/106cells, P=0.0497 vs -45.2 pmole/min/106cells, P=0.41), a finding consistent with an anti-inflammatory effect of SGLT2i. ECV and T2 relaxation time did not change in both study groups. Conclusion: This study demonstrates that 12 months of dapagliflozin reduces IL-1B mediated systemic inflammation but affect cardiac fibrosis in T2D. Clinical Trialgov Registration: NCT03782259.

7.
Eur J Radiol ; 178: 111647, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39068857

RESUMO

PURPOSE: Intraplaque haemorrhage (IPH) is a well-known risk factor for faster plaque progression (volume increase); however, its etiology is unclear. We aimed at determining what other local plaque- and systemic factors contribute to plaque progression and to the development and progression of IPH. METHODS: We examined 98 asymptomatic participants with carotid plaque using serial multi-contrast magnetic resonance imaging. We measured the percent of wall volume (%WV=100 x [wall volume] / [total vessel volume]) and measured IPH and calcification volumes. We used generalized estimating equations-based regression to analyze predictors of %WV change and new IPH while accounting for covariates (sex, age and statin use), and multiple non-independent observations per participant. RESULTS: Total follow-up was 1.8 ± 0.8 years on average. The presence of IPH (ß: 0.6 %/y, p = 0.033) and calcification (ß: 1.2 %/y, p = 0.028) were each associated with faster plaque progression. New IPH, detected on a subsequent scan in 4 % of arteries that did not initially have IPH, was associated with larger calcification (odds ratio [OR]: 2.6 per 1-SD increase, p = 0.038) and higher pulse pressure (OR: 2.3 per 1-SD increase, p = 0.016). Larger calcification was associated with greater increases in pulse pressure (ß: 1.4 mm Hg/y per 1-SD increase, p = 0.040). CONCLUSIONS: IPH and calcification are each independently associated with faster plaque progression. The association of carotid calcification to increased pulse pressure and new IPH development suggests a possible mechanism by which calcification drives IPH development and plaque progression.


Assuntos
Pressão Sanguínea , Doenças das Artérias Carótidas , Hemorragia , Humanos , Masculino , Feminino , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/fisiopatologia , Idoso , Pessoa de Meia-Idade , Hemorragia/diagnóstico por imagem , Hemorragia/fisiopatologia , Progressão da Doença , Fatores de Risco , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/fisiopatologia , Calcificação Vascular/complicações , Placa Aterosclerótica/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Imageamento por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética
8.
Artigo em Inglês | MEDLINE | ID: mdl-38789121

RESUMO

BACKGROUND AND PURPOSE: The Circle of Willis (COW) is a crucial mechanism for cerebral collateral circulation. This proof-ofconcept study aims to develop and assess an analysis method to characterize the hemodynamics of the arterial segments in COW using arterial spin labeling (ASL) based non-contrast enhanced dynamic magnetic resonance angiography (dMRA). MATERIALS AND METHODS: The developed analysis method uses a graph model, bootstrap strategy, and ensemble learning methodologies to determine the time-curve shift from ASL dMRA to estimate the flow direction within the COW. The performance of the method was assessed on 52 subjects, using the flow direction, either antegrade or retrograde, derived from 3D phase contrast (PC) MRI as the reference. RESULTS: A total of 340 arterial segments in COW were evaluated, among which 30 (8.8%) had retrograde flow according to 3D PC. The ASL dMRA-based flow direction estimation has an accuracy, sensitivity, and specificity of 95.47%, 80%, and 96.34%, respectively. CONCLUSIONS: Using ASL dMRA and the developed image analysis method to estimate the flow direction in COW is feasible. This study provides a new method to assess the hemodynamics of the COW, which could be useful for the diagnosis and study of cerebrovascular diseases. ABBREVIATIONS: COW = Circle of Willis; ASL = arterial spin labeling; dMRA =dynamic magnetic resonance angiography; PC = phase contrast.

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