Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.384
Filtrar
1.
NMR Biomed ; 34(1): e4420, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33021342

RESUMO

INTRODUCTION: Magnetic resonance elastography (MRE)-derived aortic stiffness is a potential biomarker for multiple cardiovascular diseases. Currently, gradient-recalled echo (GRE) MRE is a widely accepted technique to estimate aortic stiffness. However, multi-slice GRE MRE requires multiple breath-holds (BHs), which can be challenging for patients who cannot consistently hold their breath. The aim of this study was to investigate the feasibility of a multi-slice spin-echo echo-planar imaging (SE-EPI) MRE sequence for quantifying in vivo aortic stiffness using a free-breathing (FB) protocol and a single-BH protocol. METHOD: On Scanner 1, 25 healthy subjects participated in the validation of FB SE-EPI against FB GRE. On Scanner 2, another 15 healthy subjects were recruited to compare FB SE-EPI with single-BH SE-EPI. Among all volunteers, five participants were studied on both scanners to investigate the inter-scanner reproducibility of FB SE-EPI aortic MRE. Bland-Altman analysis, Lin's concordance correlation coefficient (LCCC) and coefficient of variation (COV) were evaluated. The phase-difference signal-to-noise ratios (PD SNR) were compared. RESULTS: Aortic MRE using FB SE-EPI and FB GRE yielded similar stiffnesses (paired t-test, P = 0.19), with LCCC = 0.97. The FB SE-EPI measurements were reproducible (intra-scanner LCCC = 0.96) and highly repeatable (LCCC = 0.99). The FB SE-EPI MRE was also reproducible across different scanners (inter-scanner LCCC = 0.96). Single-BH SE-EPI scans yielded similar stiffness to FB SE-EPI scans (LCCC = 0.99) and demonstrated a low COV of 2.67% across five repeated measurements. CONCLUSION: Multi-slice SE-EPI aortic MRE using an FB protocol or a single-BH protocol is reproducible and repeatable with advantage over multi-slice FB GRE in reducing acquisition time. Additionally, FB SE-EPI MRE provides a potential alternative to BH scans for patients who have challenges in holding their breath.


Assuntos
Aorta Abdominal/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca/métodos , Técnicas de Imagem por Elasticidade/métodos , Imagem por Ressonância Magnética/métodos , Rigidez Vascular , Aorta Abdominal/fisiologia , Técnicas de Imagem de Sincronização Cardíaca/instrumentação , Imagem Ecoplanar/instrumentação , Imagem Ecoplanar/métodos , Técnicas de Imagem por Elasticidade/instrumentação , Estudos de Viabilidade , Humanos , Imagem por Ressonância Magnética/instrumentação , Valores de Referência , Reprodutibilidade dos Testes , Respiração , Razão Sinal-Ruído
3.
Am J Cardiol ; 134: 99-107, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32917344

RESUMO

Heart failure (HF) is a leading cause of morbidity. Strategies for preventing HF are paramount. Prevalent extracoronary calcification is associated with HF risk but less is known about progression of mitral annular (MAC) and aortic valve calcification (AVC) and HF risk. Progression of valvular calcification (VC) [interval change of >0 units/yr] was assessed by 2 cardiac computed tomography scans over a median of 2.4 years. We used Cox regression to determine the risk of adjudicated HF and linear mixed effects models to determine 10-year change in left ventricular (LV) parameters measured by cardiac magnetic resonance imaging associated with VC progression. We studied 5,591 MESA participants free of baseline cardiovascular disease. Mean ± SD age was 62 ± 10 years; 53% women; 83% had no VC progression, 15% progressed at 1 site (AVC or MAC) and 3% at both sites. There were 251 incident HF over 15 years. After adjusting for cardiovascular risk factors, the hazard ratios (95% confidence interval) of HF associated with VC progression at 1 and 2 sites were 1.62 (1.21 to 2.17) and 1.88 (1.14 to 3.09), respectively, compared with no progression (p-for-trend <0.001). Hazard ratios were higher for HFpEF (2.52 [1.63 to 3.90] and 2.49 [1.19 to 5.25]) but nonsignificant for HFrEF. Both AVC (1.61 [1.19 to 2.19]) and MAC (1.50 [1.09 to 2.07]) progression were associated with HF. VC was associated with worsening of some LV parameters over 10 years. In conclusion, VC progression was associated with increased risk of HF and change in LV function. Interventions targeted at reducing VC progression may also impact HF risk, particularly HFpEF.


Assuntos
Valva Aórtica/diagnóstico por imagem , Calcinose/epidemiologia , Insuficiência Cardíaca/epidemiologia , Doenças das Valvas Cardíacas/epidemiologia , Ventrículos do Coração/diagnóstico por imagem , Valva Mitral/diagnóstico por imagem , Idoso , Calcinose/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca , Progressão da Doença , Feminino , Insuficiência Cardíaca/fisiopatologia , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Volume Sistólico , Tomografia Computadorizada por Raios X
4.
J Cardiovasc Magn Reson ; 22(1): 59, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32772927

RESUMO

BACKGROUND: Anatomically pre-shaped sinus prostheses (SP) were developed to mimic the aortic sinus with the goal to preserve near physiological hemodynamic conditions after valve-sparing aortic root replacement. Although SP have shown more physiological flow patterns, a comparison to straight tube prosthesis and the analysis of derived quantitative parameters is lacking. Hence, this study sought to analyze differences in aortic wall shear stress (WSS) between anatomically pre-shaped SP, conventional straight tube prostheses (TP), and age-matched healthy subjects) using time-resolved 3-dimensional flow cardiovascular magnetic resonance (4D Flow CMR). Moreover, the WSS gradient was introduced and analyzed regarding its sensitivity to detect changes in hemodynamics and its dependency on the expression of secondary flow patterns. METHODS: Twelve patients with SP (12 male, 62 ± 9yr), eight patients with TP (6 male, 59 ± 9yr), and twelve healthy subjects (2 male, 55 ± 6yr) were examined at 3 T with a 4D Flow CMR sequence in this case control study. Six analysis planes were placed in the thoracic aorta at reproducible landmarks. The following WSS parameters were recorded: WSSavg (spatially averaged over the contour at peak systole), max. WSSseg (maximum segmental WSS), min. WSSseg (minimum segmental WSS) and the WSS Gradient, calculated as max. WSSseg - min. WSSseg. Kruskal-Wallis- and Mann-Whitney-U-Test were used for statistical comparison of groups. Occurrence and expression of secondary flow patterns were evaluated and correlated to WSS values using Spearman's correlation coefficient. RESULTS: In the planes bordering the prosthesis all WSS values were significantly lower in the SP compared to the TP, approaching the physiological optimum of the healthy subjects. The WSS gradient showed significantly different values in the four proximally localized contours when comparing both prostheses with healthy subjects. Strong correlations between an elevated WSS gradient and secondary flow patterns were found in the ascending aorta and the aortic arch. CONCLUSION: Overall, the SP has a positive impact on WSS, most pronounced at the site and adjacent to the prosthesis. The WSS gradient differed most obviously and the correlation of the WSS gradient with the occurrence of secondary flow patterns provides further evidence for linking disturbed flow, which was markedly increased in patients compared to healthy sub jects, to degenerative remodeling of the vascular wall.


Assuntos
Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Valva Aórtica/diagnóstico por imagem , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Hemodinâmica , Imagem por Ressonância Magnética , Imagem de Perfusão/métodos , Desenho de Prótese , Adulto , Idoso , Aorta Torácica/fisiopatologia , Valva Aórtica/fisiopatologia , Técnicas de Imagem de Sincronização Cardíaca , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Estresse Mecânico , Resultado do Tratamento
5.
Ann Vasc Surg ; 69: 400-412, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738387

RESUMO

BACKGROUND: To examine intraheartbeat displacements (IHD) and geometrical changes of endografts for abdominal aortic aneurysm repair over the course of years, defined as follow-up displacements (FUD), and to correlate them with computational fluid dynamics (CFD). Despite the widespread use of endovascular aneurysm repair (EVAR), we still know little about endograft behavior after deployment. METHODS: Two cases, treated with either expanded polytetrafluoroethylene on a nitinol stent frame (PI) or with woven polyester fabric sutured to a stainless-steel Z stent skeleton (PII), were submitted to dynamic computed tomography angiography at 1, 12, and 60 months after implantation. After segmentation, IHD were computed as displacements of the reconstructed surface with respect to the diastolic instant. Similarly, FUD were studied using imaging techniques that align temporal successive segmentations. In addition, numerical simulations for blood dynamics were performed to compute viscous forces, specifically wall shear stress and time-averaged wall shear stress (TAWSS). RESULTS: IHD analysis showed slight translations without deformation for the PI endograft with respect to the stiffer stainless-steel endograft behavior of PII. FUD showed in PI motion of the metallic struts mainly focused on the distal main body of the endograft and in the zone overlapping with iliac branches. In PII, we observed a huge FUD in the middle and inferior-anterior regions of the main body. CFD analysis revealed changes of velocity patterns associated with remodeling of the iliac zone for PI and of the main body region for PII, where flow impinges the lumen wall and progressively induces deformation of the endograft wires. Measurement of TAWSS demonstrated flow disturbances in the enlarged region correlated with displacement analysis. CONCLUSIONS: Image-based displacement analysis associated with CFD enabled very subtle evaluations of endograft behavior on different temporal scales. This kind of study could be helpful both for physicians, forecasting evolution during the life span of the endograft, and manufacturers, giving them useful information about endograft implant performance and design.


Assuntos
Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Técnicas de Imagem de Sincronização Cardíaca , Procedimentos Endovasculares/instrumentação , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Stents , Idoso , Ligas , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/fisiopatologia , Aortografia , Angiografia por Tomografia Computadorizada , Eletrocardiografia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Poliésteres , Politetrafluoretileno , Valor Preditivo dos Testes , Desenho de Prótese , Fluxo Sanguíneo Regional , Aço Inoxidável , Estresse Mecânico , Fatores de Tempo , Resultado do Tratamento
6.
J Cardiovasc Magn Reson ; 22(1): 54, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32713347

RESUMO

BACKGROUND: Although the breath-hold cine balanced steady state free precession (bSSFP) imaging is well established for assessment of biventricular volumes and function, shorter breath-hold times or no breath-holds are beneficial in children and severely ill or sedated patients. METHODS: Clinical cardiovascular magnetic resonance (CMR) examinations from September 2019 to October 2019 that included breath-hold (BH) and free-breathing (FB) cine bSSFP imaging accelerated using compressed sensitivity encoding (C-SENSE) factor of 3 in addition to the clinical standard BH cine bSSFP imaging using SENSE factor of 2 were analyzed retrospectively. Patients with structurally normal hearts who could perform consistent BHs were included. Aortic flow measured by phase contrast acquisition was used as a reference for the left ventricular (LV) stroke volume. Comparative analysis was performed for evaluation of biventricular volumes and function, imaging times, quantitative image quality, and qualitative image scoring. RESULTS: There were 26 patients who underwent all three cine scans during the study period (16.7 ± 6.4 years, body surface area (BSA) 1.6 ± 0.4 m2, heart rate 83 ± 7 beats/min). BH durations of 8 ± 1 s with C-SENSE = 3 were significantly shorter (p < 0.001) by 33% compared to 12 ± 1 s with SENSE = 2. Actual scan time for BH SENSE (4.9 ± 1.2 min) was comparable to that with FB C-SENSE (5.2 ± 1.5 min; p= NS). Biventricular stroke volume and ejection fraction, and LV mass computed using all three sequences were comparable. There was a small but statistically significant (p < 0.05) difference in LV end-diastolic volume (- 3.0 ± 6.8 ml) between BH SENSE and FB C-SENSE. There was a small but statistically significant (p < 0.005) difference in end-diastolic LV (- 5.0 ± 7.7 ml) and RV (- 6.0 ± 8.5 ml) volume and end-systolic LV (- 3.2 ± 4.3 ml) and RV(- 4.2 ± 6.8 ml) volumes between BH C-SENSE and FB C-SENSE. The LV stroke volumes from all three sequences had excellent correlations (r = 0.96, slope = 0.98-1.02) with aortic flow, with overestimation by 2.7 (5%) to 4.6 (8%) ml/beat. The image quality score was Excellent (16 of 26) to Good (10 of 26) with BH SENSE, Excellent (13 of 26) to Good (13 of 26) with BH C-SENSE, and Excellent (3 of 26) to Good (21 of 26) to Adequate (2 of 26) with FB C-SENSE. CONCLUSIONS: Image quality and ventricular volumetric and functional indices using either BH or FB C-SENSE cine bSSFP imaging were comparable to standard BH SENSE cine bSSFP imaging while maintaining nominally identical spatio-temporal resolution. This accelerated image acquisition provides an alternative to accommodate patients with impaired BH capacity.


Assuntos
Suspensão da Respiração , Cardiopatias/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética , Volume Sistólico , Função Ventricular Esquerda , Função Ventricular Direita , Adolescente , Adulto , Fatores Etários , Técnicas de Imagem de Sincronização Cardíaca , Criança , Feminino , Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
7.
J Cardiovasc Magn Reson ; 22(1): 53, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32684167

RESUMO

BACKGROUND: Conventional 2D inversion recovery (IR) and phase sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) have been widely incorporated into routine CMR for the assessment of myocardial viability. However, reliable suppression of fat signal, and increased isotropic spatial resolution and volumetric coverage within a clinically feasible scan time remain a challenge. In order to address these challenges, this work proposes a highly efficient respiratory motion-corrected 3D whole-heart water/fat LGE imaging framework. METHODS: An accelerated IR-prepared 3D dual-echo acquisition and motion-corrected reconstruction framework for whole-heart water/fat LGE imaging was developed. The acquisition sequence includes 2D image navigators (iNAV), which are used to track the respiratory motion of the heart and enable 100% scan efficiency. Non-rigid motion information estimated from the 2D iNAVs and from the data itself is integrated into a high-dimensional patch-based undersampled reconstruction technique (HD-PROST), to produce high-resolution water/fat 3D LGE images. A cohort of 20 patients with known or suspected cardiovascular disease was scanned with the proposed 3D water/fat LGE approach. 3D water LGE images were compared to conventional breath-held 2D LGE images (2-chamber, 4-chamber and stack of short-axis views) in terms of image quality (1: full diagnostic to 4: non-diagnostic) and presence of LGE findings. RESULTS: Image quality was considered diagnostic in 18/20 datasets for both 2D and 3D LGE magnitude images, with comparable image quality scores (2D: 2.05 ± 0.72, 3D: 1.88 ± 0.90, p-value = 0.62) and overall agreement in LGE findings. Acquisition time for isotropic high-resolution (1.3mm3) water/fat LGE images was 8.0 ± 1.4 min (3-fold acceleration, 60-88 slices covering the whole heart), while 2D LGE images were acquired in 5.6 ± 2.2 min (12-18 slices, including pauses between breath-holds) albeit with a lower spatial resolution (1.40-1.75 mm in-plane × 8 mm slice thickness). CONCLUSION: A novel framework for motion-corrected whole-heart 3D water/fat LGE imaging has been introduced. The method was validated in patients with known or suspected cardiovascular disease, showing good agreement with conventional breath-held 2D LGE imaging, but offering higher spatial resolution, improved volumetric coverage and good image quality from a free-breathing acquisition with 100% scan efficiency and predictable scan time.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Adiposidade , Água Corporal/química , Doenças Cardiovasculares/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Coração/diagnóstico por imagem , Imageamento Tridimensional , Imagem por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Tecido Adiposo/fisiopatologia , Adulto , Idoso , Suspensão da Respiração , Técnicas de Imagem de Sincronização Cardíaca , Doenças Cardiovasculares/fisiopatologia , Eletrocardiografia , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
8.
J Surg Oncol ; 122(3): 407-411, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32483842

RESUMO

BACKGROUND AND OBJECTIVES: Irreversible electroporation (IRE) is a nonthermal electrical tumor ablative strategy for unresectable tumors. IRE is relatively safe around critical structures but may induce cardiac arrhythmia when its delivery is not synchronized to the cardiac cycle. We performed a systematic literature review to determine rates of arrhythmia when IRE was utilized with or without cardiac synchronization. METHODS: An online literature search was conducted with additional hand selection of articles. Data were extracted and pooled analyses were performed. RESULTS: Twelve articles were included in analysis. IRE was performed for 481 patients; 46% hepatic tumors (n = 223), 36% pancreatic lesions (n = 168), and multiple other locations including prostate. Synchronization was performed on 422 patients. Arrhythmias were noted in 3.7% of cases (n = 18/481); cardiac synchronization: 1.2% (n = 5/422) vs unsynchronized: 22.0% (n = 13/59), P < .0001. These events occurred in every organ except the prostate. CONCLUSIONS: IRE remains a potent technology for unresectable tumors, but arrhythmia is a clinical concern. This literature review confirms that cardiac gating should be used in all cases outside of prostate to prevent this potentially serious adverse event.


Assuntos
Técnicas de Ablação/estatística & dados numéricos , Arritmias Cardíacas/epidemiologia , Eletroporação/estatística & dados numéricos , Neoplasias Hepáticas/cirurgia , Neoplasias Pancreáticas/cirurgia , Técnicas de Ablação/efeitos adversos , Arritmias Cardíacas/diagnóstico por imagem , Arritmias Cardíacas/etiologia , Técnicas de Imagem de Sincronização Cardíaca/métodos , Humanos
9.
Int J Cardiovasc Imaging ; 36(9): 1791-1799, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32419092

RESUMO

The aim of this study was to investigate the image quality and radiation dose of different scanning protocols in dual-source CT cardiothoracic angiography for children with tetralogy of Fallot (TOF). Seventy-five consecutive children with known or suspected TOF were enrolled to undergo prospective ECG-triggering sequential dual-source CT (DSCT) cardiothoracic angiography. According to the scanning protocols, these patients were randomly divided into 3 groups: fixed delay time (FDT, n = 25, group A), automatic bolus-tracking (ABT, n = 25, group B) and manual bolus-tracking (MBT, n = 25, group C). Subjective and objective image quality were evaluated. The radiation doses were recorded. The image quality scores of group C were significantly higher than those of group A and B. The absolute value of difference (D-value) on CT attenuation between left (CTLV) and right ventricle (CTRV) in group C was significantly lower than that in group A and B. The total effective dose of groups A, B and C were 0.39 ± 0.06 mSv, 0.40 ± 0.07 mSv and 0.40 ± 0.08 mSv, respectively. There was no significant difference among 3 groups (P = 0.722). Scanning protocol has significantly impacts on the image quality of cardiovascular structures for TOF patients. Compared with the conventional scanning protocols FDT and ABT, the MBT technique provides high image quality and achieves more homogenous attenuation among different patients with TOF.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Doses de Radiação , Exposição à Radiação/prevenção & controle , Tetralogia de Fallot/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca , Angiografia por Tomografia Computadorizada/efeitos adversos , Meios de Contraste/administração & dosagem , Angiografia Coronária/efeitos adversos , Vasos Coronários/fisiopatologia , Eletrocardiografia , Feminino , Humanos , Lactente , Masculino , Tomografia Computadorizada Multidetectores/efeitos adversos , Variações Dependentes do Observador , Valor Preditivo dos Testes , Exposição à Radiação/efeitos adversos , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Tetralogia de Fallot/fisiopatologia
11.
Int J Cardiovasc Imaging ; 36(8): 1543-1550, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32328870

RESUMO

In patients with rheumatic mitral stenosis (MS), some previous studies have investigated the influence of balloon mitral valvuloplasty (BMV) on left ventricular (LV) systolic function. However, the impact of BMV on LV twisting motion in this clinical setting has not been studied before yet. To describe changes in LV torsion in patients with rheumatic MS following BMV. Thirty patients (median age 33 years, 22 women) with isolated severe MS were studied. CMR myocardial tissue tagging was used for assessment of LV rotational deformation. LV torsion was calculated as the twist value (the net difference between apical counterclockwise and basal clockwise rotation) normalized to the length of the ventricle and multiplied by the mean radius at the base and apex. All patients had CMR studies before, 6 months and 1 year after successful BMV. At baseline, patients had a mitral valve area of 0.9 (0.6-1.3) cm2, mean pressure gradient of 12.5 (8-24) mmHg across the valve as measured by transthoracic echocardiography. Median LV ejection fraction (LVEF) estimated by CMR was 57 (range: 45-69) %. A significant improvement in LV base-apex torsion was shown at 6 months (3.3° vs. 2.5°, p < 0.001) with a further improvement at 1 year (4.1° vs. 3.3°, p = 0.05). Similar pattern of change was seen in LV base-mid torsion with a significant increase at 6 months (3.6° vs. 2.3°, p < 0.001) and a further increase at 1 year (4.7° vs. 3.6°, p = 0.007). These changes were associated with a significant increase in LVEF (62% vs. 57%, p < 0.001) at 1 year following BMV. Successful BMV is associated with a significant improvement in LV torsion that is accompanied by a significant improvement in LVEF.


Assuntos
Valvuloplastia com Balão , Imagem Cinética por Ressonância Magnética , Estenose da Valva Mitral/terapia , Valva Mitral/diagnóstico por imagem , Cardiopatia Reumática/terapia , Volume Sistólico , Função Ventricular Esquerda , Adulto , Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Valva Mitral/fisiopatologia , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos , Recuperação de Função Fisiológica , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/fisiopatologia , Fatores de Tempo , Torção Mecânica , Resultado do Tratamento , Adulto Jovem
12.
Int J Cardiovasc Imaging ; 36(8): 1551-1557, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32306158

RESUMO

A fluoroscopic view perpendicular to the aortic valve annulus is required during transcatheter aortic valve implantation (TAVI) for obtaining an optimal deployment of the bioprosthesis. By predicting c-arm angulation, pre-procedural MDCT could decrease the number of aortograms, shorten the time of the procedure and reduce the amount of intra-arterial contrast agent. The aim of our study was to assess the accuracy of MDCT in predicting c-arm angulation at the cath. lab. In this single center study, we investigated MDCT prediction of c-arm angulation in patients having undergone a TAVI procedure using SAPIEN 3® (Edwards Lifesciences, USA). Prior to the procedure, an experienced radiologist had reported the angulation using dedicated software (CTreport). After the procedure, a blinded experienced radiologist retrospectively measured the angles using the same method (CTstudy). Interobserver variability was drawn from the comparison between CTreport and CTstudy. Then, the mean angular difference between the predicted MDCT angles (CTstudy) was compared to the working view recorded at the cath. lab. Seventy-nine patients (M/F = 0.65; mean age: 85.2 years ± 5.3) were included. Interobserver variability was 5.9 ± 6.1°. The mean absolute difference between MDCT and fluoroscopy was 8.8 ± 7.1°. The present study showed that MDCT could predict the coplanar fluoroscopic angles prior to TAVI using a balloon-expandable bioprosthesis Sapien 3® placed via a transfemoral approach with a mean angular difference of 8.8 ± 7.1°. Reproducibility was considered good as the mean difference between two independent measures was 5.9 ± 6.1°.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Tomografia Computadorizada Multidetectores , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Valvuloplastia com Balão , Bioprótese , Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Feminino , Próteses Valvulares Cardíacas , Hemodinâmica , Humanos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Desenho de Prótese , Reprodutibilidade dos Testes , Estudos Retrospectivos , Substituição da Valva Aórtica Transcateter/instrumentação
13.
Int J Cardiovasc Imaging ; 36(8): 1533-1542, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32314122

RESUMO

Aortic diameter measurements play a crucial role for the indication of aortic root surgery in Marfan patients. However, for magnetic resonance angiography (MRA)-derived measurements, there is no consensus on whether the aortic wall should be included or excluded in the aortic diameter. The purpose of this retrospective study was to compare the reliability of non-contrast bright blood MRA aortic inner-to-inner and outer-to-outer edge measurements in patients with Marfan syndrome. Forty Marfan patients underwent ECG-gated balanced steady-state free-precession MRA of the aorta at 1.5 T. Two readers independently performed inner and outer measurements at different aortic levels. They rated the image quality of the delineation of both inner and outer vessel wall edges on a four-point scale. MRA-derived diameters of the sinuses of Valsalva were compared with echocardiography-derived diameters. Aortic vessel wall delineation score was rated higher at all levels for inner than for outer vessel walls (p < 0.001). Inter- and intraobserver variances of aortic measurements were smaller for inner-to-inner measurements at the sinuses of Valsalva, sinotubular junction and ascending aorta (p < 0.03). There was a difference of 1.1 ± 2.3 mm for inner MRA measurements (p = 0.014) and 6.9 ± 3.1 mm for outer MRA measurements (p < 0.001) when compared to echocardiographic leading-edge measurements. Inner-to-inner vessel wall diameter measurements in non-contrast bright blood MRA provide more reliable diameters when compared to outer-to-outer vessel wall measurements of the aortic root. Therefore, we propose to rely on inner rather than outer aortic wall measurements in non-contrast-MRA when monitoring aortic diameters in patients with Marfan syndrome.


Assuntos
Aorta/diagnóstico por imagem , Aneurisma Aórtico/diagnóstico por imagem , Angiografia por Ressonância Magnética , Síndrome de Marfan/complicações , Seio Aórtico/diagnóstico por imagem , Adolescente , Adulto , Aorta/fisiopatologia , Aneurisma Aórtico/etiologia , Aneurisma Aórtico/fisiopatologia , Técnicas de Imagem de Sincronização Cardíaca , Dilatação Patológica , Eletrocardiografia , Feminino , Humanos , Masculino , Síndrome de Marfan/diagnóstico , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Seio Aórtico/fisiopatologia , Remodelação Vascular , Adulto Jovem
14.
Int J Cardiovasc Imaging ; 36(8): 1575-1581, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32335821

RESUMO

To investigate whether image reconstruction with iterative reconstruction (IR) affects aortic valve calcification (AVC) scoring and likelihood categorization of severe aortic stenosis (AS). In this IRB-approved retrospective study, we included 100 consecutive patients with AS (40 females; mean age 77 ± 10 years; age range: 36-99 years) undergoing CT prior to transcatheter aortic valve replacement. Non-enhanced, electrocardiography-gated CT of the heart was reconstructed with filtered back projection (FBP) and with advanced modeled IR at strength levels 1-5. AVC Agatston scores were calculated and gender-specific cut-off values for AS likelihood categorization were applied according to current European Society of Cardiology recommendations (from unlikely to very likely). Friedman test with post-hoc Bonferroni correction was applied to analyze interval- and ordinal-scaled data. Compared to FBP, each IR strength level produced significantly different AVC Agatston scores (p < 0.001-0.002). Median AVC Agatston score for image reconstruction with FBP was 2527 (IQR: 1711-3663) and decreased with increasing IR strength levels up to 2281 (IQR: 1471-3357) at strength level 5. Likelihood categorization of severe AS was significantly different among image reconstruction algorithms (p < 0.001). Image reconstruction with IR strength level 5 led to a downward shift of likelihood categorization in 28 patients (28%) compared to images reconstructed with FBP. IR significantly impacts AVC scoring with significantly decreasing AVC scores with increasing IR strength levels. This leads to relevant changes in likelihood categorization of patients with severe AS., leading to underestimation of severe AS.


Assuntos
Algoritmos , Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Calcinose/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Interpretação de Imagem Radiográfica Assistida por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Calcinose/fisiopatologia , Calcinose/cirurgia , Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Substituição da Valva Aórtica Transcateter
15.
Am J Med ; 133(10): e575-e583, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32268145

RESUMO

BACKGROUND: Coronary artery calcium (CAC) is a guideline recommended cardiovascular disease (CVD) risk stratification tool that increases with age and is associated with non-cardiovascular disease outcomes including cancer. We sought to define the age-specific change in the association between CAC and cause-specific mortality. METHODS: The Coronary Artery Calcium Consortium includes 59,502 asymptomatic patients age 40-75 without known CVD. Age-stratified mortality rates and parametric survival regression modeling was performed to estimate the age-specific CAC score at which CVD and cancer mortality risk were equal. RESULTS: The mean age was 54±8 years (67% men) and there were 2,423 deaths over a mean 12±3 years follow-up. Among individuals with CAC = 0, cancer was the leading cause of death, with low CVD mortality rates for both younger (40-54 years) 0.2/1,000 person-years and older participants (65-75 years) 1.3/1,000 person-years. When CAC ≥400, CVD was consistently the leading cause of death among younger (71% of deaths) and older participants (56% of deaths). The CAC score at which CVD overtook cancer as the leading cause of death increased exponentially with age and was approximately 115 at age 50 and 380 at age 65. CONCLUSIONS: Regardless of age, when CAC = 0 cancer was the leading cause of death and the cardiovascular disease mortality rate was low. Our age-specific estimate for the CAC score at which CVD overtakes cancer mortality allows for a more precise approach to synergistic prediction and prevention strategies for CVD and cancer.


Assuntos
Doenças Cardiovasculares/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Neoplasias/mortalidade , Calcificação Vascular/diagnóstico por imagem , Adulto , Idoso , Técnicas de Imagem de Sincronização Cardíaca , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
16.
Int J Cardiovasc Imaging ; 36(6): 1021-1029, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32112229

RESUMO

To quantify the impact of cardiac motion on stent length measurements with Optical Coherence Tomography (OCT) and to demonstrate in vivo OCT imaging of implanted stents, without motion artefacts. The study consists of: clinical data evaluation, simulations and in vivo tests. A comparison between OCT-measured and nominal stent lengths in 101 clinically acquired pullbacks was carried out, followed by a simulation of the effect of cardiac motion on stent length measurements, experimentally and computationally. Both a commercial system and a custom OCT, capable of completing a pullback between two consecutive ventricular contractions, were employed. A 13 mm long stent was implanted in the left anterior descending branch of two atherosclerotic swine and imaged with both OCT systems. The analysis of the clinical OCT images yielded an average difference of 1.1 ± 1.6 mm, with a maximum difference of 7.8 mm and the simulations replicated the statistics observed in clinical data. Imaging with the custom OCT, yielded an RMS error of 0.14 mm at 60 BPM with the start of the acquisition synchronized to the cardiac cycle. In vivo imaging with conventional OCT yielded a deviation of 1.2 mm, relative to the length measured on ex-vivo micro-CT, while the length measured in the pullback acquired by the custom OCT differed by 0.20 mm. We demonstrated motion artefact-free OCT-imaging of implanted stents, using ECG triggering and a rapid pullback.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Stents Farmacológicos , Eletrocardiografia , Frequência Cardíaca , Intervenção Coronária Percutânea/instrumentação , Tomografia de Coerência Óptica , Animais , Artefatos , Doença da Artéria Coronariana/fisiopatologia , Modelos Animais de Doenças , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sus scrofa
17.
Radiol Med ; 125(8): 706-714, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32206985

RESUMO

AIM: To examine the clinical and histopathological consequences of MRI in sheep implanted with non-MRI-conditional cardiac pacemakers. MATERIALS AND METHODS: Under general anesthesia, active fixation leads of two dual-chamber, non-MRI-conditional cardiac pacemakers (St. Jude Medical and Medtronic) were implanted either at the right ventricular apex or at the right atrium of two male sheep and connected to the V and A channels of the pacemakers, respectively. The generators were placed in cervical subcutaneous pockets. On day 5, both sheep underwent 1.5 T cervical and chest MRI with continuous electrocardiogram monitoring. Obtained sequences were T1-weighted (T1W), T2-weighted (T2W), T2-gradient echo and diffusion weighted (DW). The employed modes were OVO, VOO and VVI for one sheep and OAO, AOO and AAI for the other (unipolar and bipolar configuration of pacing and sensing for both). Battery impedance, pacing lead impedance, intrinsic amplitude and capture thresholds were checked at baseline and after each sequence, as well as 48 h after imaging. Histopathological examination of the cardiac tissue around the lead tip was performed 4 weeks post-imaging. RESULTS: No significant changes in device position or configuration were observed during or after MRI. Clinical outcome was uneventful in both sheep. Minor inflammatory and necrotic changes were reported after histopathological examination of the cardiac tissue around the lead tip. CONCLUSION: 1.5 T MRI of two implanted non-MRI-conditional pacemakers was found safe in terms of device configuration and stability, clinical outcome and cardiac tissue histopathological findings.


Assuntos
Segurança de Equipamentos , Imagem por Ressonância Magnética/métodos , Marca-Passo Artificial , Implantação de Prótese/métodos , Animais , Técnicas de Imagem de Sincronização Cardíaca , Imagem de Difusão por Ressonância Magnética , Masculino , Necrose , Implantação de Prótese/efeitos adversos , Ovinos
18.
Int J Cardiovasc Imaging ; 36(4): 749-755, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32062711

RESUMO

The incidence of heart failure (HF) increases in patients with chronic kidney disease (CKD). Factors that could predict patients with CKD who are at high risk for developing HF should be identified. We analysed clinical parameters and stress/rest myocardial perfusion imaging (MPI) findings derived from 499 patients with CKD by the Japanese Assessment of Cardiac Events and Survival Study by Quantitative Gated SPECT 3 (J-ACCESS 3) to clarify predictors of new-onset HF. Forty-one patients with congestive HF in the J-ACCESS 3 database were followed up for three years. Multivariable Cox hazards models selected haemoglobin (hazard ratio [HR] 0.809; 95% confidence interval [CI] 0.679-0.964), summed stress score (HR 1.082; 95% CI 1.016-1.151) and left ventricular ejection fraction (HR 0.970; 95% CI 0.949-0.992) as independent predictors of new-onset HF. Haemoglobin combined with summed stress scores and ejection fraction had the greatest incremental prognostic value over any one or more combined factors (global χ2, 29.9). Anaemia, stress-induced myocardial ischaemia, and left ventricular contraction are independent predictors of risk of new-onset HF in patients with CKD. Stress/rest MPI provides additional information with which to identify patients with CKD at greater risk of new-onset HF.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Imagem de Perfusão do Miocárdio/métodos , Insuficiência Renal Crônica/epidemiologia , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Idoso de 80 Anos ou mais , Anemia/epidemiologia , Bases de Dados Factuais , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/mortalidade , Medição de Risco , Fatores de Risco , Fatores de Tempo , Função Ventricular Esquerda
19.
J Cardiovasc Magn Reson ; 22(1): 12, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32014001

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) T1ρ mapping can be used to detect ischemic or non-ischemic cardiomyopathy without the need of exogenous contrast agents. Current 2D myocardial T1ρ mapping requires multiple breath-holds and provides limited coverage. Respiratory gating by diaphragmatic navigation has recently been exploited to enable free-breathing 3D T1ρ mapping, which, however, has low acquisition efficiency and may result in unpredictable and long scan times. This study aims to develop a fast respiratory motion-compensated 3D whole-heart myocardial T1ρ mapping technique with high spatial resolution and predictable scan time. METHODS: The proposed electrocardiogram (ECG)-triggered T1ρ mapping sequence is performed under free-breathing using an undersampled variable-density 3D Cartesian sampling with spiral-like order. Preparation pulses with different T1ρ spin-lock times are employed to acquire multiple T1ρ-weighted images. A saturation prepulse is played at the start of each heartbeat to reset the magnetization before T1ρ preparation. Image navigators are employed to enable beat-to-beat 2D translational respiratory motion correction of the heart for each T1ρ-weighted dataset, after which, 3D translational registration is performed to align all T1ρ-weighted volumes. Undersampled reconstruction is performed using a multi-contrast 3D patch-based low-rank algorithm. The accuracy of the proposed technique was tested in phantoms and in vivo in 11 healthy subjects in comparison with 2D T1ρ mapping. The feasibility of the proposed technique was further investigated in 3 patients with suspected cardiovascular disease. Breath-hold late-gadolinium enhanced (LGE) images were acquired in patients as reference for scar detection. RESULTS: Phantoms results revealed that the proposed technique provided accurate T1ρ values over a wide range of simulated heart rates in comparison to a 2D T1ρ mapping reference. Homogeneous 3D T1ρ maps were obtained for healthy subjects, with septal T1ρ of 58.0 ± 4.1 ms which was comparable to 2D breath-hold measurements (57.6 ± 4.7 ms, P = 0.83). Myocardial scar was detected in 1 of the 3 patients, and increased T1ρ values (87.4 ± 5.7 ms) were observed in the infarcted region. CONCLUSIONS: An accelerated free-breathing 3D whole-heart T1ρ mapping technique was developed with high respiratory scan efficiency and near-isotropic spatial resolution (1.7 × 1.7 × 2 mm3) in a clinically feasible scan time of ~ 6 mins. Preliminary patient results suggest that the proposed technique may find applications in non-contrast myocardial tissue characterization.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Frequência Cardíaca , Imageamento Tridimensional , Imagem por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio/patologia , Respiração , Adulto , Algoritmos , Técnicas de Imagem de Sincronização Cardíaca/instrumentação , Estudos de Viabilidade , Feminino , Humanos , Imagem por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Imagens de Fantasmas , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
20.
Circ J ; 84(4): 601-608, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32074543

RESUMO

BACKGROUND: Although coronary computed tomography angiography (CTA) is frequently used for identifying coronary artery disease, no studies have investigated the radiation dose in detail in Japan. The aim of this study was to estimate the radiation dose of coronary CTA in Japanese clinical practice and to identify the independent predictors associated with radiation dose.Methods and Results:A multicenter, retrospective, observational study (54 institutions) was conducted for estimating the radiation dose of coronary CTA in 2,469 patients between January and December 2013. Independent predictors associated with radiation dose were investigated on linear regression analysis. Median dose-length product (DLP) was 809.0 mGy·cm (IQR, 350.0-1,368.8 mGy·cm), corresponding to an estimated radiation dose of 11 mSv. The DLP per site significantly differed between institutions (median DLP per site, 92-2,131 mGy·cm; P<0.05). Independent predictors associated with radiation dose on multivariable linear regression were body weight, heart rate, non-stable sinus rhythm, scan length, tube voltage setting, electrocardiogram (ECG)-gated scanning protocol, and the image reconstruction technique (P<0.05 each). CONCLUSIONS: The coronary CTA radiation dose was relatively high in 2013, and it varied significantly between institutions. Effective strategies for radiation dose reduction were low tube voltage ≤100 kVp, retrospective ECG-gated scanning with dose modulation technique, prospective ECG-gated scanning, and the iterative reconstruction technique.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Doses de Radiação , Exposição à Radiação , Idoso , Técnicas de Imagem de Sincronização Cardíaca , Angiografia por Tomografia Computadorizada/efeitos adversos , Angiografia Coronária/efeitos adversos , Eletrocardiografia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/efeitos adversos , Valor Preditivo dos Testes , Exposição à Radiação/efeitos adversos , Exposição à Radiação/prevenção & controle , Sistema de Registros , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...