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1.
Artigo em Inglês | MEDLINE | ID: mdl-34780012

RESUMO

To evaluate the accuracy of coronary artery calcium (CAC) scoring at various tube voltages and different monoenergetic image reconstructions on a first-generation dual-source photon-counting detector CT (PCD-CT). A commercially available anthropomorphic chest phantom with calcium inserts was scanned at different tube voltages (90 kV, Sn100kV, 120 kV, and Sn140kV) on a first-generation dual-source PCD-CT system with quantum technology using automatic exposure control with an image quality (IQ) level of 20. The same phantom was also scanned on a conventional energy-integrating detector CT (120 kV; weighted filtered back projection) for reference. Extension rings were used to emulate different patient sizes. Virtual monoenergetic images at 65 keV and 70 keV applying different levels of quantum iterative reconstruction (QIR) were reconstructed from the PCD-CT data sets. CAC scores were determined and compared to the reference. Radiation doses were noted. At an IQ level of 20, radiation doses ranged between 1.18 mGy and 4.64 mGy, depending on the tube voltage and phantom size. Imaging at 90 kV or Sn100kV was associated with a size-dependent radiation dose reduction between 23% and 48% compared to 120 kV. Tube voltage adapted image reconstructions with 65 keV and QIR 3 at 90 kV and with 70 keV and QIR 1 at Sn100kV allowed to calculate CAC scores comparable to conventional EID-CT scans with a percentage deviation of ≤ 5% for all phantom sizes. Our phantom study indicates that CAC scoring with dual-source PCD-CT is accurate at various tube voltages, offering the possibility of substantial radiation dose reduction.

2.
Sci Rep ; 11(1): 12376, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117271

RESUMO

Cardiac magnetic resonance imaging (MRI) with late gadolinium enhancement (LGE) is considered the gold standard for scar detection after myocardial infarction. In times of increasing skepticism about gadolinium depositions in brain tissue and contraindications of gadolinium administration in some patient groups, tissue strain-based techniques for detecting ischemic scars should be further developed as part of clinical protocols. Therefore, the objective of the present work was to investigate whether segmental strain is noticeably affected in chronic infarcts and thus can be potentially used for infarct detection based on routinely acquired non-contrast cine images in patients with known coronary artery disease (CAD). Forty-six patients with known CAD and chronic scars in LGE images (5 female, mean age 52 ± 19 years) and 24 gender- and age-matched controls with normal cardiac MRI (2 female, mean age 47 ± 13 years) were retrospectively enrolled. Global (global peak circumferential [GPCS], global peak longitudinal [GPLS], global peak radial strain [GPRS]) and segmental (segmental peak circumferential [SPCS], segmental peak longitudinal [SPLS], segmental peak radial strain [SPRS]) strain parameters were calculated from standard non-contrast balanced SSFP cine sequences using commercially available software (Segment CMR, Medviso, Sweden). Visual wall motion assessment of short axis cine images as well as segmental circumferential strain calculations (endo-/epicardially contoured short axis cine and resulting polar plot strain map) of every patient and control were presented in random order to two independent blinded readers, which should localize potentially infarcted segments in those datasets blinded to LGE images and patient information. Global strain values were impaired in patients compared to controls (GPCS p = 0.02; GPLS p = 0.04; GPRS p = 0.01). Patients with preserved ejection fraction showed also impeded GPCS compared to healthy individuals (p = 0.04). In patients, mean SPCS was significantly impaired in subendocardially (-  5.4% ± 2) and in transmurally infarcted segments (- 1.2% ± 3) compared to remote myocardium (- 12.9% ± 3, p = 0.02 and 0.03, respectively). ROC analysis revealed an optimal cut-off value for SPCS for discriminating infarcted from remote myocardium of - 7.2% with a sensitivity of 89.4% and specificity of 85.7%. Mean SPRS was impeded in transmurally infarcted segments (15.9% ± 6) compared to SPRS of remote myocardium (31.4% ± 5; p = 0.02). The optimal cut-off value for SPRS for discriminating scar tissue from remote myocardium was 16.6% with a sensitivity of 83.3% and specificity of 76.5%. 80.3% of all in LGE infarcted segments (118/147) were correctly localized in segmental circumferential strain calculations based on non-contrast cine images compared to 53.7% (79/147) of infarcted segments detected by visual wall motion assessment (p > 0.01). Global strain parameters are impaired in patients with chronic infarcts compared to controls. Mean SPCS and SPRS in scar tissue is impeded compared to remote myocardium in infarcts patients. Blinded to LGE images, two readers correctly localized 80% of infarcted segments in segmental circumferential strain calculations based on non-contrast cine images, in contrast to only 54% of infarcted segments detected due to wall motion abnormalities in visual wall motion assessment. Analysis of segmental circumferential strain shows a promising method for detection of chronic scars in routinely acquired, non-contrast cine images for patients who cannot receive or decline gadolinium.


Assuntos
Cicatriz/patologia , Imagem Cinética por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Isquemia Miocárdica/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem
3.
Eur J Radiol Open ; 8: 100335, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33748350

RESUMO

OBJECTIVES: To determine with CT the prevalence and extent of mitral annular disjunction (MAD) in patients undergoing transcatheter aortic valve replacement (TAVR) and its association with mitral valve disease and arrhythmia. METHODS: We retrospectively evaluated 408 patients (median age, 82 years; 186 females) with severe aortic stenosis undergoing ECG-gated cardiac CT with end-systolic data acquisition. Baseline and follow-up data were collected in the context of a national registry. Two blinded, independent observers evaluated the presence of MAD on multi-planar reformations. Maximum MAD distance (left atrial wall-mitral leaflet junction to left ventricular myocardium) and circumferential extent of MAD were assessed on CT using dedicated post-processing software. Associated mitral valve disease was determined with echocardiography. RESULTS: 7.8 % (32/408) of patients with severe aortic stenosis had MAD. The maximum MAD was 3.5 mm (interquartile range: 3.0-4.0 mm). The circumferential extent of MAD comprised 34 ±â€¯15 % of the posterior and 26 ±â€¯12 % of the entire mitral annulus. Intra- and interobserver agreement for the detection of MAD on CT were excellent (kappa: 0.90 ±â€¯0.02 and 0.92 ±â€¯0.02). Mitral regurgitation (p = 1.00) and severe mitral annular calcification (p = 0.29) were similarly prevalent in MAD and non-MAD patients. Significantly more patients with MAD (6/32; 19 %) had mitral valve prolapse compared to those without (6/376; 2 %; p < 0.001). MAD was not associated with arrhythmia before and after TAVR (p > 0.05). CONCLUSIONS: Using CT, MAD was found in 7.8 % of patients with severe aortic stenosis, with a higher prevalence in patients with mitral valve prolapse. We found no association of MAD with arrhythmia before or after TAVR.

4.
J Cardiovasc Transl Res ; 14(4): 670-673, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32367345

RESUMO

International cardiovascular society recommendations to return to sports activities following acute myocarditis are based on expert consensus in the absence of prospective studies. We prospectively enrolled 30 patients with newly diagnosed myocarditis based on clinical parameters, laboratory measurements and cardiac magnetic resonance imaging with mildly reduced or preserved left ventricular ejection fraction (LVEF) with a follow-up of 12 months. Cessation of physical activity was recommended for 3 months. The average age was 35 (19-80) years with 73% male patients. One case of non-sustained ventricular tachycardia was recorded during 48-h-Holter electrocardiogram. Except for this case, all patients were allowed to resume physical exercise after 3 months. At 6- (n = 26) and 12-month (n = 19) follow-up neither cardiac events nor worsening LVEF were recorded. The risk of cardiac events at 1 year after diagnosis of myocarditis appears to be low after resumption of exercise after 3 months among patients who recover from acute myocarditis.


Assuntos
Ecocardiografia , Eletrocardiografia Ambulatorial , Teste de Esforço , Imageamento por Ressonância Magnética , Miocardite/diagnóstico , Volta ao Esporte , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/complicações , Miocardite/fisiopatologia , Projetos Piloto , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Recuperação de Função Fisiológica , Medição de Risco , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Função Ventricular Esquerda , Adulto Jovem
6.
J Cardiovasc Comput Tomogr ; 15(2): 161-166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32798185

RESUMO

PURPOSE: To determine the reliability of subjective and objective quantification of mitral annular calcification (MAC) in elderly patients with severe aortic stenosis, to define quantitative sex- and age-related reference values of MAC, and to correlate quantitative MAC with mitral valve disease. METHODS: In this retrospective, IRB-approved study, we included 559 patients (268 females, median age 81 years, inter-quartile range 77-85 years) with severe aortic stenosis undergoing CT. Four independent readers performed subjective MAC categorization as follows: no, mild, moderate, and severe MAC. Two independent readers performed quantitative evaluation of MAC using the Agatston score method (AgatstonMAC). Mitral valve disease was determined by echocardiography. RESULTS: Subjective MAC categorization showed high inter-reader agreement for no (k â€‹= â€‹0.88) and severe MAC (k â€‹= â€‹0.75), whereas agreement for moderate (k â€‹= â€‹0.59) and mild (k â€‹= â€‹0.45) MAC was moderate. Intra-reader agreement for subjective MAC categorization was substantial (k â€‹= â€‹0.69 and 0.62). Inter- and intra-reader agreement for AgatstonMAC were excellent (ICC â€‹= â€‹0.998 and 0.999, respectively), with minor inconsistencies in MAC involving the left ventricular outflow tract/aortic valve. There were significantly more women than men with MAC (n â€‹= â€‹227, 85% versus n â€‹= â€‹209, 72%; p â€‹< â€‹0.001), with a significantly higher AgatstonMAC (median 597, range 81-2055 versus median 244; range 0-1565; p â€‹< â€‹0.001), particularly in patients ≥85 years of age. AgatstonMAC showed an area-under-the-curve of 0.84 to diagnose mitral stenosis, whereas there was no association of AgatstonMAC with mitral regurgitation (p â€‹> â€‹0.05). CONCLUSIONS: Our study in elderly patients with severe aortic stenosis shows that quantitative MAC scoring is more reliable than subjective MAC assessment. Women show higher AgatstonMAC scores than men, particularly in the elderly population. AgatstonMAC shows high accuracy to diagnose mitral stenosis.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Calcinose/diagnóstico por imagem , Estenose da Valva Mitral/diagnóstico por imagem , Valva Mitral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Sistema de Registros , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores Sexuais
7.
Int J Cardiovasc Imaging ; 37(1): 305-313, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32793996

RESUMO

We compared a fast, single breath-hold three dimensional LGE sequence (3D LGE) with an established two dimensional multi breath-hold sequence (2D LGE) and evaluated image quality and the amount of myocardial fibrosis in patients with acute and chronic myocarditis. 3D LGE and 2D LGE (both spatial resolution 1.5 × 1.5 mm2, slice-thickness 8 mm, field of view 350 × 350 mm2) were acquired in 25 patients with acute myocarditis (mean age 40 ± 18 years, 7 female) and 27 patients with chronic myocarditis (mean age 44 ± 22 years, 9 female) on a 1.5 T MR system. Image quality was evaluated by two independent, blinded readers using a 5-point Likert scale. Total myocardial mass, fibrotic mass and total fibrotic tissue percentage were quantified for both sequences in both groups. There was no significant difference in image quality between 3D und 2D acquisitions in patients with acute (p = 0.8) and chronic (p = 0.5) myocarditis. No significant differences between 3D and 2D acquisitions could be shown for myocardial mass (acute p = 0.2; chronic p = 0.3), fibrous tissue mass (acute p = 0.7; chronic p = 0.1) and total fibrous percentage (acute p = 0.4 and chronic p = 0.2). Inter-observer agreement was substantial to almost perfect. Acquisition time was significantly shorter for 3D LGE (24 ± 5 s) as compared to 2D LGE (350 ± 58 s, p < 0.001). In patients with acute and chronic myocarditis 3D LGE imaging shows equal diagnostic quality compared to standard 2D LGE imaging but with significantly reduced acquisition time.


Assuntos
Meios de Contraste , Imageamento Tridimensional , Imagem Cinética por Ressonância Magnética , Miocardite/diagnóstico por imagem , Miocárdio/patologia , Compostos Organometálicos , Doença Aguda , Adolescente , Adulto , Idoso , Doença Crônica , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/patologia , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
8.
Int J Cardiol ; 310: 108-115, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31982162

RESUMO

BACKGROUND: Studies indicate no clear impact of intracoronary injection of bone-marrow unselected mononuclear cells (BM-MNC) after acute myocardial infarction (AMI) on left-ventricular function (LVEF). Strain parameters by cardiovascular magnetic resonance (CMR) have been proposed to be more sensitive to functional changes of the heart. The aim of the present study was to assess changes of global longitudinal (GLS) and circumferential strain (GCS) in a group of patients treated with BM-MNC after AMI. METHODS: One-hundred and forty-nine patients with successfully reperfused AMI and LV dysfunction (LVEF<45%) were retrospectively included into this sub-study of the SWISS-AMI multicentre trial. Patients were divided into control (N = 54), early (5-7 days after AMI, N = 51) and late BM-MNC treatment groups (3-4 weeks, N = 44). The endpoint was the change of GLS and GCS as obtained from cine sequences 4 and 12 months after AMI using feature tracking algorithm. RESULTS: In unadjusted analyses, the absolute change of GLS for the early treatment group from baseline to 4 months was 2.5 ± 4.3 (p < 0.01), to 12 months 2.7 ± 5.7% (p = 0.004). For late treatment, it was 1.5 ± 4.0% (p = 0.039, 4 months) and 2.5 ± 5.6% (p = 0.015, 12 months). For controls 0.7 ± 4.7% (p = 0.378), 0.8 ± 3.9% (p = 0.253) respectively. Adjusting for different baseline values, neither an overall treatment effect (both time-points) of BM-MNC nor a treatment time-related (only early or late) effect could be shown for all functional parameters. CONCLUSIONS: Among patients after AMI with successful reperfusion and LV dysfunction, intracoronary infusion of BM-MNC early or late after AMI did not improve global strain parameters at 4- or 12-months follow-up. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00355186.


Assuntos
Medula Óssea , Infarto do Miocárdio , Transplante de Medula Óssea , Humanos , Espectroscopia de Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/terapia , Estudos Retrospectivos , Resultado do Tratamento , Função Ventricular Esquerda
9.
Eur Radiol ; 28(10): 4111-4121, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29713770

RESUMO

OBJECTIVES: We aimed to assess the diagnostic performance of a combined protocol with coronary computed tomography angiography (CCTA) and stress CT perfusion imaging (CTP) in heart transplant patients for comprehensive morphological and functional imaging. METHODS: In this prospective study, 13 patients undergoing routine follow-up 8±6 years after heart transplantation underwent CCTA and dynamic adenosine stress CTP using a third-generation dual-source CT scanner, cardiac magnetic resonance (MR) adenosine stress perfusion imaging at 1.5 T, and catheter coronary angiography. In CCTA stenoses >50% luminal diameter narrowing were noted. Myocardial perfusion deficits were documented in CTP and MR. Quantitative myocardial blood flow (MBF) was calculated with CTP. Left ventricular ejection fraction was determined on cardiac MR cine images. Radiation doses of CT were determined. RESULTS: One of the 13 patients had to be excluded because of severe motion artifacts. CCTA identified three patients with stenosis >50%, which were confirmed with catheter coronary angiography. CTP showed four patients with stress-induced myocardial hypoperfusion, which were confirmed by MR stress perfusion imaging. Quantitative analysis of global MBF showed lower mean values as compared to known reference values (MBF under stress 125.5 ± 34.5 ml/100 ml/min). Average left ventricular ejection fraction was preserved (56 ± 5%). CONCLUSIONS: In heart transplant patients, a comprehensive CT protocol for the assessment of morphology and function including CCTA and CTP showed good concordance to results from MR perfusion imaging and catheter coronary angiography. KEY POINTS: • Stress CT perfusion imaging enables the detection of myocardial ischemia • CT myocardial perfusion imaging can be combined with coronary computed tomography angiography • Combining perfusion and coronary CT imaging is accurate in heart transplant patients • CT myocardial perfusion imaging can be performed at a reasonable radiation dose.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Transplante de Coração , Imagem de Perfusão do Miocárdio/métodos , Adulto , Idoso , Estenose Coronária/fisiopatologia , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
10.
Int J Cardiol ; 217: 167-73, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27183453

RESUMO

BACKGROUND: This study aims to determine whether the quantification of myocardial fibrosis in patients with Fabry disease (FD) and hypertrophic cardiomyopathy (HCM) using a late gadolinium enhancement (LGE) singlebreath-hold three-dimensional (3D) inversion recovery magnetic resonance (MR) imaging sequence is comparable with a clinically established two-dimensional (2D) multi-breath-hold sequence. METHODS: In this retrospective, IRB-approved study, 40 consecutive patients (18 male; mean age 50±17years) with Fabry disease (n=18) and HCM (n=22) underwent MR imaging at 1.5T. Spatial resolution was the same for 3D and 2D images (field-of-view, 350×350mm(2); in-plane-resolution, 1.2×1.2mm(2); section-thickness, 8mm). Datasets were analyzed for subjective image quality; myocardial and fibrotic mass, and total fibrotic tissue percentage were quantified. RESULTS: There was no significant difference in subjective image quality between 3D and 2D acquisitions (P=0.1 and P=0.3) for either disease. In patients with Fabry disease there were no significant differences between 3D and 2D acquisitions for myocardial mass (P=0.55), fibrous tissue mass (P=0.89), and total fibrous percentage (P=0.67), with good agreement between acquisitions according to Bland-Altman analyses. In patients with HCM there were also no significant differences between acquisitions for myocardial mass (P=0.48), fibrous tissue mass (P=0.56), and total fibrous percentage (P=0.67), with good agreement according to Bland-Altman analyses. Acquisition time was significantly shorter for 3D (25±5s) as compared to the 2D sequence (349±62s, P<0.001). CONCLUSIONS: In patients with Fabry disease and HCM, 3D LGE imaging provides equivalent diagnostic information in regard to quantification of myocardial fibrosis as compared with a standard 2D sequence, but at superior acquisition speed.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Doença de Fabry/diagnóstico por imagem , Gadolínio/metabolismo , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
11.
Herz ; 40 Suppl 3: 282-90, 2015 May.
Artigo em Alemão | MEDLINE | ID: mdl-25178875

RESUMO

Since the discovery of the obese (ob) gene product leptin, fat has been considered an endocrine organ. Especially epicardial fat has gained increasing attention in recent years. The epicardial fat plays a major role in fat metabolism; however, harmful properties have also been reported. Echocardiography, computed tomography and cardiac magnetic resonance imaging are the non-invasive tools used to measure epicardial fat volume. This review briefly introduces the basic physiological and pathophysiological considerations concerning epicardial fat. The main issue of this review is the presentation of non-invasive measurement techniques of epicardial fat using various imaging modalities and a literature overview of associations between epicardial fat and common cardiovascular diseases.


Assuntos
Tecido Adiposo/patologia , Adiposidade , Doenças Cardiovasculares/diagnóstico , Diagnóstico por Imagem/métodos , Pericárdio/patologia , Humanos
12.
Int J Cardiovasc Imaging ; 28(1): 89-97, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21153708

RESUMO

This study was performed to assess the role of additional myocardial perfusion imaging during high dose dobutamine/atropine stress magnetic resonance (DSMR-wall motion) for the evaluation of patients with intermediate (50-70%) coronary artery stenosis. Routine DSMR-wall motion was combined with perfusion imaging (DSMR-perfusion) in 174 consecutive patients with chest pain syndromes who were scheduled for a clinically indicated coronary angiography. When defining CAD as the presence of a ≥ 50% stenosis, the addition of perfusion imaging improved sensitivity (90 vs. 79%, P < 0.001) with a non-significant reduction in specificity (85 vs. 90%, P = 0.13) and an improvement in overall diagnostic accuracy (88 vs. 84%, P = 0.008). Adding perfusion imaging improved sensitivity in patients with intermediate stenosis (87 vs. 72%, P = 0.03), but not in patients with severe (≥70%) stenosis (93 vs. 84%, P = 0.06). In patients with severe stenosis specificity of DSMR-perfusion versus DSMR-wall motion decreased (61 vs 70%, P = 0.001) resulting in a lower overall accuracy (71 vs 74%, P = 0.03). Using a cutoff of ≥50% for the definition of CAD, sensitivity of DSMR-perfusion compared to DSMR-wall motion was significantly higher in patients with single vessel (88 vs. 77%, P = 0.03) and multi vessel disease (93 vs. 79%, P = 0.03), whereas no significant differences were found using a cutoff of ≥70% stenosis for the definition of CAD. The addition of perfusion imaging during DSMR-wall motion improved the sensitivity in patients with intermediate coronary artery stenosis. Overall diagnostic accuracy increased only when defining CAD as ≥50% stenosis. In patients with ≥70% stenosis DSMR-wall motion alone had higher accuracy due to more false-positive cases with DSMR-perfusion.


Assuntos
Doença da Artéria Coronariana/patologia , Dobutamina , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Análise de Variância , Dor no Peito/complicações , Meios de Contraste , Angiografia Coronária/métodos , Doença da Artéria Coronariana/complicações , Estenose Coronária/complicações , Estenose Coronária/patologia , Feminino , Gadolínio DTPA , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Int J Cardiol ; 158(3): 411-6, 2012 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-21345497

RESUMO

PURPOSE: To prospectively evaluate the feasibility and diagnostic accuracy of high spatial resolution myocardial perfusion imaging during high dose dobutamine/atropine stress magnetic resonance (DSMR) for the detection of coronary artery disease (CAD). METHODS AND RESULTS: DSMR-wall motion was combined with perfusion imaging (DSMR-perfusion) in 78 patients prior to clinically indicated invasive coronary angiography. For DSMR-perfusion an in-plane spatial resolution of 1.5 × 1.5mm(2) was attained by using 8 × k-space and time sensitivity encoding (k-t SENSE). Image quality and extent of artifacts during perfusion imaging were evaluated. Wall motion and perfusion data were interpreted sequentially. Significant CAD (stenosis ≥ 70%) was present in 52 patients and involved 86 coronary territories. One patient did not reach target heart rate despite maximum infusion of dobutamine/atropine. Two studies (3%) were non-diagnostic due k-t SENSE related artifacts resulting from insufficient breathhold capability. Overall image quality was good. Dark-rim artifacts were limited to the endocardial border at a mean width of 1.8mm. The addition of DSMR-perfusion to DSMR-wall motion data improved sensitivity for the detection of CAD (92% vs. 81%, P=0.03) and accurate determination of disease extent (85% vs. 66% of territories, P<0.001). There were no significant differences between DSMR-perfusion and DSRM-wall motion regarding overall specificity (83% vs. 87%, P=1) and accuracy (89% vs. 83%, P=0.13). CONCLUSION: High spatial resolution DSMR-perfusion imaging at maximum stress level was feasible, improved sensitivity over DSMR-wall motion for the detection of CAD and allowed an accurate determination of disease extent. Specificity of DSMR-perfusion with k-t SENSE improved compared to prior studies using lower spatial resolution.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Doença da Artéria Coronariana/patologia , Teste de Esforço/métodos , Imageamento por Ressonância Magnética/métodos , Isquemia Miocárdica/patologia , Idoso , Artefatos , Atropina/administração & dosagem , Cardiotônicos/administração & dosagem , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Dobutamina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/administração & dosagem , Isquemia Miocárdica/diagnóstico por imagem , Estudos Prospectivos , Sensibilidade e Especificidade
15.
Heart ; 96(8): 616-20, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19687013

RESUMO

BACKGROUND: Dobutamine stress magnetic resonance (DSMR) imaging represents an excellent imaging approach for the detection of coronary artery disease (CAD). However, most studies have predominantly reported the utility of DSMR in men. OBJECTIVE: To evaluate the diagnostic value of DSMR in men and women. METHODS AND RESULTS: High-dose dobutamine/atropine stress magnetic resonance imaging was performed and new or worsening wall motion abnormalities evaluated in 745 consecutive patients (204 women, 541 men). Invasive coronary angiography was performed within 30 days and served as the reference standard (> or =70% stenosis). DSMR was technically successful and had diagnostic image quality in all patients except one woman and three men (p=NS). In the absence of ischaemia, target heart rate was not reached in 9.3% of women and 8.5% of men (P=NS) despite maximum pharmacological infusion (1% and 2.2%, respectively, p=NS) or owing to limiting side effects (8.3% and 6.3%, respectively, p=NS). Diagnostic values (sensitivity/specificity/accuracy) for the detection of significant coronary stenoses were similar for men (86%/83%/85%) and women (85%/86%/85%). There was no gender-based difference in regional diagnostic accuracy of DSMR for all three coronary vascular territories in patients with single-vessel CAD (81% vs 81%, p=NS, respectively). CONCLUSION: The diagnostic capability of DSMR for the detection of haemodynamically relevant, obstructive CAD is independent of gender.


Assuntos
Cardiotônicos , Doença da Artéria Coronariana/diagnóstico , Dobutamina , Angiografia por Ressonância Magnética/métodos , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores Sexuais
16.
Eur J Radiol ; 61(2): 256-61, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17034975

RESUMO

OBJECTIVES: We evaluated the feasibility of highfield lung-MRI at 3.0T. A comparison with Computed Tomography (CT) and clinical data regarding the assessment of inflammatory activity in patients with diffuse lung disease was performed. MATERIAL AND METHODS: Prospective evaluation of 21 patients (15 males, 6 females, 43-80 y) with diffuse lung diseases who underwent clinical work-up inclusive laboratory tests, lung-function tests and transbronchial biopsy. After routine helical CT (additional 12 HRCT) a lung-MRI (3.0 Intera, Philips Medical Systems, Best, The Netherlands) using a T2-weighted, cardiac and respiratory triggered Fast-Spinecho-Sequence (TE/TR=80/1500-2500 ms, 22 transverse slices, 7/2mm slice-thickness/-gap) was performed. A pneumologist classified the cases into two groups: A=temporary acute interstitial disease or chronic interstitial lung disease with acute episode or superimposed infection/B=burned out interstitial lung disease without activity. Two blinded CT-radiologists graded the cases in active/inactive disease on the basis of nine morphological criteria each. A third radiologist rated the MRI-cases as active/inactive, depending on the signal-intensities of lung tissues. RESULTS: The pneumologist classified 14 patients into group A and 7 patients into group B. Using CT, 6 cases were classified as active, 15 cases as inactive disease. With MRI 12 cases were classified as active and 9 cases as inactive. In the complete group of 21 patients MRI decisions and CT decisions respectively were false positive/false negative/correct in 2/4/15 respectively 0/8/13 cases. Correct diagnoses were obtained in 72% (MRI) respectively 62% (CT). In the subgroup of 12 cases including HRCT, MRI respectively CT were false positive/false negative/correct in 2/1/9 respectively 0/5/7 cases. Correct diagnoses were obtained in 75% (MRI) respectively 58% (CT). CONCLUSION: Highfield MRI of the lung is feasible and performed slightly better compared to CT in the determination of activity in patients with interstitial lung diseases.


Assuntos
Inflamação/fisiopatologia , Doenças Pulmonares Intersticiais/fisiopatologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Inflamação/diagnóstico por imagem , Inflamação/patologia , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
17.
Clin Res Cardiol ; 95(1): 23-30, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16598442

RESUMO

OBJECTIVE: The aim of this study was to evaluate the impact of obstructive sleep apnea syndrome (OSAS) on B-type natriuretic peptide (BNP) and to determine the effect of nasal continuous positive airway pressure (nCPAP) treatment on BNP levels. BACKGROUND: Increased sympathetic activity, repetitive rises in blood pressure, and apnea-induced wall stress may contribute as a trigger to release BNP in OSAS. However, there is uncertainty about whether OSAS affects BNP and whether application of nasal continuous positive airway pressure (nCPAP) ventilation affects release of BNP. PATIENTS AND METHODS: A prospective study in 69 consecutive patients with suspected sleep disordered breathing referred to our sleep laboratory was conducted. OSAS was confirmed in 26 normotensive and 34 hypertensive patients and ruled out in nine normotensive patients (controls) by polysomnography (PSG). RESULTS: Baseline N-terminal fragment of BNP prohormone (NT-pro-BNP) did not differ significantly between OSAS patients (hypertensive: mean +/-SEM 60.8+/-9.9 pg/ml, normotensive: 43.2+/-6.8 pg/ml) and controls (36.5+/-8.5 pg/ml). Application of CPAP resulted in a significant decrease of NT-pro-BNP in hypertensive (60.8+/-9.9 pg/ml to 47.6+/-7.4 pg/ml, p=0.023) and normotensive OSAS (43.2+/-6.8 pg/ml to 29.6+/-5.3 pg/ml, p=0.0002). In contrast, controls showed no significant differences in NT-pro-BNP after a second PSG (36.5+/-8.5 pg/ml to 40.7+/-12.3 pg/ml, p=0.597). CONCLUSIONS: Normotensive and hypertensive OSAS was not associated with a significant elevation of NT-pro-BNP. Application of nCPAP decreased NT-pro-BNP levels significantly in normotensive and, in particular, hypertensive OSAS. These findings may provide further evidence of the potential for nCPAP to improve cardiovascular comorbidity and co-mortality in OSAS and sleep disordered breathing, in general.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Hipertensão/sangue , Hipertensão/prevenção & controle , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/terapia , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Apneia Obstrutiva do Sono/complicações , Resultado do Tratamento
18.
Basic Res Cardiol ; 100(5): 439-45, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15944808

RESUMO

BACKGROUND: Patients with obstructive sleep apnea (OSA) are at increased risk for cardiovascular disease. Increased sympathetic drive is considered as one of the underlying mechanisms. Both heart rate turbulence (HRT) and heart rate variability (HRV) are parameters to describe autonomic regulation. We investigated the influence of sleep-disordered breathing (SDB) on HRT and HRV in patients with OSA. METHODS: Sixty-five patients underwent overnight polysomnography for clinically suspected SDB and simultaneous Holter monitoring (11 p.m.-6 a.m.). Patients with diabetes mellitus, a history of cardiac disease, left ventricular dysfunction, periodic breathing pattern, and those on beta-blockers or theophylline were excluded. According to the apnea-hypopnea index (AHI), the patients were assigned to group A (AHI <20, n = 31) or group B (AHI > or =20, n = 34). HRV (time domain, frequency domain) and HRT (onset, slope) were then related to the severity of SDB. RESULTS: Nighttime turbulence slope (TS) correlated inversely with the AHI (r = -0.45, p = 0.01) and was significantly lower in group B (8.9 +/- 1.6 ms/R-R interval) compared with that in group A (19.8 +/- 4.0 ms/R-R interval, P = 0.01). This relationship remained stable after adjusting TS for the number of ventricular premature contractions. No significant differences in turbulence onset or parameters of nighttime HRV were observed. CONCLUSIONS: Alterations in nighttime HRT correlate with the severity of SDB, indicating abnormalities in cardiac autonomic activity in moderate-to-severe OSA even in the absence of overt cardiac disease. These changes may be associated with the subsequent development of cardiovascular disease.


Assuntos
Frequência Cardíaca , Apneia Obstrutiva do Sono/fisiopatologia , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Função Ventricular Esquerda
19.
Internist (Berl) ; 46(2): 195-201, 2005 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-15630596

RESUMO

A 73-year old healthy woman presented for pacemaker replacement. Chest X-ray showed an right upper lobe consolidation. CT-scan and bronchoscopy with bronchoalveolar lavage could not yield a specific diagnosis. Due to progression of the consolidation in a CT scan after 10 weeks another bronchoscopy with transbronchial biopsy was performed and yielded bronchiolo-alveolar carcinoma. The patient underwent resection of the right upper lobe and middle lobe with curative intent.


Assuntos
Adenocarcinoma Bronquioloalveolar/diagnóstico por imagem , Achados Incidentais , Neoplasias Pulmonares/diagnóstico por imagem , Marca-Passo Artificial , Síndrome do Nó Sinusal/terapia , Tomografia Computadorizada por Raios X , Adenocarcinoma Bronquioloalveolar/patologia , Adenocarcinoma Bronquioloalveolar/cirurgia , Idoso , Biópsia , Líquido da Lavagem Broncoalveolar , Broncoscopia , Diagnóstico Diferencial , Progressão da Doença , Feminino , Seguimentos , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo , Estadiamento de Neoplasias , Pneumonectomia
20.
Phys Rev D Part Fields ; 49(3): 1468-1478, 1994 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10017120
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