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1.
Clin Imaging ; 105: 110025, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37989018

RESUMO

RATIONALE AND OBJECTIVES: There is universal interest in increasing sustainability in health care, including in imaging. We studied and characterized energy consumption in a representative imaging department in Denmark to identify and quantify the effect of specific optimizations. METHODS: Protocols and energy parameters for the three main scanner modalities along with supportive systems and workflows were monitored and scrutinized. Potential savings were measured and/or calculated. RESULTS: Only few optimizations were identified at the protocol level. However, examination of usage patterns and cooling systems revealed numerous potential optimizations which fell into three categories. 1) Optimizations requiring minimal changes in installations or workflows, for example, reduction of bed-position time, 2) optimizations requiring altered work flows such as strict adherence to timed shut-down procedures and 3) optimizations requiring retro-fitting equipment, typically at considerable monetary expense, for example fitting variable flow control on pumps. The single biggest identified optimization was raising the temperature of the circulating cooling water. CONCLUSION: This study highlights the complexity of increasing sustainability in health care, specifically in imaging. We identified multiple potential optimizations but also technical, monetary and organizational barriers preventing immediate implementation.


Assuntos
Atenção à Saúde , Diagnóstico por Imagem , Humanos
2.
Am J Gastroenterol ; 117(8): 1269-1278, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35916685

RESUMO

INTRODUCTION: Arterial vasodilation and hyperdynamic circulation are considered hallmarks of the pathophysiological mechanisms of decompensation in cirrhosis. However, detailed characterization of peripheral, splanchnic, renal, and cardiac hemodynamic have not previously been published in a spectrum from healthy stage to advanced decompensated liver disease with hepatorenal syndrome-acute kidney injury (HRS-AKI). METHODS: We included 87 patients with cirrhosis and 27 healthy controls in this prospective cohort study. The population comprised patients with compensated cirrhosis (n = 27) and decompensated cirrhosis (n = 60); patients with decompensated cirrhosis were further separated into subsets of responsive ascites (33), refractory ascites (n = 16), and HRS-AKI (n = 11). We measured portal pressure and assessed regional blood flow by magnetic resonance imaging. RESULTS: Patients with compensated cirrhosis experienced higher azygos venous flow and higher hepatic artery flow fraction of cardiac index than controls ( P < 0.01), but other flow parameters were not significantly different. Patients with decompensated cirrhosis experienced significantly higher cardiac index ( P < 0.01), higher superior mesenteric artery flow ( P = 0.01), and lower systemic vascular resistance ( P < 0.001) compared with patients with compensated cirrhosis. Patients with HRS-AKI had the highest cardiac output and lowest renal flow of all groups ( P < 0.01 and P = 0.02, respectively). Associations of single hemodynamic parameters were stronger with model for end-stage liver disease than with portal pressure. DISCUSSION: The regional cardiocirculatory changes seem closely linked to clinical symptoms with 3 distinguished hemodynamic stages from compensated to decompensated cirrhosis and, finally, to HRS-AKI. The attenuated renal perfusion despite high cardiac output in patients with HRS-AKI challenges the prevailing pathophysiological hypothesis of cardiac dysfunction as a causal factor in HRS-AKI. Finally, magnetic resonance imaging seems an accurate and reliable noninvasive method to assess hemodynamics and has potential as a diagnostic tool in patients with cirrhosis.


Assuntos
Injúria Renal Aguda , Doença Hepática Terminal , Síndrome Hepatorrenal , Injúria Renal Aguda/complicações , Injúria Renal Aguda/etiologia , Ascite , Doença Hepática Terminal/complicações , Síndrome Hepatorrenal/diagnóstico por imagem , Síndrome Hepatorrenal/etiologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/efeitos adversos , Estudos Prospectivos , Índice de Gravidade de Doença
3.
Clin Physiol Funct Imaging ; 37(6): 575-581, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26814057

RESUMO

PURPOSE: Right ventricular dysfunction (RVD) is an important prognostic factor of 30-day mortality in patients with acute pulmonary embolism (PE). The aim of our study was to evaluate whether non-electrocardiogram (ECG)-gated cardiovascular parameters attained during computed tomography pulmonary angiography (CTPA) could predict RVD in patients suspected of PE using ECG-gated cardiac CT angiography as reference. METHODS: Consecutive patients suspected of PE were referred to a ventilation/perfusion single-photon emission tomography (V/Q-SPECT) as first-line imaging procedure. Patients had a V/Q-SPECT/CT, a CTPA and an ECG-gated cardiac CT angiography performed the same day. RESULTS: A total of 71 patients were available for analysis. Seventeen patients (24%) had RVD. The non-ECG-gated dimensions of left and right ventricle and the major vessels were correlated with ECG-gated cardiac dimensions. The size of the pulmonary trunk could identify patients with RVD: AUC (0·67, 95% confidence intervals (CIs) 0·52-0·82) as seen in the ROC curve (P<0·05). With a cut-off value of the pulmonary trunk of 29 mm, the sensitivity and specificity were 70·6% and 55·5%, respectively. The positive predictive and negative predictive values for detection of RVD were 59·1% and 85·7%, respectively. CONCLUSION: In the present study, we demonstrated correlation between ECG-gated cardiac dimensions and non-ECG-gated cardiovascular parameters, however with only moderate diagnostic accuracies. We demonstrated that the dimension of the pulmonary trunk might be of value in detection of patients with RVD. We suggest further studies on the potential value of non-ECG-gated cardiac dimensions in patients suspected of PE.


Assuntos
Angiografia por Tomografia Computadorizada , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Função Ventricular Direita , Área Sob a Curva , Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Feminino , Humanos , Masculino , Imagem de Perfusão/métodos , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia , Embolia Pulmonar/complicações , Embolia Pulmonar/fisiopatologia , Curva ROC , Reprodutibilidade dos Testes , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/fisiopatologia
4.
Cardiovasc Diabetol ; 14: 59, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25990319

RESUMO

BACKGROUND: In patients with type 2 diabetes, cardiovascular disease (CVD) is the major cause of morbidity and mortality. We evaluated the combination of NT-proBNP and coronary artery calcium score (CAC) for prediction of combined fatal and non-fatal CVD and mortality in patients with type 2 diabetes and microalbuminuria (>30 mg/24-h), but without known coronary artery disease. Moreover, we assessed the predictive value of a predefined categorisation of patients into a high- and low-risk group at baseline. METHODS: Prospective study including 200 patients. All received intensive multifactorial treatment. Patients with baseline NT-proBNP > 45.2 ng/L and/or CAC ≥ 400 were stratified as high-risk patients (n = 133). Occurrence of fatal- and nonfatal CVD (n = 40) and mortality (n = 26), was traced after 6.1 years (median). RESULTS: High-risk patients had a higher risk of the composite CVD endpoint (adjusted hazard ratio [HR] 10.6 (95 % confidence interval [CI] 2.4-46.3); p = 0.002) and mortality (adjusted HR 5.3 (95 % CI 1.2-24.0); p = 0.032) compared to low-risk patients. In adjusted continuous analysis, both higher NT-proBNP and CAC were strong predictors of the composite CVD endpoint and mortality (p ≤ 0.0001). In fully adjusted models mutually including NT-proBNP and CAC, both risk factors remained associated with risk of CVD and mortality (p ≤ 0.022). There was no interaction between NT-proBNP and CAC for the examined endpoints (p ≥ 0.31). CONCLUSIONS: In patients with type 2 diabetes and microalbuminuria but without known coronary artery disease, NT-proBNP and CAC were strongly associated with fatal and nonfatal CVD, as well as with mortality. Their additive prognostic capability holds promise for identification of patients at high risk.


Assuntos
Doenças Cardiovasculares/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Calcificação Vascular/diagnóstico por imagem , Idoso , Albuminúria , Doenças Assintomáticas , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico por imagem , Estudos de Coortes , Diabetes Mellitus Tipo 2 , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos
5.
PLoS One ; 9(10): e109179, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25279659

RESUMO

BACKGROUND AND AIM: Cardiac dysfunction in patients with early cirrhosis is debated. We investigated potential cardiac dysfunction by assessing left ventricular systolic performance during a dobutamine stress test in patients with early cirrhosis. PATIENTS AND METHODS: Nineteen patients with Child A and B cirrhosis (9 with non-alcoholic cirrhosis) and 7 matched controls were included. We used cardiac magnetic resonance imaging to assess left ventricular volumes and cardiac output (CO) at rest and during maximal heart rate induced by increasing dosages of dobutamine and atropine. RESULTS: Patients with cirrhosis and controls had an equal stress response, the heart rate and ejection fraction increased similarly and maximal heart rate was reached in all. At rest CO was higher in Child B patients than controls. During maximal stress, Child B patients had higher CO (10.6±2.7 vs. 8.0±1.8 L/min), left ventricle end diastolic volume (90±25 vs. 67±16 mL), left ventricular end diastolic volume (10±4 vs. 6±2 mL) and stroke volume (80±23 vs. 61±15 mL) than Child A patients. The systemic vascular resistance was lower in Child B than Child A patients (670±279 vs. 911±274 dyne*s*cm(-5)). The left ventricle mass increased by 5.6 gram per model for end stage liver disease (MELD) point. MELD score correlated with the end diastolic and systolic volume, CO, and stroke volume at rest and at stress (all p<0.05). CONCLUSION: In patients with early cirrhosis the chronotropoic and inotropic response to pharmacological stress induced by dobutamine is normal. With progression of the disease, the mass of the heart increases along with increase in cardiac volumes.


Assuntos
Coração/fisiopatologia , Cirrose Hepática/fisiopatologia , Adulto , Idoso , Fator Natriurético Atrial/metabolismo , Ecocardiografia sob Estresse , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Scand J Gastroenterol ; 49(3): 362-72, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24329122

RESUMO

OBJECTIVE. Presence of cardiac dysfunction in patients with advanced cirrhosis is widely accepted, but data in early stages of cirrhosis are limited. Systolic and diastolic functions, dynamics of QT-interval, and pro-atrial natriuretic peptide (pro-ANP) are investigated in patients with early stage cirrhosis during maximal ß-adrenergic drive. MATERIAL AND METHODS. Nineteen patients with Child A (n = 12) and Child B cirrhosis (n = 7) and seven matched controls were studied during cardiac stress induced by increasing dosages of dobutamine and atropine. RESULTS. Pharmacological responsiveness was similar in cirrhosis and controls and the heart rate (HR) increased by 66 ± 15 versus 67 ± 8 min(-1). HR-blood pressure product increased equally by 115% in both cirrhotic patients and controls. However, time to resume HR of 100 beats/min was significantly longer in cirrhosis, p < 0.01. The QTc interval increased after dobutamine infusion in cirrhosis (0.41 ± 0.02 vs. 0.43 ± 0.02 s, p = 0.001) but similar electrophysiological changes were seen in controls. Cardiac volumes increased with the severity of disease. The increased cardiac output was primarily attributed to increased stroke volume. The ejection fraction was similar in patients and controls. Peak filling rate was longer in cirrhosis compared to controls (1.8 ± 0.4 and 1.4 ± 0.2 end-diastolic volume/s, p < 0.01). Pro-ANP was higher in cirrhosis and increased during stress by 13% compared to 0% in controls, p < 0.01. CONCLUSIONS. These findings indicate that patients with early stage cirrhosis exhibit early diastolic and autonomic dysfunction as well as elevated pro-ANP. However, the cardiac chronotropic and inotropic responses to dobutamine stress were normal. The dynamics of ventricular repolarization appears normal in patients with early stage cirrhosis.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca/fisiologia , Coração/fisiopatologia , Cirrose Hepática/fisiopatologia , Adolescente , Adulto , Idoso , Fator Natriurético Atrial/sangue , Atropina , Biomarcadores/sangue , Pressão Sanguínea , Débito Cardíaco/fisiologia , Estudos de Casos e Controles , Progressão da Doença , Dobutamina , Eletrocardiografia , Feminino , Humanos , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Parassimpatolíticos , Índice de Gravidade de Doença , Estresse Fisiológico/fisiologia , Simpatomiméticos , Adulto Jovem
7.
Pituitary ; 14(1): 1-10, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20730514

RESUMO

Assessed by conventional echocardiography the influence of growth hormone deficiency (GHD) and effects of replacement therapy on left ventricle (LV) function and mass (LVM) have shown inconsistent results. We aimed to evaluate cardiac function before and during replacement therapy employing the gold standard method cardiac magnetic resonance imaging (CMRI) and measurements of circulating levels of B-type natriuretic peptides. Sixteen patients (8 males and 8 females, mean age 49 years (range 18-75)) with severe GHD and 16 matched control subjects were included. CMRI was performed at baseline and after 1 year of GH replacement therapy. IGF-I, B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) were measured after 0, 1, 2, 3, 6 and 12 months of treatment. IGF-I Z-score increased from (median (IQR)) -2.3 (-3.8 to -1.4) to 0.5 (-0.3 to 1.7). LVM index (LVMI), ejection fraction (range 63-80%), cardiac output index and levels of BNP and NT-proBNP were similar at baseline in patients compared to controls (P-values from 0.09 to 0.37). The patients had significantly smaller LV end-diastolic volume index (P = 0.032) and end-systolic volume index (P = 0.038). No significant change in LV systolic function or LVM occurred during 1 year of GH treatment. BNP levels were unchanged (P = 0.88), whereas NT-proBNP tended to decrease (P = 0.052). Assessed by the highly sensitive and precise CMRI method, untreated GHD was not associated with impaired systolic function or reduced LVMI and 1 year of GH replacement using physiological doses did not influence cardiac mass or function.


Assuntos
Nanismo Hipofisário/tratamento farmacológico , Nanismo Hipofisário/patologia , Terapia de Reposição Hormonal/métodos , Hormônio do Crescimento Humano/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Função Ventricular Esquerda/efeitos dos fármacos , Adulto Jovem
8.
Nucl Med Commun ; 31(10): 874-80, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20700067

RESUMO

OBJECTIVES: The mechanisms underlying the increased cardiovascular risk in patients with HIV on antiretroviral therapy (ART) are not known. Our aim was to study the endothelial function of the coronary arteries by cardiac perfusion positron emission tomography (PET) in patients with HIV initiating ART. In addition, flow-mediated dilation (FMD) of the brachial artery was measured. METHODS: Patients with HIV scheduled to initiate ART (n=12) were included. NH3 perfusion PET and FMD scans were performed both before and 5 weeks (24-67 days) after initiation of ART. Data were compared with paired t-tests and a P value of less than 0.05 was considered significant. RESULTS: No changes were found in the pulse-pressure-corrected myocardial rest perfusion (1.22+/-0.07-1.09+/-0.05 ml/min/g tissue, NS) or cold pressor reserve (1.18+/-0.08-1.27+/-0.05, NS). However, the maximal myocardial perfusion decreased 31% from 2.50+/-0.25 to 1.73+/-0.15 ml/min/g tissue (P=0.009) and the myocardial perfusion reserve decreased 20% from 3.11+/-0.32 to 2.48+/-0.25 (P=0.042). FMD decreased from 8.68+/-1.70 to 4.58+/-0.93% (P=0.027). No change was observed in nitroglycerin-mediated dilation (12.8+/-1.0-14.4+/-1.4%, NS). CONCLUSION: In patients with HIV initiating ART, signs of development of endothelial dysfunction assessed by coronary perfusion PET and FMD were found early after starting medication.


Assuntos
Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Artéria Braquial/cirurgia , Vasos Coronários/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Sistema Vasomotor/efeitos dos fármacos , Adulto , Idoso , Amônia , Artéria Braquial/efeitos dos fármacos , Vasos Coronários/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Infecções por HIV/fisiopatologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio , Fatores de Tempo , Sistema Vasomotor/diagnóstico por imagem , Sistema Vasomotor/fisiopatologia , Adulto Jovem
9.
Pituitary ; 13(4): 329-36, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20697818

RESUMO

Long-term treatment of acromegaly prevents aggravation and reverses associated heart disease. A previous study has shown a temporary increase in serum levels of the N-terminal fraction of pro B-type natriuretic peptide (NT-proBNP) suggesting an initial decline in cardiac function when treatment of acromegaly is initiated. This was a three months prospective study investigating short-term cardiac effects of treatment in acromegalic patients. Cardiac function was evaluated by the gold standard method cardiac magnetic resonance imaging (CMRI) and circulating levels of B-type natriuretic peptides (BNP and NT-proBNP). CMRI was performed at baseline and after 3 months of treatment. Levels of IGF-I, BNP and NT-proBNP were measured after 0, 1, 2 and 3 months. Eight patients (5 males and 3 females, mean age 53 ± 12 years (range 30-70)) and 8 matched healthy control subjects were included. Median IGF-I Z-score decreased from 4.5 (range 2.5-6.4) to 2.3 (-0.1 to 3.3). At baseline the patients had increased left ventricle mass index (LVMI) compared to control subjects (ΔLVMI 35 g/m(2) (95% CI 8-63 g/m(2), P = 0.016). After 3 months of treatment there was an increase in end-diastolic volume index EDVI (ΔEDVI 9 mL/m(2) (95% CI 3-14), P = 0.007) and an increase in levels of BNP (median (ranges) 7 (0.58-286) vs. 20 (1-489) pg/mL, P = 0.033) and of NT-proBNP (63 (20-1004) vs. 80 (20-3391) pg/mL, P = 0.027). Assessed by the highly sensitive and precise CMRI method, 3 months treatment of acromegaly resulted in an increase in EDVI, and increased levels of BNP and NT-proBNP suggesting an initial decrease in cardiac function.


Assuntos
Acromegalia/sangue , Acromegalia/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Coração/efeitos dos fármacos , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/análogos & derivados , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Octreotida/efeitos adversos , Octreotida/uso terapêutico , Estudos Prospectivos , Somatostatina/efeitos adversos , Somatostatina/uso terapêutico
10.
Ugeskr Laeger ; 172(1): 41-3, 2010 Jan 04.
Artigo em Dinamarquês | MEDLINE | ID: mdl-20373564

RESUMO

The aim of our study was to perform a prospective study that compared the diagnostic ability of V/Q single photon emission computer tomography (V/Q-SPECT), V/Q-SPECT combined with low-dose computed tomography (CT) and pulmonary multidetector computed tomography(MDCT)-angiography in patients suspected of having pulmonary embolism (PE) using a dedicated combined SPECT/MDCT-scanner. V/Q-SPECT in combination with low-dose CT had a sensitivity of 97% and a specificity of 100%. MDCT angiography had a sensitivity of 68% and a specificity of 100%. We conclude that V/Q-SPECT in combination with low-dose CT without contrast has an excellent diagnostic performance and should be considered the first-line imaging technique in the work-up of PE in most cases.


Assuntos
Embolia Pulmonar/diagnóstico , Humanos , Pulmão/diagnóstico por imagem , Imagem de Perfusão , Valor Preditivo dos Testes , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Ventilação Pulmonar , Doses de Radiação , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
11.
Nucl Med Commun ; 31(1): 82-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19918207

RESUMO

PURPOSE: Planar ventilation/perfusion (V/Q) scintigraphy is currently the standard method for the diagnosis of pulmonary embolism (PE) in most nuclear medicine centers. However, recent studies have shown a superior sensitivity and specificity when applying V/Q single photon emission computed tomography (SPECT) in diagnosing PE. This study evaluated the diagnostic performance of three-dimensional V/Q SPECT in comparison with planar V/Q scintigraphy. MATERIALS AND METHODS: Consecutive patients suspected of acute PE from June 2006 to February 2008 were referred to the Department of Nuclear Medicine at Frederiksberg Hospital, Denmark to a V/Q SPECT, as the first-line imaging procedure. Patients with positive D-dimer (>0.5 mg/l) or after clinical assessment with a Wells score of more than 2 were included and had a V/Q SPECT, low-dose CT, planar V/Q scintigraphy, and pulmonary multidetector computer tomography angiography performed the same day. Ventilation studies were performed using Kr. Patient follow-up was at least 6 months. RESULTS: A total of 36 patient studies were available for analysis, of which 11 (31%) had PE. V/Q SPECT had a sensitivity of 100% and a specificity of 87%. Planar V/Q scintigraphy had a sensitivity of 64% and a specificity of 72%. CONCLUSION: We conclude that V/Q SPECT has a superior diagnostic performance compared with planar V/Q scintigraphy and should be preferred when diagnosing PE.


Assuntos
Pulmão/diagnóstico por imagem , Imagem de Perfusão , Embolia Pulmonar/diagnóstico por imagem , Ventilação Pulmonar , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Angiografia , Ecocardiografia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Extremidade Inferior/irrigação sanguínea , Pulmão/fisiopatologia , Masculino , Embolia Pulmonar/fisiopatologia , Doses de Radiação , Veias/diagnóstico por imagem
12.
J Nucl Med ; 50(12): 1987-92, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19910421

RESUMO

UNLABELLED: The diagnosis of pulmonary embolism (PE) is usually established by a combination of clinical assessment, D-dimer testing, and imaging with either pulmonary ventilation-perfusion (V/Q) scintigraphy or pulmonary multidetector CT (MDCT) angiography. Both V/Q SPECT and MDCT angiography seem to have high diagnostic accuracy. However, only limited data directly comparing these 2 modalities are available. Hybrid gamma-camera/MDCT systems have been introduced and allow simultaneous 3-dimensional lung V/Q SPECT and MDCT angiography, suitable for diagnosing PE. The aim of our study was to compare, in a prospective design, the diagnostic ability of V/Q SPECT, V/Q SPECT combined with low-dose CT, and pulmonary MDCT angiography obtained simultaneously using a combined SPECT/MDCT scanner in patients suspected of having PE. METHODS: Consecutive patients from June 2006 to February 2008 suspected of having acute PE were referred to the Department of Nuclear Medicine at Rigshospitalet or Frederiksberg Hospital, Denmark, for V/Q SPECT as a first-line imaging procedure. The number of eligible patients was 196. Patients with positive D-dimer results (>0.5 mmol/mL) or a clinical assessment with a Wells score greater than 2 were included and underwent V/Q SPECT, low-dose CT, and pulmonary MDCT angiography in a single session. Patient follow-up was 6 mo. RESULTS: A total of 81 simultaneous studies were available for analysis, of which 38% were from patients with PE. V/Q SPECT had a sensitivity of 97% and a specificity of 88%. When low-dose CT was added, the sensitivity was still 97% and the specificity increased to 100%. Perfusion SPECT with low-dose CT had a sensitivity of 93% and a specificity of 51%. MDCT angiography alone had a sensitivity of 68% and a specificity of 100%. CONCLUSION: We conclude that V/Q SPECT in combination with low-dose CT without contrast enhancement has an excellent diagnostic performance and should therefore probably be considered first-line imaging in the work-up of PE in most cases.


Assuntos
Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Doses de Radiação , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão , Embolia Pulmonar/fisiopatologia , Ventilação Pulmonar , Sensibilidade e Especificidade , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
13.
Ugeskr Laeger ; 170(45): 3637-9, 2008 Nov 03.
Artigo em Dinamarquês | MEDLINE | ID: mdl-18988366

RESUMO

Mortality rates due to coronary arterial disease (CAD) have declined as result of improved prevention, diagnosis and management, but CAD remains the leading cause of death. Myocardial perfusion scintigraphy (MPS) provides a cost-effective tool for early detection of CAD in symptomatic individuals and can stratify patients according to risk of cardiac events. MPS also provides valuable information to assist clinical decision-making. A large body of evidence supports the current applications of MPS, which has become integral to several guidelines for clinical practice.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/mortalidade , Doença da Artéria Coronariana/mortalidade , Análise Custo-Benefício , Medicina Baseada em Evidências , Humanos , Tomografia por Emissão de Pósitrons , Prognóstico , Tomografia Computadorizada de Emissão de Fóton Único
14.
Eur J Nucl Med Mol Imaging ; 35(11): 2049-58, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18661131

RESUMO

BACKGROUND: The mechanisms underlying increased cardiovascular risk in HIV patients in antiretroviral therapy (ART) are not known. Our aim was to study the endothelial function of the coronary arteries by cardiac perfusion positron emission tomography (PET), in HIV patients with normal or high cholesterol levels. Flow mediated dilation (FMD) of the brachial artery and circulating endothelial markers were also assessed. METHODS AND RESULTS: HIV patients in ART with total cholesterol or= 6.5 mmol/L (254 mg/dL; n = 12) and healthy controls (n = 14) were included. (13)NH(3) perfusion PET, FMD, and measurement of plasma levels of E-Selectin, ICAM-1, VCAM-1, tPAI-1, and hs-CRP were performed. Baseline myocardial perfusion and the coronary flow reserve measured by PET (3.2 +/- 0.3, 3.2 +/- 0.3 and 3.0 +/- 0.3; ns) was similar in HIV patients with normal or high total cholesterol and controls. FMD did not differ between the groups and was 4.6 +/- 1.1%, 5.1 +/- 1.2%, and 4.6 +/- 0.8%, respectively. Increased levels of plasma E-Selectin, ICAM-1, tPAI-1, and hs-CRP were found in HIV patients when compared to controls (p < 0.05). E-Selectin and ICAM-1 levels were higher in HIV patients receiving protease inhibitors (PI) compared to those not receiving PI (p < 0.05). None of the measured endothelial biomarkers differed between the normal and high cholesterol HIV groups. CONCLUSIONS: In ART-treated HIV patients with a low overall cardiovascular risk, no sign of endothelial dysfunction was found not even in hypercholesterolemic patients. Also, the increased level of plasma endothelial markers found in HIV patients was not related to hypercholesterolemia.


Assuntos
Endotélio/diagnóstico por imagem , Endotélio/fisiopatologia , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/fisiopatologia , Hipercolesterolemia/induzido quimicamente , Miocárdio/citologia , Adolescente , Adulto , Antivirais/efeitos adversos , Biomarcadores/sangue , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Estudos de Casos e Controles , Colesterol/metabolismo , Circulação Coronária , Endotélio/irrigação sanguínea , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Humanos , Hipercolesterolemia/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Risco , Ultrassonografia , Sistema Vasomotor/fisiopatologia
15.
Clin Physiol Funct Imaging ; 27(6): 363-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17944658

RESUMO

BACKGROUND: The presence of autonomic dysfunction in HIV patients is largely unknown. Early studies found autonomic dysfunction in patients with AIDS. Introduction of highly active antiretroviral combination therapy (ART) has dramatically changed the course of the disease and improved prognosis and decreased morbidity. At present it is not known whether introduction of ART also has decreased autonomic dysfunction. AIM: To evaluate whether autonomic dysfunction is present in an ART-treated HIV population. METHODS: HIV patients receiving ART for at least 3 years (n = 16) and an age-matched control group of healthy volunteers (n = 12) were included. All were non-smokers, non-diabetic and had never received medication for dyslipidaemia or hypertension. Following a 10 min resting period a 5 min ECG recording was performed. Heart rate variability (HRV) analysis was performed in accordance with current guidelines and data reported as median (interquartile range). RESULTS: The resting heart rate was higher in HIV patients compared with controls [69 (62-74) versus 57 (52-60); P<0.001]. Total HRV measured as standard deviation of normal-to-normal (SONN) was lower in the HIV group compared with the controls [36 (25-55) versus 74 (57-84) ms; P<0.01] as was parasympathetic activity measured as square root of the mean squared difference of successive normal-to-normal intervals (RMSSD) [22 (9-30) versus 35 (24-62) ms; P<0.05]. Low frequency power was lower in the HIV group compared with the control group [294 (161-602) versus 946 (711-1668) ms(2); P<0.01]. High frequency power as well as systolic and diastolic blood pressure did not differ between the groups. CONCLUSIONS: The HIV patients in ART have increased resting heart rate and decreased short-term heart rate variability indicating parasympathetic dysfunction.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Doenças do Sistema Nervoso Autônomo/complicações , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Infecções por HIV/prevenção & controle , Infecções por HIV/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Clin Physiol Funct Imaging ; 27(3): 173-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17445068

RESUMO

INTRODUCTION: Increased cardiovascular risk in HIV patients in antiretroviral therapy (ART) may be due to HIV infection, direct effect of ART or dyslipidaemia induced by ART. Our aim was to study the relative importance of HIV, ART and dyslipidaemia on atherosclerosis, assessed by the comparison of carotid artery intima-media thickness (IMT) in non-smoking HIV patients with high or low serum cholesterol levels as well as in healthy volunteers. METHODS: HIV patients in ART with normal cholesterol (or=6 x 5 mmol l(-1); n=12) as well as healthy controls (n=14) were included. All were non-smokers and had never received medication for dyslipidaemia or hypertension. IMT was measured by ultrasonography. RESULTS: In HIV patients with normal cholesterol (or=6 x 5 mmol l(-1)) and in controls (5 x 1 +/- 0 x 9 mmol l(-1)) IMT were 683 +/- 119, 656 +/- 99 and 657 +/- 99 microm, respectively. Thus no difference in IMT was found between the three groups. IMT values did not differ between patients receiving and not receiving protease inhibitors (658 +/- 117 microm versus 687 +/- 97 microm, P>0 x 05). In HIV patients IMT correlated inversely with HDL cholesterol levels (r=-0 x 50; P=0 x 01), whereas no correlation was found with total cholesterol or LDL cholesterol. CONCLUSIONS: In non-smoking HIV patients receiving ART no sign of accelerated atherosclerosis was found as assessed by IMT even not in hypercholesterolaemic HIV patients. IMT correlated with HDL cholesterol but not with LDL cholesterol. Based on these observations, one could speculate whether selective lowering of LDL cholesterol will be successful in reducing cardiovascular risk in non-smoking HIV patients.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Doenças das Artérias Carótidas/etiologia , Infecções por HIV/tratamento farmacológico , Túnica Íntima/patologia , Túnica Média/patologia , Adolescente , Adulto , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/patologia , Feminino , Infecções por HIV/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Ultrassonografia
17.
Angiology ; 57(3): 341-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16703194

RESUMO

Impaired right ventricular (RV) function has been reported to occur in patients with HIV when studied by echocardiography. However, for accurate evaluation of RV function and morphology, first-pass radionuclide ventriculography (RNV) and cine magnetic resonance imaging (cine-MRI) are methods of choice. Studies of RV involvement in patients with HIV are of interest since pulmonary hypertension is a known serious complication of HIV recognized with increasing frequency. The aim of the present study was to characterize cardiac function and geometry in patients with HIV and reduced right ventricular ejection fraction (RVEF). To do so, we screened patients with RNV and performed an additional cine-MRI in those with reduced RVEF determined by RNV. Ninety patients with HIV were included. To evaluate the MRI measures exactly we included 18 age- and gender-matched healthy volunteers to establish reference values. RNV showed in 13 of the 90 patients a reduced RVEF with a standard cutoff value for RVEF of 0.50. Six of these agreed to have an additional MRI investigation performed. These 6 patients with HIV had an RVEF measured by RNV between 0.41-0.49. Measured by MRI the range of RVEF was 0.47-0.55 with 3 below the lower 95% reference limit according to the control group (lower reference limit: 0.49). None of the 6 patients with HIV had dilated right ventricle and only 1 had a marginally increased right ventricular mass index of 43 g/m(2) (reference: <41 g/m(2)). With use of MRI, a few patients with HIV may have a marginally reduced RVEF but normal RV dimensions and mass. Thus, RV dysfunction does not seem to constitute a major clinical problem in this antivirally treated HIV population.


Assuntos
Infecções por HIV/patologia , Imagem Cinética por Ressonância Magnética , Disfunção Ventricular Direita/diagnóstico , Ventriculografia de Primeira Passagem , Adulto , Terapia Antirretroviral de Alta Atividade , Volume Cardíaco , Feminino , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Ventrículos do Coração/patologia , Humanos , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Disfunção Ventricular Direita/patologia
18.
Eur J Echocardiogr ; 7(6): 430-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16338173

RESUMO

AIMS: Radionuclide techniques, and recently MRI, have been used for clinical evaluation of right ventricular (RV) volumes function (RVEF) and volumes; but with the introduction of 3D echocardiography, new echocardiographic possibilities for RV evaluation independent of geometrical assumptions have emerged. This study compared classic and new echocardiographic and radionuclide estimates, including gated blood pool single-photon emission computed tomography (SPECT) of RV size and function to RV volumes, and ejection fraction (RVEF) measured by magnetic resonance imaging (MRI). METHODS AND RESULTS: Thirty-four subjects with (a) prior inferior ST-elevation myocardial infarction (n=17), (b) a history of pulmonary embolism and persistent dyspnea (n=7) or (c) normal subjects (n=10) had 2D and 3D echocardiography, SPECT and MRI within 24h. End-diastolic volume and peak tricuspid regurgitation velocity were increased in patients with a history of pulmonary embolism compared to healthy subjects, 130+/-26 ml vs. 94+/-26 ml, P<0.05, and 3.3+/-1.1m/s vs. 2.3+/-0.3m/s, P<0.05, respectively, whereas no differences in RVEF were seen in the three groups. Echocardiographic as well as SPECT estimates of RV volume showed significant correlation to RV volumes by MRI. Tricuspid annular plane systolic excursion (TAPSE) had the better correlation to RVEF by MRI, r=0.48, P<0.01; whereas 3D echocardiography had a correlation of 0.42, P<0.05. Compared to MRI, 3D echocardiography underestimated RVEF by 5.9%, 95% limits of agreement 1.6-10.2%. CONCLUSION: 3D echocardiographic estimates of RV size and RVEF show only moderate correlation to MRI measures of these parameters, and simple 2D echocardiographic estimates of RV size and function show similar correlations. For routine clinical purposes the simple TAPSE may be preferred over 3D and SPECT techniques for RVEF estimation.


Assuntos
Volume Cardíaco/fisiologia , Ecocardiografia Tridimensional , Ecocardiografia , Imageamento por Ressonância Magnética , Função Ventricular Direita/fisiologia , Idoso , Análise de Variância , Feminino , Imagem do Acúmulo Cardíaco de Comporta/métodos , Coração/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único , Ventriculografia de Primeira Passagem
19.
Clin Physiol Funct Imaging ; 25(6): 344-9, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16268986

RESUMO

BACKGROUND: Right ventricular (RV) function is of interest in an array of cardiopulmonary diseases. First-pass radionuclide ventriculography (FP), gated blood-pool single photon emission tomography (GBPS) and cardiac magnetic resonance imaging (MRI) are three currently used non-invasive methods for evaluation of right-sided cardiac function. The aim of our study was to compare the agreement between these methods when measuring right-sided cardiac function. METHODS: Twenty-four healthy volunteers were included. Mean age was 44 years (range: 25-60) and 29% were females. All participants had FP, GBPS and breath-hold cine MRI performed according to standard protocols. RESULTS: Normal ranges for RV ejection fraction (RVEF) defined as mean +/- 2SD were 0.49-0.72, 0.44-0.66 and 0.40-0.69 when measured by MRI, FP and GBPS respectively. Bland-Altman analysis showed a mean difference (bias) between MRI and FP of 0.05 (95% CI: 0.03-0.08) and of 0.06 (95% CI: 0.02-0.10) between MRI and GBPS. No systematic bias was found between FP and GBPS. Normal values for RV end-diastolic volume index (RVEDVI) were 37-95 and 29-91 ml m(-2) when measured by MRI and GBPS respectively. The mean difference between RVEDVI was 6 ml m(-2) (95% CI: 0-11). CONCLUSIONS: (i) Normal values of RVEF differ between MRI, FP and GBPS with wide limits of agreement, accordingly it is difficult to evaluate changes over time if measured by different methods, (ii) RV volumes are in the same range when measured by MRI or GBPS but with wide limits of agreement, and (iii) if MRI is considered gold standard then FP is more accurate than GBPS for RVEF measurements.


Assuntos
Imagem do Acúmulo Cardíaco de Comporta/métodos , Imagem Cinética por Ressonância Magnética/métodos , Volume Sistólico/fisiologia , Função Ventricular Direita/fisiologia , Ventriculografia de Primeira Passagem/métodos , Adulto , Feminino , Ventrículos do Coração/anatomia & histologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Função Ventricular
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