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Vila Nova de Gaia, Portugal

Schuster A.,Rayne Institute | Paul M.,Rayne Institute | Bettencourt N.,Rayne Institute | Bettencourt N.,Centro Hospitalar Of Gaia Espinho | And 10 more authors.
International Journal of Cardiology | Year: 2013

Background: Low dose dobutamine stress magnetic resonance imaging is valuable to assess viability in patients with ischemic cardiomyopathy. Analysis is usually qualitative with considerable operator dependency. The aim of the current study was to investigate the feasibility of cine images derived quantitative cardiac magnetic resonance (CMR) myocardial feature tracking (FT) strain parameters to assess viability in patients with ischemic cardiomyopathy. Methods: 15 consecutive patients with ischemic cardiomyopathy referred for viability assessment were studied at 3 T at rest and during low dose dobutamine stress (5 and 10 μg/kg/min of dobutamine). Subendocardial and subepicardial circumferential (Eccendo and Eccepi) and radial (Err) strains were assessed using steady state free precession (SSFP) cine images orientated in 3 short axis slices covering 16 myocardial segments. Results: Dysfunctional segments without scar (n = 75) improved in all three strain parameters: Eccendo (Rest: - 10.5 ± 6.9; 5 μg: - 12.1 ± 6.9; 10 μg: - 14.1 ± 9.2; p < 0.05), Eccepi (Rest: - 7 ± 4.8; 5 μg: - 8.2 ± 5.5; 10 μg: - 9.1 ± 5.9; p < 0.05) and Err (Rest: 11.7 ± 8.3; 5 μg: 16 ± 10.9; 10 μg: 16.5 ± 12.8; p < 0.05). There was no response to dobutamine in dysfunctional segments with scar transmurality above 75% (n = 6): Ecc endo (Rest: - 4.7 ± 3.0; 5 μg: - 2.9 ± 2.5; 10 μg: - 6.6 ± 3.3; p = ns), Eccepi (Rest: - 2.9 ± 2.9; 5 μg: - 5.4 ± 3.9; 10 μg: - 4.5 ± 4.2; p = ns) and Err (Rest:9.5 ± 5; 5 μg:5.4 ± 6.2; 10 μg:4.9 ± 3.3; p = ns). Circumferential strain (Eccendo, Eccepi) improved in all segments up to a transmurality of 75% (n = 60; p < 0.05). Err improved in segments < 50% transmurality (n = 45; p < 0.05) and remained unchanged above 50% transmurality (n = 21; p = ns). Conclusions: CMR-FT is a novel technique, which detects quantitative wall motion derived from SSFP cine imaging at rest and with low dose dobutamine stress. CMR-FT holds promise of quantitative assessment of viability in patients with ischemic cardiomyopathy. © 2011 Elsevier Ireland Ltd. Source


Sampaio F.,Centro Hospitalar Of Gaia Espinho | Pimenta J.,Centro Hospitalar Of Gaia Espinho | Pimenta J.,University of Porto
World Journal of Gastroenterology | Year: 2016

Cirrhotic cardiomyopathy has been defined as a chronic cardiac dysfunction in patients with cirrhosis characterized by impaired contractile responsiveness to stress and/or altered diastolic relaxation with electrophysiological abnormalities in the absence of other known cardiac disease. Non-invasive cardiovascular imaging modalities play a major role in unmasking systolic and diastolic dysfunction in patients with cirrhosis. Echocardiography has been the most commonly used modality for assessing myocardial function in these patients. Conventional echocardiographic indices rely on several assumptions that may limit their applicability in patients with a hyperdynamic circulation. Newer imaging modalities may contribute to a more accurate diagnosis of cardiovascular abnormalities in cirrhotic patients, thereby influencing clinical management. We aimed to review the different non-invasive imaging technologies currently used for assessing left ventricular systolic and diastolic function in cirrhosis, as well as to describe new imaging modalities with potential clinical applicability in the near future. © The Author(s) 2016. Source


Noronha-Matos J.B.,Abel Salazar Biomedical Sciences Institute | Costa M.A.,Abel Salazar Biomedical Sciences Institute | Magalhaes-Cardoso M.T.,Abel Salazar Biomedical Sciences Institute | Ferreirinha F.,Abel Salazar Biomedical Sciences Institute | And 7 more authors.
Journal of Cellular Physiology | Year: 2012

This study aimed at investigating the expression and function of uracil nucleotide-sensitive receptors (P2Y 2, P2Y 4, and P2Y 6) on osteogenic differentiation of human bone marrow stromal cells (BMSCs) in culture. Bone marrow specimens were obtained from postmenopausal female patients (68±5 years old, n=18) undergoing total hip arthroplasty. UTP and UDP (100μM) facilitated osteogenic differentiation of the cells measured as increases in alkaline phosphatase (ALP) activity, without affecting cell proliferation. Uracil nucleotides concentration-dependently increased [Ca 2+] i in BMSCs; their effects became less evident with time (7>21 days) of the cells in culture. Selective activation of P2Y 6 receptors with the stable UDP analog, PSB 0474, mimicked the effects of both UTP and UDP, whereas UTPγS was devoid of effect. Selective blockade of P2Y 6 receptors with MRS 2578 prevented [Ca 2+] i rises and osteogenic differentiation caused by UDP at all culture time points. BMSCs are immunoreactive against P2Y 2, P2Y 4, and P2Y 6 receptors. While the expression of P2Y 6 receptors remained fairly constant (7∼21 days), P2Y 2 and P2Y 4 became evident only in less proliferative and more differentiated cultures (7<21 days). The rate of extracellular UTP and UDP inactivation was higher in less proliferative and more differentiated cell populations. Immunoreactivity against NTPDase1, -2, and -3 rises as cells differentiate (7<21 days). Data show that uracil nucleotides are important regulators of osteogenic cells differentiation predominantly through the activation of UDP-sensitive P2Y 6 receptors coupled to increases in [Ca 2+] i. Endogenous actions of uracil nucleotides may be balanced through specific NTPDases determining whether osteoblast progenitors are driven into proliferation or differentiation. © 2011 Wiley Periodicals, Inc. Source


Duarte R.,Centro Hospitalar Of Gaia Espinho | Bettencourt N.,Centro Hospitalar Of Gaia Espinho | Costa J.C.,Joao Carlos Costa Diagnostico Por Imagem | Fernandez G.,Servico de Radiologia
Revista Portuguesa de Cardiologia | Year: 2010

Introduction: The aim of this study was to evaluate the radiation dose, image quality and acquisition time of coronary computed tomography angiography (CCTA) using a 128-slice dual source scanner with prospective ECG-triggered high-pitch spiral acquisition (Flash Spiral). Methods: A series of 20 consecutive patients in sinus rhythm, with no contraindications to administration of iodinated contrast media and beta-blockers and no history of coronary revascularization, underwent CCTA either to rule out coronary artery disease (CAD) or to evaluate known or suspected CAD. Image quality was evaluated using a four-point scale (1 excellent, 4 poor). Data on acquisition time and radiation dose were recorded. Results: Mean acquisition time was 292±21 milliseconds. The mean effective radiation dose was 0.99 mSv±0.34 mSv. All of the 266 coronary artery segments analyzed were of diagnostic image quality. Conclusion: CCTA using a 128-slice dual source scanner with prospective ECG-triggered high-pitch spiral acquisition provides single cardiac cycle acquisition with high image quality at mean effective radiation doses of approximately 1 mSv. Source


Bettencourt N.,Centro Hospitalar Of Gaia Espinho | Bettencourt N.,Kings College London | Bettencourt N.,University of Porto | Ferreira N.,Centro Hospitalar Of Gaia Espinho | And 14 more authors.
Circulation: Cardiovascular Imaging | Year: 2013

Background-Cardiovascular magnetic resonance (CMR) myocardial perfusion imaging (MPI) is a state-of-the-art noninvasive modality for detection of myocardial ischemia and coronary artery disease. Magnetic resonance coronary angiography (MRCA) allows visualization of the coronary tree, but its incremental value as part of a CMR protocol including MPI and late gadolinium enhancement (LGE) is not well established. We aimed to evaluate the additive diagnostic value of a 3-dimensional whole-heart MRCA integration into a 1.5T CMR-MPI/LGE protocol for the detection of functionally significant coronary artery disease. Methods and Results-Forty-three symptomatic patients (61±8.3 years; 65% men) with suspected coronary artery disease and intermediate/high-pretest probability underwent CMR (including CMR-MPI, MRCA, and LGE) and x-ray invasive coronary angiography (XA) with fractional flow reserve evaluation. Diagnostic performances of MRCA, CMR-MPI/LGE, and MRCA+CMR-MPI/LGE integration were determined having XA+fractional flow reserve as standard for coronary artery disease (≥90% stenosis/occlusion or fractional flow reserve≤0.80 in vessels>2 mm). MRCA inclusion into the CMR protocol was associated with a mean increase of 7.9±4.69 (0-17.7) minutes in total examination duration (14%). On patient-based analysis, MRCA had 96% sensitivity, 68% specificity, positive predictive value of 79%, and negative predictive value of 93%. CMR-MPI/LGE had 79% sensitivity, 95% specificity, positive predictive value of 95%, and negative predictive value of 78%. Integration of MRCA with CMR-MPI/LGE further improved CMR performance to 96% sensitivity, 89% specificity, positive predictive value of 92%, and negative predictive value of 94%, with a global accuracy of 93%. Conclusions-In this intermediate/high-pretest population, integration of noncontrast-enhanced whole-heart MRCA nonsignificantly improved per-patient diagnostic accuracy of a comprehensive 1.5-T stress-rest CMR-MPI/LGE protocol at a cost of longer scanning times. © 2013 American Heart Association, Inc. Source

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