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1.
Eur Radiol ; 25(8): 2310-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25913571

RESUMO

OBJECTIVES: To prospectively evaluate image quality (IQ) and radiation dose of dual-source cardiac computed tomography (CCTA) using different imaging protocols. METHODS: CCTA was performed in 150 patients using the retrospective ECG-gated spiral technique (rECG) the prospective ECG-gated technique (pECG), or the prospective ECG-gated technique with systolic imaging and automated tube voltage selection (pECGsys). IQ was rated using a 16-segment coronary artery model. Techniques were compared for overall IQ, IQ of the large and the small coronary artery segments. Effective dose was used for comparison of radiation dose. RESULTS: Overall IQ and IQ of the large segments showed no differences between the groups. IQ analysis of the small segments showed lowered IQ in pECGsys compared to rECG (p = 0.02), but not to pECG (p = 0.6). Effective dose did not differ significantly between rECG and pECG (p = 0.13), but was significantly lower for pECGsys (p < 0.001 vs. rECG and pECG). CONCLUSION: Radiation dose of dual-source CCTA in heart transplant recipients is significantly reduced by using prospective systolic scanning and automated tube voltage selection, while overall IQ and IQ of the large coronary segments are maintained. IQ appears to be lower compared to retrospective techniques with regard to small coronary segments. KEY POINTS: • Cardiac computed tomography angiography is useful for cardiac allograft vasculopathy assessment. • Despite elevated heart rate, dose reduction in cardiac computed tomography is possible. • Prospective systolic gating and automated tube voltage selection enable 50 % dose reduction.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Vasos Coronários/diagnóstico por imagem , Transplante de Coração , Complicações Pós-Operatórias/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia/métodos , Feminino , Seguimentos , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sístole , Tomografia Computadorizada Espiral/métodos , Adulto Jovem
2.
Basic Res Cardiol ; 107(5): 292, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22899170

RESUMO

Although epicardial blood flow can be restored by an early intervention in most cases, a lack of adequate reperfusion at the microvascular level is often a limiting prognostic factor of acute myocardial infarction (AMI). Our group has recently found that paracrine factors secreted from apoptotic peripheral blood mononuclear cells (APOSEC) attenuate the extent of myocardial injury. The aim of this study was to determine the influence of APOSEC on microvascular obstruction (MVO) in a porcine AMI model. A single dose of APOSEC was intravenously injected in a closed chest reperfused infarction model. MVO was determined by magnetic resonance imaging and cardiac catheterization. Role of platelet function and vasodilation were monitored by means of ELISA, flow cytometry, aggregometry, western blot and myographic experiments in vitro and in vivo. Treatment of AMI with APOSEC resulted in a significant reduction of MVO. Platelet activation markers were reduced in plasma samples obtained during AMI, suggesting an anti-aggregatory capacity of APOSEC. This finding was confirmed by in vitro tests showing that activation and aggregation of both porcine and human platelets were significantly impaired by co-incubation with APOSEC, paralleled by vasodilator-stimulated phosphoprotein (VASP)-mediated inhibition of platelets. In addition, APOSEC evidenced a significant vasodilatory capacity on coronary arteries via p-eNOS and iNOS activation. Our data give first evidence that APOSEC reduces the extent of MVO during AMI, and suggest that modulation of platelet activation and vasodilation in the initial phase after myocardial infarction contributes to the improved long-term outcome in APOSEC treated animals.


Assuntos
Leucócitos Mononucleares/fisiologia , Infarto do Miocárdio/terapia , Agregação Plaquetária , Vasodilatação , Animais , Moléculas de Adesão Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Técnicas In Vitro , Leucócitos Mononucleares/metabolismo , Proteínas dos Microfilamentos/fisiologia , Fosfoproteínas/fisiologia , Ativação Plaquetária , Suínos
3.
Nuklearmedizin ; 50(1): 9-14, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21165540

RESUMO

AIM: We compared and delineated possible differences of model-based analysis of ECG-gated SPECT using (99m)Tc-sestamibi (Tc-SPECT) with ECG-gated ¹8F-fluorodeoxyglucose-PET (FDG-PET) for determination of end-diastolic (EDV) and end-systolic (ESV) cardiac volumes, left ventricular ejection fraction (LVEF), and myocardial mass (LVMM). PATIENTS, METHODS: 24 patients (21 men; age: 54±12years) with coronary artery disease underwent Tc-SPECT and FDG-PET imaging for evaluation of myocardial perfusion and viability. By using model-based analysis EDV, ESV, LVEF and LVMM were calculated from short axis images of both Tc-SPECT and FDG-PET. RESULTS: Left ventricular volumes by Tc-SPECT and FDG-PET were 176±60 ml and 181±59 ml for EDV, and 97±44 ml and 103±45 ml for ESV respectively, LVEF was 47±8% by Tc-SPECT and 45±9% by FDG-PET. The LVMM was 214±40 g (Tc-SPECT) and 202±43 g (FDG-PET) (all p = NS, paired t-test). A significant correlation was observed between Tc-SPECT and FDG-PET imaging for calculation of EDV (r = 0.93), ESV (r = 0.93), LVEF (r = 0.83) and LVMM (r = 0.72). CONCLUSION: ECG-gated Tc-SPECT and FDG-PET using two tracers with different characteristics (perfusion versus metabolism) showed close agreement concerning measurements of left ventricular volumes, contractile function and myocardial mass by using a model-based analysis.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Fluordesoxiglucose F18 , Volume Sistólico , Tecnécio , Disfunção Ventricular Esquerda/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tecnécio/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Disfunção Ventricular Esquerda/metabolismo
4.
Int J Cardiovasc Imaging ; 32(5): 833-43, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26883433

RESUMO

For cardiac regenerative therapy intramyocardial catheter guided cell transplantations are targeted to the infarct border zone (IBZ) i.e. the closest region of viable myocardium in the vicinity of the infarct area. For optimal therapeutic effect this area should be accurately identified. However late gadolinium enhanced magnetic resonance imaging (LGE-MRI) is the gold standard technique to determine the infarct size and location, electromechanical mapping (EMM) is used to guide percutaneous intramyocardial injections to the IBZ. Since EMM has a low spatial resolution, we aim to develop a practical and accurate technique to fuse EMM with LGE-MRI to guide intramyocardial injections. LGE-MRI and EMM were obtained in 17 pigs with chronic myocardial infarction created by balloon occlusion of LCX and LAD coronary arteries. LGE-MRI and EMM datasets were registered using our in-house developed 3D CartBox image registration software toolbox to assess: (1) the feasibility of the 3D CartBox toolbox, (2) the EMM values measured in the areas with a distinct infarct transmurality (IT), and (3) the highest sensitivity and specificity of the EMM to assess IT and define the IBZ. Registration of LGE-MRI and EMM resulted in a mean error of 3.01 ± 1.94 mm between the LGE-MRI mesh and EMM points. The highest sensitivity and specificity were found for UV <9.4 mV and bipolar voltage <1.2 mV to respectively identify IT of ≥5 and ≥97.5 %. The 3D CartBox image registration toolbox enables registration of EMM data on pre-acquired MRI during the EMM guided procedure and allows physicians to easily guide injections to the most optimal injection location for cardiac regenerative therapy and harness the full therapeutic effect of the therapy.


Assuntos
Imageamento Tridimensional , Imagem Cinética por Ressonância Magnética , Imagem Multimodal/métodos , Infarto do Miocárdio/cirurgia , Miocárdio/patologia , Transplante de Células-Tronco/métodos , Cirurgia Assistida por Computador/métodos , Animais , Área Sob a Curva , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Fibrose , Interpretação de Imagem Assistida por Computador , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Valor Preditivo dos Testes , Curva ROC , Regeneração , Sus scrofa , Fatores de Tempo , Sobrevivência de Tecidos
5.
Circulation ; 104(9): 1005-11, 2001 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-11524393

RESUMO

BACKGROUND: The aim of this prospective study was to investigate the concordance between quantitative resting (201)Tl uptake as an established myocardial viability index and the electrical activity of the heart, determined by NOGA nonfluoroscopic electroanatomic mapping. METHODS AND RESULTS: The myocardial resting and late resting thallium uptakes of 384 myocardial segments from 32 patients (27 males aged 65+/-8 years) with previous myocardial infarction and chronic stable angina were compared with unipolar voltage potentials and local shortening of the left ventricle as assessed by electroanatomic mapping. The quantitative thallium uptake data were analyzed by polar map analysis by division into 12 comparable myocardial segments, as represented in electroanatomic mapping images. Unipolar voltage potentials exhibited a significant logarithmic correlation with both resting and late resting thallium uptake (attenuation corrected: r=0.660 and r=0.744; non-attenuation corrected: r=0.623 and r=0.721). Receiver operator characteristic analyses revealed unipolar voltage cutoff points of 12.0 mV (predictive accuracy 0.853, P< 0.001; sensitivity/specificity 81%) for normal myocardium and 6.4 mV (predictive accuracy 0.901, P< 0.001; sensitivity/specificity 82%) for nonviable myocardium assessed by attenuation-corrected (201)Tl late resting images and of 12.7 mV (predictive accuracy 0.822, P<0.001; sensitivity/specificity 75%) and 6.5 mV (predictive accuracy 0.808, P<0.001; sensitivity/specificity 73%) for non-attenuation-corrected late resting (201)Tl images. CONCLUSIONS: These results indicate that the unipolar voltage potentials obtained by electroanatomic mapping correlate well with standard quantitative late resting (201)Tl imaging for the evaluation of myocardial viability; thus, NOGA endocardial mapping provides useful "online" data at the time of catheterization, especially when information from other methods for viability assessment is unavailable.


Assuntos
Cateterismo Cardíaco , Técnicas Eletrofisiológicas Cardíacas/métodos , Coração/diagnóstico por imagem , Adulto , Endocárdio/diagnóstico por imagem , Endocárdio/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Radioisótopos de Tálio
6.
J Am Coll Cardiol ; 35(6): 1580-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10807464

RESUMO

OBJECTIVES: The aim of this study was to perform an investigation of the effects of the longitudinal straightening of coronary arteries by stents and the possible association with major adverse cardiac events (MACE) (primary end point) and angiographic restenosis (secondary end point). BACKGROUND: Stent deployment straightens a tortuous artery, and any consequent arterial longitudinal stretch may contribute to MACE and stent restenosis severity. METHODS: Clinical, qualitative and quantitative angiographic data on 404 patients with single stent implantation were subjected to multivariate nominal logistic regression analysis for the prediction of MACE. The predictive accuracy, sensitivity and specificity values and cut-off points of the continuous variables were determined via receiver operating characteristics curves. The longitudinal straightening effect of stents was characterized through the changes in vessel angle (defined by the tangents to the proximal and distal parts of the stenoses/stents). RESULTS: Follow-up angiography on 354 patients revealed 73 cases of stent restenosis (> or =50% diameter stenosis). Coronary bypass surgery was performed in 4 patients and repeated percutaneous transluminal coronary angioplasty in 56 patients; acute myocardial infarction (AMI) occurred in 2 patients, and 4 patients died during the follow-up. The overall incidence of MACE (death, AMI and revascularization) was 16.3% (66 patients). The best predictive accuracies and sensitivities/specificities of factors indicative of MACE were found for the minimal lumen diameter (MLD) at follow-up (predictive accuracy: 0.9305, sensitivity/specificity: 86.6%), the post-stent MLD (0.773, 77.2%), the percent diameter stenosis (%DS) at follow-up (0.9432, 87.1%), the prestent vessel angulation (0.6797, 68.2%) and the poststent changes in vessel angulation (0.6279, 62.2%). Multivariate nominal logistic regression analysis demonstrated that a poststent MLD < or =2.63 mm (p = 0.0017, odds ratio [OR] = 17.961, 95% confidence interval [CI] = 17.45-20.428), an MLD at follow-up < or =1.7 mm (p = 0.0059, OR = 11.880, 95% CI = 11.490-14.093), a %DS at follow-up > or =42.2% (p = 0.0000, OR = 49.553, 95% CI = 48.024-53.507), a prestent vessel angulation > or =33.5 degrees (p = 0.0477, OR = 5.404, 95% CI = 5.382-7.142) and poststent changes in vessel angulation > or =9.1 degrees (p = 0.0026, OR = 19.161, 95% CI = 18.562-21.750) were significant predictors for MACE. Multiple linear regression revealed that the poststent MLD (multivariate p = 0.0001), the MLD at follow-up (p = 0.0000), the prestent vessel angulation (p = 0.0431) and the changes in vessel angulation after stent implantation (p = 0.0316) were significant independent variables predicting angiographic stent restenosis severity. CONCLUSIONS: The longitudinal straightening effect of coronary artery stents contributes significantly to the occurrence of MACE and angiographic restenosis, and this finding may have an impact on future stent design.


Assuntos
Angioplastia Coronária com Balão , Angiografia Coronária , Doença das Coronárias/terapia , Stents , Idoso , Causas de Morte , Ponte de Artéria Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , Recidiva , Fatores de Risco , Taxa de Sobrevida
7.
J Am Coll Cardiol ; 36(6): 1860-9, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11092657

RESUMO

OBJECTIVES: The goal of this study was to investigate the association between the atherosclerotic arterial remodeling and the incidence of cardiac events after coronary interventions in patients with stable angina. BACKGROUND: The local mode of de novo atherosclerotic remodeling is associated with plaque vulnerability and clinical symptoms. It may, therefore, reflect plaque morphology influencing the long-term outcome after coronary interventions. METHODS: Quantitative angiography and intravascular ultrasound were obtained in 244 patients with stable angina before and after single-vessel revascularization. On the basis of the lesion and the reference segment vessel size, patients were categorized into three groups (adaptive [AR], constrictive [CR] and intermediate [IR] remodeling). The lesion was analyzed for lumen, total vessel and plaque areas. Clinical follow-up was obtained at a mean period of 7.7+/-3.7 months. RESULTS: Patients with CR had a higher rate of in-hospital complications (10.9% vs. 2.9% and 2.7% in group CR vs. AR and IR, p = 0.035). In contrast, patients with AR had the highest rate of major adverse cardiac events (MACE) (44.3% vs. 25.5% in IR and 28.1% in CR, p = 0.024) with a predominance of revascularization at follow-up. Both target lesion restenosis (p = 0.036) and nontarget lesion de novo stenosis (p = 0.007) occurred more frequently in this group. Adaptive remodeling was a significant predictor of MACE in multivariate analysis. CONCLUSIONS: Adaptive remodeling is associated with a higher rate of MACE, target lesion restenosis and nontarget de novo stenosis. This finding may be due to differential responses of the adaptively remodeled vessel to revascularization and a generally accelerated course of systemic atherosclerosis.


Assuntos
Angina Pectoris/terapia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Ultrassonografia de Intervenção , Idoso , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/patologia , Angina Pectoris/cirurgia , Angioplastia Coronária com Balão , Angiografia Coronária , Ponte de Artéria Coronária , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos
8.
Am J Cardiol ; 84(6): 644-9, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10498132

RESUMO

A prospective, randomized, multicenter trial was conducted to evaluate whether high-pressure postdilation of the Wiktor stent provides short- and long-term benefits compared with the conventional low-pressure implantation technique. From June 1995 through May 1996, 181 patients were randomly assigned to either low-pressure (6 to 12 atm, group A, n = 94) Wiktor stent placement or to high-pressure postdilation (> or = 13 atm, group B, n = 87) after stent deployment. All patients were followed up clinically for 7 +/- 3 months, with an angiographic follow-up in 154 patients (85%). After stent implantation, neither minimal lumen diameter (MLD) nor percent diameter stenosis (%DS) differed significantly between the 2 groups (MLD, 2.8 +/- 0.5 vs 2.9 +/- 0.5 mm; %DS, 17 +/- 8% vs 16 +/- 9% for groups A and B, respectively). However, a trend toward a larger mean lumen diameter within the stent was observed in group B (3.3 +/- 0.6 vs 3.5 +/- 0.5 mm for groups A and B, respectively; difference between means 0.14 mm, 95% confidence interval -0.01 to 0.29, p = 0.08). Angiographic follow-up revealed similar MLD and %DS in both treatment groups (MLD, 2.1 +/- 0.7 vs 2.2 +/- 0.8 mm; %DS, 31 +/- 17% vs 30 +/- 24% for groups A and B, respectively, p = NS). Acute stent thrombosis occurred in 2 patients (1%) (1 patient in each group), and subacute thrombosis in 1 patient (0.6%) in group A. There was 1 death in group A, and target lesion restenosis (> or = 50% DS) was observed in 15% of patients with no differences between the groups. In conclusion, this study demonstrated favorable short- and long-term results of Wiktor stent implantation. Despite a trend toward additional initial lumen gain by high-pressure postdilation, this did not translate into a measurable improvement in long-term outcome.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Doença das Coronárias/terapia , Stents , Idoso , Doença das Coronárias/diagnóstico por imagem , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Estudos Prospectivos , Radiografia , Resultado do Tratamento
9.
Heart ; 82(1): 68-74, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10377312

RESUMO

OBJECTIVE: To investigate the use of intravascular ultrasound (IVUS) in detecting the presence of arterial remodelling in patients with unstable angina. DESIGN: Prospective case study. PATIENTS: 60 of 95 consecutively admitted patients with unstable angina (41 male, 19 female), mean (SD) age 61.2 (8.1) years. INTERVENTIONS: Qualitative and quantitative coronary angiography and IVUS. MAIN OUTCOME MEASURES: Adaptive or constrictive remodelling (AR, CR) was considered present when the cross sectional area of the external elastic membrane at the lesion site was larger than the proximal cross sectional area or smaller than the distal cross sectional area, respectively. RESULTS: 22 of the 60 patients (37%) showed AR and 14 (23%) showed CR. No remodelling was seen in 24 patients (group NR). The plaque contained more thrombus and plaque rupture in group AR than in groups CR and NR (thrombus: 91% v 50% and 67%, respectively, p = 0.023; rupture: 73% v 29% and 42%, p = 0.020). AR was associated with a larger plaque cross sectional area (12.6 (SD 4.6) mm2 v 10.8 (6.3) and 9.2 (3.7) mm2, p = 0.001) and larger external elastic membrane cross sectional area (16.5 (5.8) mm2 v 13.2 (5.2) and 14.4 (3.6) mm2, p = 0.01 in group AR v groups CR and NR, respectively), while the plaque burden was larger in groups AR (74.9 (9.1)%) and CR (72.4 (16.6)%) than in group NR (66.2 (18.1)%, p = 0.005). CONCLUSIONS: IVUS is capable of detecting adaptive and constrictive remodelling of target lesions and its relation to plaque morphology in unstable angina.


Assuntos
Angina Instável/patologia , Vasos Coronários/patologia , Ultrassonografia de Intervenção , Idoso , Angina Instável/diagnóstico por imagem , Angiografia Coronária , Doença da Artéria Coronariana/etiologia , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
10.
Coron Artery Dis ; 12(3): 167-72, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11352072

RESUMO

BACKGROUND: Recurrent ischemic events occur during the hospital stay of 7-32% of patients after successful thrombolytic treatment of acute myocardial infarction (AMI). OBJECTIVE: To define the association between postinfarction angina pectoris and the clinical, angiographic, and intravascular ultrasound (IVUS) parameters of the infarct-related artery for consecutive prospectively included patients. METHODS: Clinical, qualitative, and quantitative angiographic and IVUS data for 64 patients (56 men, aged 53+/-12 years) with thrombolysis of AMI were analyzed. All patients underwent coronary angiography and pre-interventional IVUS measurement electively within 1 month of AMI or at the time of the occurrence of postinfarction angina pectoris. Classification as adaptive or constrictive remodeling was according to whether the cross-sectional area of a vessel was larger or smaller than that of the proximal or distal reference segment. RESULTS: Nineteen of the 64 patients (29.7%) suffered from recurrence of ischemic events (group 1), whereas 45 patients (60.3%, group 2) remained free from symptoms. In univariate analyses, multivessel disease (42 versus 24%, P= 0.0236) and adaptive remodeling (63 versus 24%, P= 0.0032) were found to occur more commonly among patients in group 1. The patients in group 1 exhibited larger total vessel cross-sectional areas than did the patients in group 2 (17.5+/-4.2 versus 14.9+/-6.1 mm2, P = 0.0556). In multivariate regression analysis, adaptive remodeling proved to be a significant predictor (P = 0.0145) of the recurrence of ischemic events after thrombolysis of AMI. CONCLUSIONS: Adaptive remodeling of the infarct-related artery is associated with early postinfarction angina pectoris after thrombolysis of AMI.


Assuntos
Angina Pectoris/fisiopatologia , Vasos Coronários/lesões , Vasos Coronários/fisiopatologia , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Terapia Trombolítica , Adulto , Idoso , Angina Pectoris/diagnóstico por imagem , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Estudos Prospectivos , Recidiva , Ultrassonografia
11.
Coron Artery Dis ; 8(6): 335-41, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9347213

RESUMO

BACKGROUND: Vasoactive intestinal peptide (VIP) acts as a vasodilator on coronary and gastrointestinal arteries. During coronary occlusion, the locally released VIP may exert a protective effect on the heart, but it may aggravate the shock state through its vasodilatory effect in the gastrointestinal tract. METHODS: After left thoracotomy, the left circumflex coronary artery (LCx) was prepared, and a pneumatic occluder was introduced around it. After 60 min of coronary occlusion, the LCx was reperfused in six dogs (reperfusion group), while in another six the occlusion was maintained for 6 h (occlusion group). Five dogs served as sham-operated controls. The plasma concentration of VIP was determined at baseline, after the 60 min occlusion and 10 min, 3 h and 6 h after reperfusion, or 3 h and 6 h after continuous occlusion in the coronary sinus and in the femoral and portal veins. RESULTS: The plasma VIP concentrations in all three vessels were increased after 60 min of LCx occlusion. During the 6 h constant coronary occlusion, concentrations remained increased in both the coronary sinus and the portal vein, but not in the femoral vein. In the reperfusion group, 10 min after reperfusion, the plasma concentrations of VIP in all three vessels had decreased. CONCLUSIONS: Coronary artery occlusion causes a long-term increase in plasma VIP concentrations that decreases after reperfusion, when measured in the portal vein and coronary sinus, but not in the femoral veins.


Assuntos
Sistema Digestório/metabolismo , Infarto do Miocárdio/sangue , Miocárdio/metabolismo , Peptídeo Intestinal Vasoativo/sangue , Animais , Biomarcadores/sangue , Pressão Sanguínea , Vasos Coronários , Modelos Animais de Doenças , Cães , Frequência Cardíaca , Infarto do Miocárdio/patologia , Reperfusão Miocárdica , Radioimunoensaio , Vasodilatação/fisiologia
12.
Coron Artery Dis ; 10(4): 211-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10376199

RESUMO

BACKGROUND: The risk of plaque disruption and subsequent thrombosis in patients with unstable angina depends on the plaque type and size. DESIGN: Intravascular ultrasound (IVUS) was employed to illustrate the correlation between risk factors and plaque morphology in patients with unstable angina. METHODS: In a prospective study of 60 of 95 patients consecutively admitted with unstable angina [41 men, aged 61.2 +/- 8.1 years (mean +/- SD)], qualitative (soft and hard plaque, thrombus, calcification, eccentricity, adaptive and constrictive remodeling) and quantitative [lumen, external elastic membrane (EEM) and plaque cross-sectional area (CSA) and plaque burden] IVUS data relating to the target lesion, and proximal and distal reference segments were analyzed and correlated with risk factors. Univariate and multivariate nominal logistic regression analyses and analyses of variance were used to determine the independent predictors for IVUS morphology. RESULTS: For plaque composition univariate analysis showed a younger age (< 60 years) to be a predictor for adaptive remodeling (P = 0.019), and an older age to be a predictor for constrictive remodeling (P = 0.021). Hypercholesterolemia, smoking and sex were associated with a higher frequency of thrombus (P = 0.044, 0.038 and 0.043, respectively). Multivariate analyses revealed that only younger and older ages were independent predictors for adaptive and constrictive remodeling (P = 0.039 and P = 0.045). For plaque size, univariate and multivariate analyses demonstrated that diabetes mellitus and hypercholesterolemia were independent predictors for greater plaque (13.5 +/- 5.72 versus 10.17 +/- 4.6 mm2, P = 0.015, for diabetic versus non-diabetic patients; 12.0 +/- 5.35 versus 9.03 +/- 3.76 mm2, P = 0.010, for hypercholesterolemic versus normocholesterolemic patients) and EEM CSA (17.16 +/- 5.81 versus 14.3 +/- 5.1 mm2, P = 0.033, for diabetic versus non-diabetic patients; 16.57 +/- 5.49 versus 12.25 +/- 3.8 mm2, P = 0.001, for hypercholesterolemic versus normocholesterolemic patients) at the target lesion. Hypercholesterolemia was associated with significantly greater plaque and EEM CSA in both proximal and distal reference segments. CONCLUSIONS: Multivariate analyses indicated that age, diabetes and hypercholesterolemia are independent predictors for plaque morphology in patients with unstable angina.


Assuntos
Angina Instável/fisiopatologia , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Idoso , Angina Instável/patologia , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Interpretação Estatística de Dados , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Hipercolesterolemia/fisiopatologia , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Fumar/fisiopatologia , Ultrassonografia de Intervenção
13.
Int J Cardiol ; 56(2): 159-61, 1996 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-8894787

RESUMO

The plasma levels of vasoactive intestinal peptide in peripheral vein were measured in human acute myocardial infarction. The plasma vasoactive intestinal peptide level was increased within 1 h after the onset of the symptoms of acute myocardial infarction (Group 1, n = 9), compared with normal values (6.3 +/- 0.7 vs. 2.8 +/- 0.9 pg/ml, P < 0.05). Two or more hours after the onset of acute myocardial infarction there was no subsequent increase in peripheral plasma vasoactive intestinal peptide levels (n = 26). Ten days after the onset of acute myocardial infarction, the elevated plasma vasoactive intestinal peptide levels in Group 1 had normalized (3.5 +/- 0.5 pg/ml).


Assuntos
Infarto do Miocárdio/sangue , Peptídeo Intestinal Vasoativo/sangue , Idoso , Pressão Sanguínea , Ecocardiografia , Eletrocardiografia , Feminino , Seguimentos , Frequência Cardíaca , Humanos , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Fatores de Tempo , Veias
14.
Nucl Med Commun ; 15(8): 593-603, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7970441

RESUMO

The aim of this study was to evaluate and validate a new quantification method for 99Tcm-sestamibi single photon emission computed tomographic (SPECT) myocardial imaging based on a four-slice analysis method and to check the functional results of percutaneous transluminal coronary angioplasty (PTCA). Using the calculated pathological area of the scintigram as an index for myocardial ischaemia, the overall sensitivity was 81-90% and the overall specificity was 74-98%. Analysis of variance of the repeated measurements revealed good reproducibility (coefficient of variation 8.4%). A significant correlation was found between the size of the exercise-induced perfusion defects and the degree of coronary stenosis. The comparison of radionuclide ventriculography and the perfusion image in 27 patients revealed a good correlation between the resting global ejection fraction and myocardial perfusion, but there was no correlation during exercise, indicating a dissociation between myocardial perfusion and function during exercise conditions in patients with coronary artery disease (CAD). Patients with total coronary occlusions showed more resting defects than patients with partial stenoses. Both groups benefit from PTCA or re-opening of chronic coronary occlusion, respectively. Exercise-induced myocardial ischaemia significantly decreased, and in 36% of the patients with previous myocardial infarction a significant reduction of the size of the resting perfusion defects occurred. In conclusion, our quantification method is suitable for the accurate non-invasive diagnosis of CAD, and for the follow-up of the invasive treatment of coronary artery stenoses and occlusions.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Coração/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Teste de Esforço , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/terapia , Valor Preditivo dos Testes
15.
Clin Cardiol ; 23(7): 507-15, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10894439

RESUMO

BACKGROUND: Intravascular ultrasound (IVUS) predictors of native culprit lesion morphology for occurrence of major adverse cardiac events (MACE) have not been reported. Moreover, the published data on IVUS predictors of restenosis include patients with stable and unstable angina, although the development and progression of atherosclerosis related to unstable coronary syndrome is different from that of stable angina. HYPOTHESIS: This study investigated whether IVUS-derived qualitative and quantitative parameters of native (preangioplastic) plaque morphologic features can predict major adverse cardiac events in patients with unstable angina. METHODS: Clinical (age, gender, coronary risk factors), qualitative and quantitative angiographic (lesion localization, morphology, pre- and postangioplastic minimal lumen diameter, reference diameter, and percent diameter stenosis), and IVUS variables (soft/fibrocalcific plaque, calcification, presence of thrombus or plaque disruption, different types of arterial remodeling, pre- or postangioplastic minimal lumen, external elastic membrane and plaque cross-sectional area, and plaque burden of the target lesion and reference segments) were analyzed by regression analyses using the Cox model, assuming proportional hazards. RESULTS: Of 60 consecutively enrolled patients, 21 suffered from MACE, while 39 remained event-free during the followup period. Multivariate regression analyses revealed that the presence of adaptive remodeling [p = 0.0177, risk ratio (RR) = 3.108, with 95% confidence interval (CI) = 1.371-8.289] and the preangioplastic lumen cross-sectional area (p = 0.0130, RR = 0.869, with 95% CI = 0.667-0.913) are independent predictors of MACE during follow-up, as is postangioplastic angiographic minimal lumen diameter (p = 0.0330, RR = 0.715 with 95% CI = 0.678-0.812). CONCLUSIONS: Adaptive remodeling and preangioplastic lumen cross-sectional area determined by IVUS and postangioplastic minimal lumen diameter calculated by quantitative angiography are significant independent predictors of time-dependent MACE in patients with unstable angina.


Assuntos
Angina Instável/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Ultrassonografia de Intervenção , Angina Instável/etiologia , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prognóstico , Recidiva , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
16.
Orv Hetil ; 138(30): 1897-901, 1997 Jul 27.
Artigo em Húngaro | MEDLINE | ID: mdl-9289688

RESUMO

Under physiological conditions, the pancreas scarcely influences the function of the cardiovascular system, although the hormones produced in the healthy pancreas (insulin, glucagon and somatostatin) affect the myocardial contractility in pharmacological doses. Among the diseases of the pancreas, the pancreatic tumours (insulinoma, glucagonoma and vipoma), furthermore the acute and chronic pancreatitis involve cardiovascular complications, which influence the outcome of the disease. Although the clinical picture is dominated by the metabolic changes of the excessively produced hormones in pancreatic tumours, the cardiac and vascular effects of the hormones may be considerable. In acute necrotizing pancreatitis, enzymes released from the pancreas and inflammatory mediators transform acute necrotizing pancreatitis into "multiple organ disease"; one of the important forms of this disease is the cardiovascular shock syndrome. One of the best-known complications of chronic pancreatitis is the pancreoprive diabetes mellitus, and beside that other, nonspecific cardiac alterations (e.g. ECG-changes) may occur.


Assuntos
Doenças Cardiovasculares/etiologia , Hormônios Pancreáticos/fisiologia , Neoplasias Pancreáticas/complicações , Pancreatite/complicações , Doenças Cardiovasculares/diagnóstico por imagem , Doença Crônica , Angiopatias Diabéticas/etiologia , Ecocardiografia , Eletrocardiografia , Humanos
17.
Orv Hetil ; 136(29): 1539-44, 1995 Jul 16.
Artigo em Húngaro | MEDLINE | ID: mdl-7637970

RESUMO

An echocardiographic follow-up of 25 patients (pts) was performed, after the first examinations in 1978-1979. 15 pts have died in the last 15 years (Group 1), while 10 still living (Group 2). In Group 1 either the impaired global left ventricular at the time of the first echocardiography predicted a high mortality i.e. there were only two pts with normal echocardiographic findings. The other 6 acromegalic pts with a "normal heart" have survived. The left ventricular hypertrophy of pts in Group 2 was observed to increase during the 15-year follow-up, because of the development of systemic hypertension. In conclusion, the echocardiographic findings are of a good predictive value in estimations of the survival rate in acromegalic pts.


Assuntos
Acromegalia/complicações , Ecocardiografia , Acromegalia/diagnóstico por imagem , Acromegalia/mortalidade , Adulto , Feminino , Seguimentos , Humanos , Hungria/epidemiologia , Hipertensão/complicações , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
18.
J Thromb Haemost ; 9(12): 2361-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21929513

RESUMO

BACKGROUND: Even although time to treatment has been shown to be a determinant of mortality in primary angioplasty, the potential benefits are still unclear from early pharmacological reperfusion by glycoprotein (Gp) IIb-IIIa inhibitors. Therefore, the aim of this meta-analysis was to combine individual data from all randomized trials conducted on upstream as compared with late peri-procedural abciximab administration in primary angioplasty. METHODS: The literature was scanned using formal searches of electronic databases (MEDLINE and EMBASE) from January 1990 to December 2010. All randomized trials on upstream abciximab administration in primary angioplasty were examined. No language restrictions were enforced. RESULTS: We included a total of seven randomized trials enrolling 722 patients, who were randomized to early (n = 357, 49.4%) or late (n = 365, 50.6%) peri-procedural abciximab administration. No difference in baseline characteristics was observed between the two groups. Follow-up data were collected at a median (25th-75th percentiles) of 1095 days (720-1967). Early abciximab was associated with a significant reduction in mortality (primary endpoint) [20% vs. 24.6%; hazard ratio (HR) 95% confidence interval (CI) = 0.65 (0.42-0.98) P = 0.02, P(het) = 0.6]. Furthermore, early abciximab administration was associated with a significant improvement in pre-procedural thrombolysis in myocardial infarction (TIMI) 3 flow (21.6% vs. 10.1%, P < 0.0001), post-procedural TIMI 3 flow (90% vs. 84.8%, P = 0.04), an improvement in myocardial perfusion as evaluated by post-procedural myocardial blush grade (MBG) 3 (52.0% vs. 43.2%, P = 0.03) and ST-segment resolution (58.4% vs. 43.5%, P < 0.0001) and significantly less distal embolization (10.1% vs. 16.2%, P = 0.02). No difference was observed in terms of major bleeding complications between early and late abciximab administration (3.3% vs. 2.3%, P = 0.4). CONCLUSIONS: This meta-analysis shows that early upstream administration of abciximab in patients undergoing primary angioplasty for ST-segment elevation myocardial infarction (STEMI) is associated with significant benefits in terms of pre-procedural epicardial re-canalization and ST-segment resolution, which translates in to significant mortality benefits at long-term follow-up.


Assuntos
Angioplastia , Anticorpos Monoclonais/uso terapêutico , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Integrina beta3/efeitos dos fármacos , Inibidores da Agregação Plaquetária/uso terapêutico , Abciximab , Anticorpos Monoclonais/farmacologia , Humanos , Fragmentos Fab das Imunoglobulinas/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Thromb Haemost ; 103(2): 450-60, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20024490

RESUMO

We investigated the protective effect of ischaemic preconditioning (IP) on the maintenance of coronary patency using on-line measurements of coronary pressures and blood flow in a closed-chest reperfused acute myocardial infarction (MI) model in pigs. Catheter-based 90-min occlusion followed by 60-min reperfusion of the left anterior descending coronary artery (LAD) was performed in anesthetised pigs (MI group). IP was applied (IP group) through two cycles of 5-min occlusion and 5-min reperfusion of the LAD before MI induction. Coronary patency was determined by measurements of coronary wedge pressure, collateral fractional flow reserve (FFRcoll), collateral pressure index (CPI) and absolute coronary blood flow (CBF). Inducible and constitutive nitric oxide synthase (iNOS/cNOS) activities and expressions were determined in the myocardium. Plasma levels of myeloperoxidase (MPO, index of activated leukocytes) and mean platelet volume (MPV, index of activated platelets) were measured. IP resulted in significantly lower levels of MPO (0.52 +/- 0.19 vs. 1.05 +/- 0.24 U/l, p<0.001) and MPV (9.1 +/- 0.6 vs. 9.6 +/- 1.0 fl, p=0.04), higher FFRcoll (0.17 +/- 0.05 vs. 0.04 +/- 0.05, p<0.001), CPI (0.13 +/- 0.05 vs. 0.02 +/- 0.05, p<0.001) and CBF (70.7 +/- 4.2 vs. 50.8 +/- 4.8 m/min, p<0.001) post-reperfusion as compared with the MI group. IP resulted in significantly higher cNOS activity and eNOS expression. Significant negative correlation was found between MPO and measures of coronary patency (FFRcoll, CPI and CBF) and cNOS activity. Moreover, cNOS activity correlated significantly with FFRcoll, CPI and CBF. In conclusion, IP attenuates the release of MPO and platelet activation, thereby contributing to the maintenance of vessel patency at microvascular level after reperfusion of the infarct-related artery.


Assuntos
Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Circulação Coronária/fisiologia , Precondicionamento Isquêmico Miocárdico/métodos , Animais , Microcirculação , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/fisiopatologia , Peroxidase/sangue , Ativação Plaquetária , Suínos , Grau de Desobstrução Vascular
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