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1.
J Phys Chem A ; 128(7): 1241-1249, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38324399

RESUMO

The recent implementation of attosecond and few-femtosecond X-ray pump/X-ray probe schemes in large-scale free-electron laser facilities has opened the way to visualize fast nuclear dynamics in molecules with unprecedented temporal and spatial resolution. Here, we present the results of theoretical calculations showing how polarization-averaged molecular-frame photoelectron angular distributions (PA-MFPADs) can be used to visualize the dynamics of hydrogen migration in methanol, ethanol, propanol, and isopropyl alcohol dications generated by X-ray irradiation of the corresponding neutral species. We show that changes in the PA-MFPADs with the pump-probe delay as a result of intramolecular photoelectron diffraction carry information on the dynamics of hydrogen migration in real space. Although visualization of this dynamics is more straightforward in the smaller systems, methanol and ethanol, one can still recognize the signature of that motion in propanol and isopropyl alcohol and assign a tentative path to it. A possible pathway for a corresponding experiment requires an angularly resolved detection of photoelectrons in coincidence with molecular fragment ions used to define a molecular frame of reference. Such studies have become, in principle, possible since the first XFELs with sufficiently high repetition rates have emerged. To further support our findings, we provide experimental evidence of H migration in ethanol-OD from ion-ion coincidence measurements performed with synchrotron radiation.

2.
Phys Chem Chem Phys ; 25(19): 13784-13791, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37159272

RESUMO

We present a study on molecular-frame photoelectron angular distributions (MFPADs) of small molecules using circularly polarized synchrotron light. We find that the main forward-scattering peaks of the MFPADs are slightly tilted with respect to the molecular axis. This tilt angle is directly connected to the molecular bond length by a simple, universal formula. We apply the derived formula to several examples of MFPADs of C 1s and O 1s photoelectrons of CO, which have been measured experimentally or obtained by means of ab initio modeling. In addition, we discuss the influence of the back-scattering contribution that is superimposed over the analyzed forward-scattering peak in the case of homo-nuclear diatomic molecules such as N2.

3.
Phys Chem Chem Phys ; 24(44): 27121-27127, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342321

RESUMO

During the last decade, X-ray free-electron lasers (XFELs) have enabled the study of light-matter interaction under extreme conditions. Atoms which are subject to XFEL radiation are charged by a complex interplay of (several subsequent) photoionization events and electronic decay processes within a few femtoseconds. The interaction with molecules is even more intriguing, since intricate nuclear dynamics occur as the molecules start to dissociate during the charge-up process. Here, we demonstrate that by analyzing photoelectron angular emission distributions and kinetic energy release of charge states of ionic molecular fragments, we can obtain a detailed understanding of the charge-up and fragmentation dynamics. Our novel approach allows for gathering such information without the need of complex ab initio modeling. As an example, we provide a detailed view on the processes happening on a femtosecond time scale in oxygen molecules exposed to intense XFEL pulses.

4.
Inorg Chem ; 48(9): 3934-42, 2009 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-19326890

RESUMO

Full multiple scattering (FMS) Minuit XANES (MXAN) has been combined with laser pump-probe K-edge X-ray absorption spectroscopy (XAS) to determine the structure of photoexcited Ni(II)tetramesitylporphyrin, Ni(II)TMP, in dilute toluene solution. It is shown that an excellent simulation of the XANES spectrum is obtained, excluding the lowest-energy bound-state transitions. In ground-state Ni(II)TMP, the first-shell and second-shell distances are, respectively, d(Ni-N) = (1.93 +/- 0.02) A and d(Ni-C) = (2.94 +/- 0.03) A, in agreement with a previous EXAFS result. The time-resolved XANES difference spectrum was obtained (1) from the spectra of Ni(II)TMP in its photoexcited T(1) state and its ground state, S(0). The XANES difference spectrum has been analyzed to obtain both the structure and the fraction of the T(1) state. If the T(1) fraction is kept fixed at the value (0.37 +/- 0.10) determined by optical transient spectroscopy, a 0.07 A elongation of the Ni-N and Ni-C distances [d(Ni-N) and d(Ni-C)] is found, in agreement with the EXAFS result. However, an evaluation of both the distance elongation and the T(1) fraction can also be obtained using XANES data only. According to experimental evidence, and MXAN simulations, the T(1) fraction is (0.60 +/- 0.15) with d(Ni-N) = (1.98 +/- 0.03) A (0.05 A elongation). The overall uncertainty of these results depends on the statistical correlation between the distances and T(1) fraction, and the chemical shift of the ionization energy because of subtle changes of metal charge between the T(1) and S(0) states. The T(1) excited-state structure results, independently obtained without the excited-state fraction from optical transient spectroscopy, are still in agreement with previous EXAFS investigations. Thus, full multiple scattering theory applied through the MXAN formalism can be used to provide structural information, not only on the ground-state molecules but also on very short-lived excited states through differential analysis applied to transient photoexcited species from time-resolved experiments.


Assuntos
Metaloporfirinas/química , Análise Espectral/métodos , Modelos Moleculares , Estrutura Molecular , Fotoquímica , Teoria Quântica , Tolueno/química , Raios X
5.
Kyobu Geka ; 60(13): 1154-7, 2007 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-18078081

RESUMO

A 78-year-old patient with heavily calcified ascending aorta underwent mitral valve repair for mitral valve regurgitation. Chordal replacement with expanded polytetrafluoroethylene (ePTFE) loop technique was done under endo aortic clamp with a balloon catheter. He was discharged from the hospital on the 24th postoperative day without any major complications. Endo aortic clamp is thought to be a useful technique for a case with heavily calcified aorta.


Assuntos
Aorta/patologia , Valva Mitral/cirurgia , Idoso , Calcinose , Procedimentos Cirúrgicos Cardiovasculares/métodos , Humanos , Masculino , Insuficiência da Valva Mitral/cirurgia
6.
Oral Oncol ; 40(3): 314-20, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14747063

RESUMO

The aim of this study was to analyze the iodine-unstained region expanding around oral squamous cell carcinoma (SCC) by quantification of telomerase activity. The epithelial dysplasia often observed around SCC is considered to cause local recurrence or a second primary cancer. However these areas are hard to distinguish from normal mucosa. To clear the border of the expanding epithelial dysplasia around SCC, we stained with 3% iodine solution, and then decided the surgical margin. We measured quantification of telomerase activity in tumor, in epithelial dysplasia, and also in normal epithelium. Thirty-three primary cases of oral SCC which have iodine-unstained region around lesions were investigated. Fluorescense-based TRAP was applied to obtain quantification of telomerase activity. We obtained the following results: histological examination confirmed that every patient's unstained region consisted of various degrees of epithelial dysplasia. The quantified telomerase activities for squamous cell carcinoma, epithelial dysplasia and normal epithelium were 53.9, 39.6 and 2.7 U/microgP, respectively, and there was a significant difference between carcinoma and normal areas, and between dysplasia and normal epithelium. Therefore, these findings suggest that the areas of epithelial dysplasia unstained by iodine consist of cells that are nearly cancerous and excessively proliferative, and that epithelial dysplasia around SCC should be resected together with the tumor. Vital staining with iodine is useful for identifying epithelial dysplasia around SCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/enzimologia , Neoplasias Bucais/enzimologia , Lesões Pré-Cancerosas/enzimologia , Telomerase/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Epitélio/enzimologia , Epitélio/patologia , Feminino , Humanos , Iodo , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/enzimologia , Mucosa Bucal/patologia , Neoplasias Bucais/patologia , Lesões Pré-Cancerosas/patologia , Coloração e Rotulagem
7.
J Synchrotron Radiat ; 10(Pt 1): 26-42, 2003 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-12511788

RESUMO

State-of-the-art techniques for analysing X-ray absorption spectra are reviewed, with an eye to biological applications. Recent attempts to perform full spectral fitting of the XANES energy region and beyond for the purpose of structural analysis have met with encouraging success. The present paper analyses the theoretical motivations behind this success and indicates routes for future improvements. The theoretical background is not entirely new, although the point of view is, and some sections and appendices present material that the Authors believe has never been published before. The aim of this paper is to provide a theoretical analysis that is as self-contained as possible.


Assuntos
Absorciometria de Fóton/tendências , Biologia/métodos , Absorciometria de Fóton/métodos , Matemática , Modelos Teóricos , Estrutura Molecular
8.
Chest ; 120(6): 1959-63, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11742928

RESUMO

STUDY OBJECTIVE: To assess the effect of coronary flow to the infarct zone before primary coronary angioplasty on hospital complications in patients with acute myocardial infarction (MI). DESIGN: Consecutive case series analysis. SETTING: Coronary-care unit in a university hospital. PATIENTS: Two hundred sixty-four consecutive patients with ST-elevation acute MIs who had successful primary percutaneous transluminal coronary angioplasty. INTERVENTIONS: Coronary angiography on hospital admission and serial echocardiography. MEASUREMENTS AND RESULTS: The status of infarct-related artery flow before primary angioplasty was evaluated on hospital admission. Left ventricular wall motion and pericardial effusions were studied by echocardiography. One hundred ninety patients had total occlusions (Thrombolysis in Myocardial Infarction [TIMI] flow grade, 0 to 1) in the infarct-related artery (group 1), and 74 patients had antegrade flow (TIMI flow grade, 2 to 3) [group 2] before undergoing primary angioplasty procedures. When group 1 was subdivided into two groups (for the presence and absence of collateral flow), the patients with total occlusions and no collateral flow had a higher incidence of left ventricular aneurysmal wall motion (11% vs 1%, respectively; p = 0.03) and pericardial friction rub (15% vs 3%, respectively; p = 0.03) than did those in group 2. Moreover, those patients with total occlusions and no collateral flow had higher incidences of pericardial effusion (34% vs 17%, respectively; p = 0.02; and 34% vs 9%, respectively; p < 0.01) and in-hospital mortality (8% vs 1%, respectively; p = 0.04; and 8% vs 1%, respectively; p = 0.06) than did those patients in the other two groups. CONCLUSIONS: Despite successful primary angioplasty, the absence of antegrade flow in the infarct-related artery and collateral flow to the infarct zone before angioplasty resulted in a higher incidence of in-hospital complications.


Assuntos
Angioplastia Coronária com Balão , Circulação Coronária/fisiologia , Infarto do Miocárdio/terapia , Idoso , Circulação Colateral/fisiologia , Angiografia Coronária , Ecocardiografia , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Prognóstico , Fatores de Risco
9.
Am J Cardiol ; 88(9): 956-9, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11703988

RESUMO

To evaluate the relation between ST-segment analysis and microvascular reperfusion in patients with acute myocardial infarction (AMI), we studied 51 patients with first AMI who were successfully treated by percutaneous transluminal coronary angioplasty (PTCA). The lead showing the greatest ST-segment elevation on the 12-lead electrocardiogram (ECG) was serially investigated until 24 hours after PTCA. Successful reperfusion was determined by technetium-99m tetrofosmin single-photon emission computed tomography. Impaired reperfusion (group 1: < 4 change in the sum of the defect score from before to immediately after PTCA) was observed in 24 patients, and successful reperfusion (group 2) was observed in 27 patients. Although ST-segment elevation was reduced significantly at 30 minutes after PTCA in group 2 (2.2 +/- 1.4 to 1.7 +/- 1.3 mm, p = 0.01), there was no significant change in group 1 (1.9 +/- 1.9 to 2.4 +/- 1.7 mm). Ten of 14 patients (71%) with persistent ST-segment elevation (DeltaST > 0 mm change in ST segment from before to 30 minutes after PTCA > 0) were in group 1, whereas 23 of 37 patients (62%) with ST-segment resolution (DeltaST < or = 0) were in group 2. The sensitivity and specificity of persistent ST-segment elevation for predicting impaired microvascular reperfusion were 42% and 85%, respectively. Thus, persistent ST-segment elevation 30 minutes after primary PTCA was a highly specific electrocardiographic marker of impaired reperfusion in patients with AMI.


Assuntos
Angioplastia Coronária com Balão , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/terapia , Reperfusão Miocárdica , Idoso , Angiografia Coronária , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único
10.
Jpn Heart J ; 42(4): 525-31, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11693288

RESUMO

A 68-year-old Japanese woman was admitted to hospital because of chest oppression during exertion. Coronary angiography showed a coronary artery fistula with a giant aneurysm, which originated from both the left anterior descending (LAD) and right coronary arteries. We investigated coronary blood flow velocity using the Doppler guide wire technique. The coronary flow pattern showed a very prominent systolic component, whereas the diastolic flow components were nearly normal before the operation at the LAD site proximal to the coronary artery fistula. This pattern returned to normal after the operation. This report describes the relationship between the coronary steal phenomenon and coronary flow dynamics investigated directly using the Doppler guidewire technique.


Assuntos
Fístula Artério-Arterial/fisiopatologia , Aneurisma Coronário/complicações , Aneurisma Coronário/fisiopatologia , Circulação Coronária , Doença das Coronárias/fisiopatologia , Idoso , Fístula Artério-Arterial/complicações , Velocidade do Fluxo Sanguíneo , Doença das Coronárias/complicações , Feminino , Humanos , Sístole
11.
Bull Tokyo Dent Coll ; 42(2): 87-95, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11588819

RESUMO

The purpose of this study was to investigate the treatment of 190 cases of ameloblastoma in our department from 1966 to 1994. The statistical results with regard to age, sex and region agreed with those of other investigators. Thirty-five of 43 (81.4%) cases underwent enucleation in 1960s, but the sixteen of 27 (59.3%) cases underwent partial resection of mandible in 1990s. The defect of mandible was reconstructed with iliac bone grafting since 1968, grafts with a mixture of iliac blocked bone and PCBM (particulate cancellous bone and marrow) have been used since 1975. Grafting of the inferior alveolar nerve with the great auricular nerve to the defect has been performed in our department since 1977. Recently, technique involving pull-through of the inferior alveolar nerve bundle has been used in our department. When the reconstruction method for the mandible and nerve has been established, it becomes possible to operate radically and positively. Recurrence occurred in 17 cases after the primary enucleation. It is thought that the primary treatment of ameloblastoma must be as radical as possible. It appears to be necessary to observe progress and perform follow-up in cases of ameloblastoma for more than ten years, because there was one recurrence at 9 years and 4 months after the first operation. In fact, three quarters of our cases were lost to follow-up. Such losses can problems in confirming recurrence and responding rapidly.


Assuntos
Ameloblastoma/cirurgia , Neoplasias Maxilomandibulares/cirurgia , Procedimentos Cirúrgicos Bucais/métodos , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Transplante Ósseo , Criança , Feminino , Humanos , Japão , Masculino , Mandíbula/cirurgia , Nervo Mandibular/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Procedimentos Cirúrgicos Bucais/estatística & dados numéricos , Distribuição por Sexo , Nervos Espinhais/transplante
12.
J Synchrotron Radiat ; 8(Pt 2): 207-9, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11512727

RESUMO

We study the optical potential effects on the extended x-ray absorption fine structure (EXAFS) and x-ray photoelectron diffraction (XPD) spectra. For the valence electron optical potential we use a local density approximation because the charge density changes fairly slowly, whereas we use a non-local optical potential for the core electron part based on GW-approximation. In the Br K-edge EXAFS spectra the present optical potential gives rise to the phase difference and the amplitude reduction; the agreement with the experimental result is excellent. In the N-1s XPD spectra for N2/Ni(100), the spherical wave effects enhance the effects due to the optical potential.

13.
J Synchrotron Radiat ; 8(Pt 2): 210-2, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11512728

RESUMO

We develop an approximation for the non-local spin-polarized optical potential theory for atoms in solids at intermediate and high energy. The present approximation for the optical potential builds on the GW-expression. We separate the RPA polarization propagator into a core electron and a valence electron part, and can then achieve a corresponding separation of the optical potential. For the valence electron optical potential we use a local density approximation because the charge density changes fairly slowly, whereas we use a non-local optical potential for the core electron part. Both of them depend on the spin-polarization. We apply this method to electron-Fe elastic scattering in solid, and discuss the results.

14.
J Cardiol ; 38(1): 21-8, 2001 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-11496432

RESUMO

OBJECTIVES: Endothelial function in the brachial arteries is impaired in smokers. However, little is known about this condition in young adult men. The relationship between nitric oxide(NO) production and the endothelial function was investigated in young smokers and compared with non-smokers. METHODS: Flow-mediated vasodilation of the brachial artery during reactive hyperemia was examined in 10 young smokers(mean age 31 years) and 12 control subjects(mean age 28 years). The vasodilator response in the brachial artery was measured by ultrasonography, and blood samples were obtained from the right cephalic vein. Blood samples were taken at baseline, 30 sec after cuff deflation, and before and 5 min after 0.3 mg of nitroglycerin administration. Blood flow was calculated by multiplying mean flow velocity and vessel cross-sectional area. Plasma NOx(nitrate + nitrite) levels were measured, and the percentage change of NOx production(delta NOx) was calculated as follows: delta NOx(%) = [(NOx concentration at peak flow-mediated vasodilation or after 0.3 mg nitroglycerin administration) - baseline NOx concentration)] x 100/baseline NOx concentration. RESULTS: Percentage changes in diameter of the brachial artery, NOx production and delta NOx in response to nitroglycerin were not statistically different between the two groups(smokers: 27.6 +/- 8.0 mumol/l, control subjects: 34.0 +/- 8.7 mumol/l). However, percentage change of flow-mediated vasodilation during reactive hyperemia in the young smokers was significantly smaller than that in the control subjects(4.8 +/- 2.7%, 9.1 +/- 5.3%, respectively, p < 0.05). Moreover, delta NOx during reactive hyperemia in the smokers was significantly smaller than that in the control subjects(388.8 +/- 90.2%, 738.0 +/- 284.5%, respectively, p < 0.05). CONCLUSIONS: The impaired response to reactive hyperemia in young smokers might be associated with decreases in flow-dependent NO production.


Assuntos
Endotélio Vascular/fisiopatologia , Óxido Nítrico/biossíntese , Fumar/fisiopatologia , Adulto , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiologia , Humanos , Masculino , Nitroglicerina/farmacologia , Vasodilatação/fisiologia
15.
J Cardiol ; 37(6): 293-9, 2001 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-11433804

RESUMO

OBJECTIVES: Recent studies have demonstrated an association between infection with Chlamydia (C.) pneumoniae and coronary artery disease. However, the association is less clear in the Japanese population. The relationship of C. pneumoniae infection to severity of coronary atherosclerosis was investigated in patients with chronic coronary artery disease and with normal coronary arteries. METHODS: Serum levels of IgA and IgG antibodies to C. pneumoniae outer membrane complex were measured by enzyme-linked immunosorbent assay and C-reactive protein (CRP) analyses in 130 patients who underwent coronary angiography. Patients with unstable angina and recent myocardial infarction were excluded. Results were divided into three groups according to Gensini coronary score (GCS): normal (n = 19, GCS = 0); mild atherosclerosis (n = 56, GCS = 1-19); and severe atherosclerosis (n = 55, GCS > or = 20). RESULTS: Cut off indices of IgA and IgG in the atherosclerosis groups (severe: 1.53 +/- 0.72 and 1.67 +/- 0.97, mild: 1.58 +/- 0.92 and 1.42 +/- 0.86, respectively) were higher than in the normal group (1.22 +/- 0.59 and 1.28 +/- 0.82), but there were no significant differences. There were no correlations between indices of IgA and IgG, and GCS. The normal CRP group (n = 118, < 0.3 mg/dl) and the high CRP group (n = 12, > or = 0.3 mg/dl) showed no differences in IgA and IgG indices and GCS. CONCLUSIONS: Serum antibody indices against C. pneumoniae are not associated with the severity of coronary atherosclerosis in chronic stable coronary artery disease.


Assuntos
Anticorpos Antibacterianos/análise , Infecções por Chlamydophila , Chlamydophila pneumoniae , Doença da Artéria Coronariana/diagnóstico , Idoso , Proteína C-Reativa/análise , Chlamydophila pneumoniae/imunologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
16.
Eur J Nucl Med ; 28(3): 326-33, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11315600

RESUMO

To avoid the haemorrhagic risk of unnecessary thrombolysis in acute myocardial infarction (MI), early and precise diagnosis of spontaneous recanalization (SR) of the infarct-related artery is required. To clarify the accuracy of technetium-99m tetrofosmin myocardial single-photon emission tomography (SPET) in the detection of SR in patients with acute anterior MI, electrocardiography (ECG), echocardiography and 99mTc-tetrofosmin SPET imaging were performed in 49 patients with acute anterior MI before emergency coronary angiography. Defect score was calculated as the sum of the perfusion defects of each segment: from 3 (complete defect) to 0 (normal perfusion). Echocardiographic asynergic score (the sum of asynergic grades) and the greatest ST elevation of the 12-lead ECG on admission were also measured. SR was defined as Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow on emergency coronary angiography. Defect score in 11 patients with SR (9.2 +/- 3.7) was significantly lower than that in 38 patients without SR (18.5 +/- 5.0) (P < 0.001), whereas there were no significant differences in asynergic score and ST elevation between the two groups. From the receiver operating characteristic curves, the optimal cut-off points of defect score, asynergic score and ST elevation for the detection of SR were calculated to be 12, 13 and 3.5, respectively. The sensitivity and specificity of the scintigraphic defect score (91% and 89%) were significantly higher than those of the asynergic score (64% and 68%) and ST elevation (73% and 71%). Thus, 99mTc-tetrofosmin SPET imaging on admission is a very accurate method for the detection of SR in patients with acute anterior MI.


Assuntos
Coração/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Revascularização Miocárdica , Neovascularização Fisiológica/fisiologia , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária , Ecocardiografia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Perfusão , Tomografia Computadorizada de Emissão de Fóton Único
17.
Am Heart J ; 141(4): 615-20, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11275929

RESUMO

BACKGROUND: This study was designed to determine the clinical significance of ST-segment elevation in the precordial leads (leads V1 and V2) in acute Q-wave inferior wall myocardial infarction. METHODS AND RESULTS: One hundred fifty-eight consecutive patients with acute Q-wave inferior wall myocardial infarction were classified into 3 groups on the basis of the initial ST-change in V1 (group 1 = 29 patients with ST elevation, group 2 = 97 patients with ST depression, and group 3 = 32 patients with no ST-segment change). The right coronary artery was the infarct-related artery in all the patients in group 1. Although there was no significant difference between groups 1 and 2, the number of left ventricular asynergic segments was larger and the incidence of major in-hospital arrhythmias was higher in groups 1 and 2 compared with group 3. Patients in group 1 had a significantly higher incidence of proximal lesion (86%) and right ventricular infarction (69%) than the other 2 groups did. When ST elevation in leads V1 and V2 was considered, 14 of 15 patients (93%) with ST elevation only in V1 had right ventricular infarction, whereas 6 of 14 patients (43%) with ST elevation in both V1 and V2 had right ventricular infarction (P =.011). CONCLUSIONS: ST-segment elevation in V1 on admission in patients with acute Q-wave inferior wall myocardial infarction indicates a right coronary artery lesion associated with a larger infarct size and a higher incidence of major in-hospital arrhythmias.


Assuntos
Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações
18.
Clin Cardiol ; 24(12): 770-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11768740

RESUMO

BACKGROUND: Early reperfusion therapy has reduced the infarct size and mortality rate in patients with acute myocardial infarction (AMI). The occurrence of bundle-branch block in AMI is related to the amount of myocardial damage and the insult to the conduction system. HYPOTHESIS: To evaluate the clinical and angiographic factors related to the occurrence of bundle-branch block (BBB) in patients with primary percutaneous transluminal coronary angioplasty (PTCA), we investigated consecutive series of patients with their first Q-wave AMI and successful PTCA. METHODS: Coronary angiogram at the time of admission, electrocardiogram, and echocardiogram were evaluated in 279 patients with their first Q-wave AMI and successful PTCA. RESULTS: Bundle-branch block was detected in 26 patients (9%); 16 patients had transient and 10 patients had persistent block, while 16 patients had bifascicular block and 10 patients had right BBB. The patients with BBB had a significantly larger number of left ventricular asynergic segments, higher incidence of total occlusion of infarct-related artery, angiographic no reflow, and pericardial rub than those without BBB. When the multivariate analysis was performed using five clinical markers of infarct severity, angiographic no reflow (F = 20.2, p < 0.001) and total occlusion of infarct-re-lated artery (F = 4.2, p = 0.04) were found to be the significant variables related to BBB. CONCLUSIONS: Despite successful primary PTCA, absence of antegrade flow in the infarct-related artery at the onset of AMI and/or angiographic no reflow resulted in more severe transmural myocardial damage and, hence, the occurrence of BBB.


Assuntos
Angioplastia Coronária com Balão , Bloqueio de Ramo/etiologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/terapia , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Eur J Nucl Med ; 28(3): 327-33, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24623004

RESUMO

To avoid the haemorrhagic risk of unnecessary thrombolysis in acute myocardial infarction (MI), early and precise diagnosis of spontaneous recanalization (SR) of the infarct-related artery is required. To clarify the accuracy of technetium-99m tetrofosmin myocardial single-photon emission tomography (SPET) in the detection of SR in patients with acute anterior MI, electrocardiography (ECG), echocardiography and (99m)Tc-tetrofosmin SPET imaging were performed in 49 patients with acute anterior MI before emergency coronary angiography. Defect score was calculated as the sum of the perfusion defects of each segment: from 3 (complete defect) to 0 (normal perfusion). Echocardiographic asynergic score (the sum of asynergic grades) and the greatest ST elevation of the 12-lead ECG on admission were also measured. SR was defined as Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow on emergency coronary angiography. Defect score in 11 patients with SR (9.2±3.7) was significantly lower than that in 38 patients without SR (18.5±5.0) (P<0.001), whereas there were no significant differences in asynergic score and ST elevation between the two groups. From the receiver operating characteristic curves, the optimal cut-off points of defect score, asynergic score and ST elevation for the detection of SR were calculated to be 12, 13 and 3.5, respectively. The sensitivity and specificity of the scintigraphic defect score (91% and 89%) were significantly higher than those of the asynergic score (64% and 68%) and ST elevation (73% and 71%). Thus, (99m)Tc-tetrofosmin SPET imaging on admission is a very accurate method for the detection of SR in patients with acute anterior MI.

20.
J Cardiol ; 36(1): 45-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10929265

RESUMO

A 62-year-old man was referred to our hospital for investigation of abnormal electrocardiography findings. The mean frontal plane QRS axis was directed toward the right superior quadrant(-125 degrees). Terminal S waves were present in all 3 bipolar standard leads and an R wave in lead aVR. RS complex was seen in lead V1 and deep S waves in leads V2-V6. Left ventricular hypertrophy associated with asymmetrical septal hypertrophy was suspected based on transthoracic echocardiography, but the echocardiographic quality was poor. Magnetic resonance imaging revealed hypertrophic cardiomyopathy with massive wall thickening involving the right anterobasal region of the ventricular septum. Magnetic resonance imaging may provide useful information about the distribution of ventricular myocardial hypertrophy in patients with hypertrophic cardiomyopathy and unusual electrocardiography findings.


Assuntos
Cardiomiopatia Hipertrófica/patologia , Septos Cardíacos/patologia , Cardiomiopatia Hipertrófica/fisiopatologia , Eletrocardiografia , Humanos , Hipertrofia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
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