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Ictal clinical phenomenology, including aphasia, is usually associated with increased regional cerebral perfusion. We present an unusual pattern of ictal cerebral perfusion in three patients with pharmacoresistant, lesional temporal lobe epilepsy and ictal/postictal aphasia studied with prolonged video-EEG, ictal, and interictal SPECT and MRI for pre-surgical evaluation. Subtraction of ictal-interictal SPECT images co-registered with MRI (SISCOM) showed ictal hyperperfusion in the temporal epileptogenic area in all patients. In addition, hypoperfusion of Broca's area in one case, Wernicke's area in other patient, and both areas in the remaining one were observed. Ictal aphasia in these patients may be explained by functional inhibition of a primary language area, driven by the epileptogenic network. This pattern can contribute to understand the pathophysiology of some ictal signs, with an impact on the evaluation of individual surgical risks.
Assuntos
Afasia , Epilepsia do Lobo Temporal , Humanos , Epilepsia do Lobo Temporal/cirurgia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Imageamento por Ressonância Magnética/métodos , Eletroencefalografia , Afasia/etiologia , EncéfaloRESUMO
Introduction: The objective of this study was to evaluate the clinical impact PET with 18F-FDG and 11C-PIB in patients with dementia in a developing country. Methodology: Retrospective study of the patients referred for the evaluation of dementia to the only PET center in Uruguay. A total of 248 patients were identified, from which 70 patients were included based on the availability of medical history and clinical follow-up. Main outcomes included change in diagnosis, diagnostic dilemma and AD treatment. We evaluated the association of clinical outcomes with PET concordance with baseline diagnosis, diagnostic dilemma, level of education, AD pathology/Non-AD pathology (AD/Non-AD), baseline diagnosis and 11C-PIB PET result. Results: Baseline clinical diagnosis was concordant with 18F-FDG and 11C-PIB PET results in 64.7 and 77.1% of the patients, respectively. Change in diagnosis after PET was identified in 30.0% of the patients and was associated with discordant 18F-FDG (p = 0.002) and 11C-PIB (p < 0.001) PET results, previous diagnostic dilemma (p = 0.005), low education (p = 0.027), Non-AD baseline diagnosis (p = 0.027), and negative 11C-PIB PET result (p < 0.001). Only the last variable remained significant in the multivariate analysis (adjusted p = 0.038). Diagnostic dilemma decreased after PET from 15.7 to 7.1% (p = 0.11) and was associated with Non-AD diagnosis (p = 0.002) and negative 11C-PIB PET result (p = 0.003). Change in AD treatment after PET occurred in 45.7% of the patients. Conclusion: 18F-FDG and 11C-PIB PET had a significant clinical impact in terms of change in diagnosis and treatment in patients with dementia in a developing country, similar to that reported in high-income countries.
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Biomarkers are playing a progressively leading role in both clinical practice and scientific research in dementia. Although amyloid and tau biomarkers have gained ground in the clinical community in recent years, neurodegeneration biomarkers continue to play a key role due to their ability to identify different patterns of brain involvement that sign the transition between asymptomatic and symptomatic stages of the disease with high sensitivity and specificity. Both 18F-FDG positron emission tomography (PET) and perfusion single photon emission computed tomography (SPECT) have proved useful to reveal the functional alterations underlying various neurodegenerative diseases. Although the focus of nuclear neuroimaging has shifted to PET, the lower cost and wider availability of SPECT make it a still valid alternative for the study of patients with dementia. This review discusses the principles of both techniques, compares their diagnostic performance for the diagnosis of neurodegenerative diseases and highlights the role of SPECT to characterize patients from low- and middle-income countries, where special care of additional costs is particularly needed to meet the new recommendations for the diagnosis and characterization of patients with dementia.
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Resumen: Objetivo: Evaluar la disincronía mecánica ventricular izquierda (DMVI) asociada a la estimulación endocárdica prolongada del ventrículo derecho mediante el ensayo piloto de una nueva técnica de imagen en Uruguay. Métodos: Se estudiaron 12 pacientes con marcapasos implantados al menos hace un año utilizando SPECT gatillada con 99mTc-MIBI y análisis de fase en reposo. Se registraron variables clínicas, duración del QRS, tasa, modo y sitio de estimulación ventricular, presencia y extensión de infarto e isquemia, volúmenes cavitarios y FEVI en reposo. Utilizando V-Sync de Emory Cardiac Toolbox se obtuvieron desviación estándar y ancho de banda de fase en reposo (grados), comparando los individuos con FEVI ≥ y < 50% con una población control. Resultados: Los pacientes de la serie con estimulación endocárdica prolongada en el ventrículo derecho exhibieron marcada DMVI. Los pacientes con FEVI moderada/severamente disminuida (con diámetros cavitarios mayores, estimulación septal, infarto extenso o isquemia significativa) exhibieron mayor disincronía que aquellos con FEVI conservada/levemente disminuida (ancho de banda = 144.33o vs. 77.41o, p < 0.05; desviación estándar = 46.67o vs. 26.81o, p < 0.05). Conclusiones: En la cardiopatía isquémica la elevada tasa de estimulación endocárdica crónica se asocia con marcada DMVI, aun cuando la función sistólica esté conservada. El análisis de fase podría ser una herramienta válida para evaluar la disincronía asociada al infarto en pacientes con marcapasos, y aportar a la indicación oportuna del pasaje (upgrading) al modo de estimulación biventricular.
Abstract: Objetive: To evaluate left ventricular mechanical dyssynchrony (LVMD) associated with prolonged right ventricular pacing through an innovative imaging technique as a pilot study in Uruguay. Methods: A 99mTc-MIBI gated-SPECT and phase analysis was performed in 12 patients with pace-makers implanted at least one year before scintigraphy, due to advanced atrioventricular block. Clinical data, QRS duration, rate, mode and site of pacing in right ventricle, chamber diameters, presence and extension of myocardial scar and ischaemia, as well as LVEF at rest, were recorded. Using V-Sync of Emory Cardiac Toolbox, a standard deviation (PSD) and band-width (PBW) from rest phase histogram was obtained and these indexes were compared with controls in the subgroups of patients with LVEF ≥ 50% and < 50%. Results: Patients with prolonged RV endocardial pacing exhibited marked LVMD. More severe dyssynchrony was found in patients with impaired LVEF than in patients with preserved LVEF (PSD: 46.67o vs. 26.81o, P < .05; PBW: 144.33o vs. 77.41o, P < .05). Higher left ventricle diameters, extensive infarct, or significant ischaemia were found in patients with impaired LVEF. Conclusions: Chronic right ventricular pacing was invariably associated with LVMD, even when systolic function was preserved. Phase analysis could be a potentially useful technique to evaluate LMVD associated with myocardial scar in patients with pacemakers, and to decide promptly the upgrading to biventricular pacing.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estimulação Cardíaca Artificial/métodos , Função Ventricular , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Marca-Passo Artificial , Fatores de Tempo , Fenômenos Biomecânicos , Projetos Piloto , Estudos Transversais , Bloqueio Atrioventricular/diagnóstico por imagemRESUMO
Antecedentes: aunque la cineangiocoronariografía (CACG) sigue siendo el "patrón oro" diagnóstico en la enfermedad coronaria, la optimización de sus indicaciones electivas obliga a revisar sistemáticamente los resultados de los estudios funcionales de detección de isquemia. Objetivo: analizar la tasa de angiografías sin obstrucciones coronarias epicárdicas ("en blanco") de indicación electiva tras estudios funcionales. Material y método: se realizó un estudio observacional analítico y transversal, analizando las CACG electivas realizadas en 2011-2014 en el servicio de hemodinamia público del país. Se registraron variables clínicas, indicación y resultados de la interpretación angiográfica en los pacientes que fueron estudiados previamente mediante pruebas no invasivas para detección de isquemia. La ausencia de estenosis coronaria significativa fue definida como la presencia de estenosis luminal <50%. Se excluyeron las indicaciones electivas por preoperatorio de valvulopatías, disfunción sistólica severa y arritmias ventriculares, y los pacientes con antecedentes de intervencionismo coronario percutáneo o cirugía de bypass coronario. Resultados: se incluyeron los resultados de las CACG electivas en 219 pacientes con pruebas funcionales previas. La tasa de CACG "en blanco" fue de 35,62%. Las variables asociadas con la presencia de lesiones coronarias angiográficas fueron: el sexo masculino (OR=2,22, IC 95%: 1,26-3,92), la edad ³65 años (OR=2,09, IC 95%: 1,19-3,69), la diabetes (OR=2,94, IC 95%: 1,52-45,65) y un resultado funcional de moderado/alto riesgo (OR=22,99, IC 95%: 2,90-181,80). En contraposición, un resultado funcional normal/de bajo riesgo se asoció con la ausencia de lesiones angiográficas (OR=0,04, IC 95%: 0,005-0,34). La población de pacientes estudiados previamente mediante ecocardiografía de estrés fue poco representativa (5,02%). Conclusiones: en un centro universitario público de referencia la tasa de angiografías coronarias electivas "en blanco" es acorde con lo reportado en los grandes estudios multicéntricos.
Background: although coronary angiography is still the "gold standard" diagnostic of coronary artery disease, a systematic review of its elective indications after noninvasive (functional) tests is needed. Objective: to analyze through functional tests the rate of nonobstructive ("blank") elective coronary angiography (CA) in patients previously studied through noninvasive (functional) tests. Methods: we performed an observational analytic and cross-sectional study analyzing elective CA performed in 2011-2014 in a nationwide public hemodynamic service. Clinical data indications and results of angiographic interpretation were recorded in the subjects previously studied through noninvasive (functional) tests. Elective indications corresponding to preoperative evaluation of valvular disease, severe systolic dysfunction, ventricular arrhytmias, previous history of angioplasty or coronary artery bypass surgery were excluded. We defined the absence of significant coronary stenosis as those lesions determining a luminal stenosis <50%. Results: we analyzed the results of 219 functional tests. The rate of CA without significant coronary stenosis was 35,62%. Male gender (OR=2,22, IC 95%: 1,26-3,92), age >65 years (OR=2,09, IC 95%:1,19-3,69), diabetes (OR=2,94, IC 95%: 1.52-45,65) and a moderate/high risk functional test outcome (OR=22,99, IC 95%: 2,90-181,80) were positively associated with angiographic lesions. In contrast, a normal/low risk functional outcome was associated with the absence of coronary stenosis (OR=0,04, IC 95%: 0,005-0,34). The sample of patients studied through stress-ECHO was not representative (5,02%). Conclusions: in a nationwide public university center, the rate of "blank" elective coronary angiography after functional tests is similar to large international multicenter studies.
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Humanos , Masculino , Adulto , Avaliação de Resultados em Cuidados de Saúde , Angiografia Coronária/estatística & dados numéricos , Isquemia/diagnóstico , Estudos Transversais , Estudos Retrospectivos , Técnicas e Procedimentos Diagnósticos , Estudo ObservacionalRESUMO
Antecedentes: aunque la cineangiocoronariografía (CACG) sigue siendo el patrón oro diagnóstico en la enfermedad coronaria, la optimización de sus indicaciones electivas obliga a revisar sistemáticamente los resultados de los estudios funcionales de detección de isquemia. Objetivo: analizar la tasa de angiografías sin obstrucciones coronarias epicárdicas (en blanco) de indicación electiva tras estudios funcionales. Material y método: se realizó un estudio observacional analítico y transversal, analizando las CACG electivas realizadas en 2011-2014 en el servicio de hemodinamia público del país. Se registraron variables clínicas, indicación y resultados de la interpretación angiográfica en los pacientes que fueron estudiados previamente mediante pruebas no invasivas para detección de isquemia. La ausencia de estenosis coronaria significativa fue definida como la presencia de estenosis luminal <50%. Se excluyeron las indicaciones electivas por preoperatorio de valvulopatías, disfunción sistólica severa y arritmias ventriculares, y los pacientes con antecedentes de intervencionismo coronario percutáneo o cirugía de bypass coronario. Resultados: se incluyeron los resultados de las CACG electivas en 219 pacientes con pruebas funcionales previas. La tasa de CACG en blanco fue de 35,62%. Las variables asociadas con la presencia de lesiones coronarias angiográficas fueron: el sexo masculino (OR=2,22, IC 95%: 1,26-3,92), la edad ³65 años (OR=2,09, IC 95%: 1,19-3,69), la diabetes (OR=2,94, IC 95%: 1,52-45,65) y un resultado funcional de moderado/alto riesgo (OR=22,99, IC 95%: 2,90-181,80). En contraposición, un resultado funcional normal/de bajo riesgo se asoció con la ausencia de lesiones angiográficas (OR=0,04, IC 95%: 0,005-0,34). La población de pacientes estudiados previamente mediante ecocardiografía de estrés fue poco representativa (5,02%)...
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Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Angiografia Coronária/estatística & dados numéricos , Isquemia/diagnóstico , Avaliação de Resultados em Cuidados de Saúde , Estudo Observacional , Estudos Transversais , Estudos Retrospectivos , Técnicas e Procedimentos DiagnósticosRESUMO
We report two patients referred to 2 day stress-rest single photon emission computed tomography for diagnosis of ischemia who elicited a transient left bundle branch block during dipyridamole intravenous infusion. The conduction disturbance disappeared after aminophyline infusion and became permanent during follow-up. Possible mechanisms underlying this unusual phenomenon in the absence of myocardial ischemia are discussed.
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The protocols using vasodilators to induce ischemia on myocardial perfusion scintigraphy have shown a high diagnostic accuracy and a very low incidence of serious complications. However, the physiological significance and diagnostic value of various electrocardiographic changes associated with vasodilator stress has not been deeply evaluated beyond the ST-segment. Five clinical cases presenting morphological distortion of the T-wave in electrocardiographic chest leads associated with varying degrees of perfusion defects are described, discussing potential contributions of these changes to the diagnosis and quantification of myocardial ischemia in imaging studies using vasodilator stress.
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Isquemia/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Estresse Fisiológico/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Idoso , Eletrocardiografia , Feminino , Humanos , Isquemia/induzido quimicamente , Isquemia/fisiopatologia , Masculino , Pessoa de Meia-IdadeRESUMO
Los protocolos que utilizan vasodilatadores para inducir isquemia en la centellografía de perfusión miocárdica han demostrado una exactitud diagnóstica elevada e incidencia muy baja de complicaciones graves. Sin embargo, el significado fisiológico y valor diagnóstico de diversas alteraciones electrocardiográficas asociadas al estrés vasodilatador ha sido escasamente evaluado más allá del segmento ST. Describimos cinco pacientes que presentan distorsión morfológica de la onda T en derivaciones electrocardiográficas torácicas asociada a diversos defectos de perfusión, discutiendo los potenciales aportes de estos cambios al diagnóstico y cuantificación de la isquemia miocárdica en los estudios de imagen que utilizan estrés con vasodilatadores.
The protocols using vasodilators to induce ischemia on myocardial perfusion scintigraphy have shown a high diagnostic accuracy and a very low incidence of serious complications. However, the physiological significance and diagnostic value of various electrocardiographic changes associated with vasodilator stress has not been deeply evaluated beyond the ST-segment. Five clinical cases presenting morphological distortion of the T-wave in electrocardiographic chest leads associated with varying degrees of perfusion defects are described, discussing potential contributions of these changes to the diagnosis and quantification of myocardial ischemia in imaging studies using vasodilator stress.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estresse Fisiológico/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Imagem de Perfusão do Miocárdio/métodos , Isquemia/diagnóstico por imagem , Eletrocardiografia , Isquemia/fisiopatologia , Isquemia/induzido quimicamenteRESUMO
Pulmonary hypertension significantly changes biventricular anatomy and physiology, frequently evolving to clinical deterioration and right ventricular failure. The case of a woman developing atrial arrhythmias complicating dipyridamole stress in concomitance with scintigraphic "D-shaped" left ventricle is briefly reported. Although rare, our finding may suggest that nonselective vasodilators should be used with caution in this clinical setting.