RESUMO
Patients who present to the emergency department with chest pain but no evidence of ischemia on the electrocardiogram and negative cardiac markers are at very low risk. The newest American Heart Association/American College of Cardiology guidelines give noninvasive cardiac testing a IIa recommendation in this patient population. Here, we will review the existing literature that was cited in the American Heart Association/American College of Cardiology document, as well as several large, contemporary, comparative observational studies which were not included to address the following question: Do the benefits of noninvasive cardiac testing in this patient population outweigh the risks?
Assuntos
Dor no Peito/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Serviço Hospitalar de Emergência/normas , Teste de Esforço , Humanos , Estudos Observacionais como Assunto , Guias de Prática Clínica como AssuntoRESUMO
Cardiac resynchronization therapy (CRT) is an established treatment modality for systolic heart failure. Aimed to produce simultaneous biventricular stimulation and correct the lack of ventricular synchrony in selected patients with congestive heart failure, CRT has shown to improve mortality and reduce hospital admissions when compared to medical treatment. At present, the indication criteria for the implantation of a CRT device include an ejection fraction of less than 35%, heart failure symptoms consistent with NYHA functional class III-IV and a QRS complex duration equal or longer than 120 milliseconds. It has been reported that 30% of patients who meet those criteria still may not derive clinical benefit from CRT. Due to the existing diversity of imagin modalities and resources for their process and analysis, a great expectation in terms of more accurate diagnosis of ventricular dyssynchrony has been raised. Reilable identification of dyssynchrony could allow us to better predict the favorable response of an individual patient to CRT and therefore offer this procedure to those individuals most likely to benefit. We review the available techniques for the study of ventricular dyssynchrony for CRT patient selection and the results of its application in clinical trials. Despite tremendous progress in the imaging technology available for the assessment and diagnosis of ventricular dyssynchrony, an ideal method has not been identified and the duration of QRS complex in the surface ECG remains the accepted criteria of dyssynchrony in the selection of patients for CRT.
Assuntos
Terapia de Ressincronização Cardíaca , Seleção de Pacientes , Disfunção Ventricular/terapia , Insuficiência Cardíaca/complicações , Humanos , Ultrassonografia , Disfunção Ventricular/diagnóstico por imagem , Disfunção Ventricular/etiologiaRESUMO
Cardiac resynchronization therapy (CRT) is an established treatment modality for systolic heart failure. Aimed to produce simultaneous biventricular stimulation and correct the lack of ventricular synchrony in selected patients with congestive heart failure, CRT has shown to improve mortality and reduce hospital admissions when compared to medical treatment. At present, the indication criteria for the implantation of a CRT device include an ejection fraction of less than 35%, heart failure symptoms consistent with NYHA functional class III-IV and a QRS complex duration equal or longer than 120 milliseconds. It has been reported that 30% of patients who meet those criteria still may not derive clinical benefit from CRT. Due to the existing diversity of imaging modalities and resources for their process and analysis, a great expectation in terms of more accurate diagnosis of ventricular dyssynchrony has been raised. Reliable identification of dyssynchrony could allow us to better predict the favorable response of an individual patient to CRT and therefore offer this procedure to those individuals most likely to benefit. We review the available techniques for the study of ventricular dyssynchrony for CRT patient selection and the results of its application in clinical trials. Despite tremendous progress in the imaging technology available for the assessment and diagnosis of ventricular dyssynchrony, an ideal method has not been identified and the duration of the QRS complex in the surface ECG remains the accepted criteria of dyssynchrony in the selection of patients for CRT.
La terapia de resincronización cardiaca es una modalidad de tratamiento bien establecida para la insuficiencia sistólica cardiaca. Dirigida a producir una estimulación biventricular simultánea y a corregir la falta de sincronía ventricular en pacientes seleccionados con insuficiencia cardiaca congestiva, la terapia de resincronización cardiaca ha mostrado ser capaz de mejorar los índices de mortalidad y reducir las admisiones hospitalarias cuando se compara con el tratamiento médico. Actualmente, los criterios para la implantación de un dispositivo de terapia de resincronización cardiaca incluyen una fracción de eyección menor a 35%, síntomas de insuficiencia cardiaca consistentes con la clase funcional NYHA III-IV, y una duración del complejo QRS igual o mayor de 120 milisegundos. Se ha reportado que 30% de los pacientes que cumplen con estos criterios pueden inclusive no obtener beneficio clínico de la terapia de resincronización cardiaca. Debido a la diversidad existente de los estudios de imagenología y de los recursos para su proceso y análisis, ha surgido una gran expectativa en términos de un diagnóstico más exacto de la asincronía ventricular. La identificación confiable de la asincronía nos podría permitir predecir mejor la respuesta favorable de un paciente en particular a la terapia de resincronización cardiaca y así ofrecer este procedimiento a aquellos pacientes con mayores probabilidades de beneficiarse de dicha terapia. Hacemos una revisión de las técnicas disponibles para el estudio de la asincronía ventricular para la selección de pacientes para esta terapia y los resultados de su aplicación en pruebas clínicas. A pesar de los grandes progresos alcanzados en la tecnología de imágenes disponibles para la evaluación y diagnóstico de la asincronía ventricular, no se ha identificado un método ideal y la duración del complejo QRS en el ECG de superficie sigue siendo el criterio aceptado de asincronía en la selección de pacientes para terapia de resincronización cardiaca.
Assuntos
Humanos , Terapia de Ressincronização Cardíaca , Seleção de Pacientes , Disfunção Ventricular/terapia , Insuficiência Cardíaca/complicações , Disfunção Ventricular/etiologia , Disfunção VentricularRESUMO
A molecular epidemiologic investigation in two Brazilian states (Rondônia and São Paulo) was undertaken to determine if Ehrlichia species responsible for human and animal ehrlichioses in North America could be found in Brazilian vectors, potential natural mammalian reservoirs and febrile human patients with a tick bite history. Samples, including 376 ticks comprising 9 Amblyomma species, 29 capybara (Hydrochaeris hydrochaeris) spleens, 5 canine blood, and 75 human blood samples from febrile patients with history of tick bites were tested by a real-time PCR assay targeting a fragment of the Ehrlichia dsb gene. Ehrlichia DNA was not detected in any tick, capybara or human samples. In contrast, 4 out of 5 dogs contained Ehrlichia canis DNA in their blood, which were sequenced, representing the first report of E. canis infecting dogs in the Amazon region of Brazil. Further studies are needed to evaluate the presence of other agents of human and animal ehrlichioses in Brazil.