RESUMEN
OBJECTIVE: There is growing interest in speckle tracking echocardiography-derived strain as a measure of left ventricular function in neonates. However, knowledge gaps remain regarding the effect of image acquisition and processing parameters on circumferential strain measurements. The aim of this study was to evaluate the effect of using different region of interest (ROI) widths on speckle tracking derived circumferential strain in healthy neonates. METHODS: Thirty healthy-term-born neonates were examined with speckle-tracking echocardiography in the short-axis view. Circumferential strain values were acquired and compared using two different ROI widths. Furthermore, strain values in the different vendor-defined wall layers were also compared. RESULTS: Increasing ROI width led to a decrease in global circumferential strain (GCS) in the midwall and epicardial layers, the respective decreases in strain being -23.4 ± .6% to -22.0 ± 1.1%, p < .0001 and 18.5 ± 1.7% to -15.6 ± 2.0%, p < .0001. Segmental analyses were consistent with these results, apart from two segments in the midwall. There was no statistically significant effect on strain for the endocardial layer. A gradient was seen where strain increased from the epicardial to endocardial layers. CONCLUSION: Increasing ROI width led to a decrease in GCS in the midwall and epicardium. There is an increase in circumferential strain when moving from the epicardial toward the endocardial layer. Clinicians wishing to implement circumferential strain into their practice should consider ROI width variation as a potential confounder in their measurements.
Asunto(s)
Ecocardiografía , Ventrículos Cardíacos , Humanos , Recién Nacido , Ecocardiografía/métodos , Femenino , Masculino , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Función Ventricular Izquierda/fisiología , Reproducibilidad de los Resultados , Valores de ReferenciaRESUMEN
BACKGROUND: Right upper quadrant abdominal pain and elevated cholestasis blood tests are usually associated with bacterial calculous cholecystitis. However, viral infections, such as Epstein-Barr virus (EBV) can also manifest with a similar clinical picture and is an important differential diagnosis. CASE REPORT: This case report discusses a young woman presenting to the emergency department with acute right upper quadrant abdominal pain. The initial assessment revealed a positive Murphy's sign, elevated white blood count, and a cholestatic pattern on liver function tests, leading one to suspect bacterial calculous cholecystitis and initiating antibiotic therapy. However, clinical examination also revealed tonsillar exudates and differential white blood cell count revealed monocytosis and lymphocytosis rather than a high neutrophil count. The patient tested positive for EBV. Furthermore, ultrasound and magnetic resonance imaging revealed gallbladder wall edema with no gallstones, leading one to conclude that the clinical manifestation and laboratory results were due to an EBV infection. Antibiotic therapy was ceased and the patient did not require surgical intervention. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Calculous bacterial cholecystitis usually entails antibiotic therapy and cholecystectomy. It is important to be aware of the differential diagnosis of EBV, as it usually does not require either of these and resolves spontaneously.
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Colecistitis , Colestasis , Infecciones por Virus de Epstein-Barr , Cálculos Biliares , Femenino , Humanos , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/diagnóstico , Herpesvirus Humano 4 , Colecistitis/complicaciones , Colecistitis/diagnóstico , Cálculos Biliares/complicaciones , Dolor Abdominal/etiología , Servicio de Urgencia en Hospital , Antibacterianos/uso terapéuticoRESUMEN
Whereas the electrocardiogram (ECG) changes in hypokalemia are well known, they often receive less attention than the more striking features of hyperkalemia. Furthermore, there is a need for further discussion as to the subtleties of ECG changes that can aid in the differential diagnoses. This case study presents the ECG changes of a patient with severe hypokalemia due to diarrhea. It highlights how bifid T-waves in hypokalemia can be distinguished from other conditions such as coronary artery disease or pericarditis. Furthermore, it also shows the gradual reversal of ECG changes in the same patient when potassium is normalized.
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Hiperpotasemia , Hipopotasemia , Humanos , Hipopotasemia/diagnóstico , Hipopotasemia/etiología , Electrocardiografía , Potasio , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiología , Hiperpotasemia/diagnóstico , Hiperpotasemia/etiología , Hiperpotasemia/terapiaAsunto(s)
Miocarditis , Humanos , Miocarditis/diagnóstico por imagen , Sístole , Ecocardiografía/métodosRESUMEN
Speckle tracking echocardiography is a promising method for assessment of myocardial function in fetal and neonatal hearts, but further studies are necessary to validate and optimize the settings for use in fetal cardiology. Previous studies have shown that the definition of the region of interest (ROI) affects strain values in adults. The aim of this study was to investigate how different widths of ROI influences measurements of four-chamber longitudinal systolic strain in fetuses late in pregnancy. Thirty-one singleton, healthy fetuses born to healthy mothers underwent an echocardiographic examination during gestational week 37. Speckle tracking was performed with two different settings for ROI width; the narrowest and second most narrow, provided both widths were assessed as suitable for the myocardial wall thickness of the fetus. We found an inverse correlation between the ROI width and the strain values. Four-chamber longitudinal strain changed from - 20.7 ± 3.6% to - 18.0 ± 4.4% (p < 0.001) with increasing ROI width. Further, strain decreased from the endocardium to the epicardium with multilayer measurements. Different widths of ROI influenced the strain measurements significantly in the fetal heart, comparable to what has been reported in adults. A standardization of the ROI setting could improve the interpretation, and reduce variability in fetal strain measurements.
RESUMEN
The aims of this study was to assess the effect of using a four chamber versus a three plane model on speckle tracking derived global longitudinal strain, the effects of drift compensation, the effect of assessing strain in different layers and finally the interplay between these aspects for the assessment of strain in neonates. Speckle tracking derived longitudinal strain was obtained from 22 healthy neonates. ANOVA, Bland-Altman analyses, coefficients of variation and assessment of intraclass correlation coefficients were conducted to assess the effect of the abovementioned aspects as well as assess both inter-observer and intra-observer variability. Neither the use of the three plane model versus the four chamber model nor the use of drift compensation had a substantial effect on global longitudinal strain (less than 1%, depending on which layer was being assessed). A gradient was seen with increasing strain from the epicardial to endocardial layers, similar to what is seen in older subjects. Finally, drift compensation introduced more discrepancy in segmental strain values compared to global longitudinal strain. Global longitudinal strain in healthy neonates remains reasonably consistent regardless of whether the three plane or four chamber model is used and whether drift compensation is applied. Its value increases when one moves from the endocardial to the epicardial layer. Finally, drift compensation introduces more discrepancy for regional measures of longitudinal strain compared to global longitudinal strain.
Asunto(s)
Ecocardiografía , Endocardio , Anciano , Endocardio/diagnóstico por imagen , Humanos , Recién Nacido , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Reproducibilidad de los ResultadosRESUMEN
Clinical application of strain in neonates requires an understanding of which image acquisition and processing parameters affect strain values. Previous studies have examined frame rate, transmitting frequency, and vendor heterogeneity. However, there is a lack of human studies on how user-regulated spatial and temporal smoothing affect strain values in 36 neonates. This study examined nine different combinations of spatial and temporal smoothing on peak systolic left ventricular longitudinal strain in 36 healthy neonates. Strain values were acquired from four-chamber echocardiographic images in the software-defined epicardial, midwall, and endocardial layers in the six standard segments and average four-chamber stain. Strain values were compared using repeated measure ANOVAs. Overall, spatial smoothing had a larger impact than temporal smoothing, and segmental strain values were more sensitive to smoothing settings than average four-chamber strain. Apicoseptal strain decreased by approximately 4% with increasing spatial smoothing, corresponding to a 13-19% proportional change (depending on wall layer). Therefore, we recommend clinicians be mindful of smoothing settings when assessing segmental strain values.
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Ecocardiografía/métodos , Ventrículos Cardíacos/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Endocardio/diagnóstico por imagen , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Recién Nacido , Masculino , Reproducibilidad de los Resultados , Programas Informáticos , Sístole , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular IzquierdaRESUMEN
Reference values for left ventricular systolic strain in healthy neonates are necessary for clinical application of strain. The objectives of this systematic review were to identify echocardiographic studies that presented left ventricular strain values in healthy neonates, perform a meta-analysis for speckle tracking-derived global longitudinal strain, and identify areas that require further investigation. A structured search was applied to MEDLINE, Embase, and Cochrane Central Register of Clinical Trials in search of echocardiographic studies that presented left ventricular strain in healthy neonates. 244 studies were identified, of which 16 studies including speckle tracking and tissue Doppler strain in the longitudinal, radial, and circumferential directions passed the screening process. Out of these 16 studies, a meta-analysis was performed on the 10 studies that reported speckle tracking global longitudinal strain. Mean speckle tracking-derived global longitudinal strain was 21.0% (95% Confidence Interval 19.6-22.5%, strain given as positive values). When the studies were divided into subgroups, mean speckle tracking global longitudinal strain from the four-chamber view was 19.5% (95% Confidence Interval 18.0-21.0%) and that derived from all three apical views was 22.5% (95% CI 20.6-24.7%), indicating that global longitudinal strain from the four-chamber view is slightly lower than global longitudinal strain from all three apical views. Neonatal strain values were close to strain values in older subjects found in previous meta-analyses. Further studies are recommended that examine strain rate, segmental strain values, strain derived from short axis views, and strain in the first few hours after birth.
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Ventrículos Cardíacos/diagnóstico por imagen , Función Ventricular Izquierda/fisiología , Ecocardiografía/normas , Femenino , Humanos , Recién Nacido , Masculino , Valores de Referencia , Reproducibilidad de los ResultadosRESUMEN
The purpose of this study was to investigate the effect of frame rate and probe frequency on the accuracy of speckle tracking echocardiography-derived strain measurements in infants. An infant-sized left ventricle phantom with sonomicrometer crystals was made from polyvinyl alcohol. The examined stroke rates were 60, 120 and 180 strokes per min (SPM). Longitudinal strain and circumferential strain measurements were analyzed from a total of 1860 cine loops. These cine loops were acquired using two pediatric probes of different frequencies at both fundamental and harmonic imaging modes. Both probes were examined at different settings (in total, 30 different frame rate-frequency combinations). At optimal settings, both longitudinal and circumferential strain displayed high accuracy. Frequency settings did not have a consistent effect on accuracy, while low frame rates led to less accurate measurements. We recommend a frame rate/heart ratio >1 frame per second/beats per min, especially for circumferential strain.