RESUMEN
OBJECTIVES: We validated a novel image-based motion estimation computed tomographic (CT) technique (iME) to quantify atrial regional function in swine in vivo. MATERIALS AND METHODS: Domestic swine (n = 8) underwent CT scan with intravenous contrast before and after median sternotomy where 15 to 30 glass beads were sutured to the atria to calculate the motion estimation error. Four-dimensional motion vector field was estimated using iME. Area change ratio (%AC) was calculated over the atrial endocardium to assess the surface deformation. RESULTS: The error between the measured and the calculated coordinates based on motion vector field was 0.76 ± 0.43 mm. The %AC was regionally heterogeneous. The %AC time course was significantly different between the right and the left atriums (P < 0.001) as well as between the right atrial appendage and the right atrial chamber (P = 0.004). CONCLUSIONS: Quantitative assessment of atrial regional function using iME is highly accurate. Image-based motion estimation computed tomographic (CT) technique can quantify subtle regional dysfunction that is not apparent in global functional indices such as ejection fraction.
Asunto(s)
Algoritmos , Función Atrial/fisiología , Atrios Cardíacos/diagnóstico por imagen , Imagenología Tridimensional/métodos , Movimiento/fisiología , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Flujo Sanguíneo Regional/fisiología , Tomografía Computarizada por Rayos X/métodos , Animales , Femenino , Movimiento (Física) , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , PorcinosRESUMEN
A subset of patients with severe airway disease cannot be adequately supported with conventional mechanical ventilation during complex airway procedures. We report the successful respiratory support of a patient with severe tracheobronchomalacia with venovenous extracorporeal membrane oxygenation during rigid bronchoscopy with stent removal and stent placement.