ABSTRACT
Objective. To validate the utility of 4D Blood Flow and Navier-Stokes equations to create relative pressure (RP) maps in the aorta and pulmonary artery (PA) in healthy volunteers and patients with repaired tetralogy of Fallot (TOF). Methods. A 4D flow sequence of whole heart and its major vessels was acquired in 10 healthy volunteers and 6 patients with repaired TOF. The root of the ascending aorta was used as the reference point to calculate RP along five different points of this area. In addition, relative pressure of both right and left PA was measured as correlated to absolute pressure. Results. Patients with repaired TOF showed greater pulmonary artery (PA) relative pressure differences between maximum and minimum values when compared to volunteers (p <0.05). Additionally, aortic relative pressures had an excellent correlation with published data, whether using 4D flow or by catheterization. Conclusions. 4D Flow MRI may represent a new non-invasive and non operator-dependent diagnostic tool in CV disease management.
Objetivo. Utilizar 4D Flow y las ecuaciones de Navier-Stokes para obtener mapas de presiones relativas (PR) en la Aorta y Arteria Pulmonar (AP) de voluntarios y pacientes con Tetralogía de Fallot reparada (TOFr). Métodos. En 10 voluntarios y 6 pacientes con TOFr se adquirió la secuencia 4D flow del corazón y sus principales vasos. La raíz de la Aorta Ascendente se utilizó como referencia para calcular las PR a esta zona en cinco puntos distintos. Además, se midió la PR de la AP derecha e izquierda respecto a la AP. Resultados. Los pacientes con TOFr tuvieron diferencias de PR entre los valores máximos y mínimos más grandes que los voluntarios en la AP (p<0,05). Adicionalmente, las PR de la aorta tuvieron una excelente correlación con datos publicados utilizando 4D flow y mediante cateterización. Conclusiones. 4D Flow podría constituir una nueva herramienta diagnóstica, no invasiva, ni operador dependiente, en el manejo de patologías CV.
Subject(s)
Middle Aged , Aorta, Thoracic/physiopathology , Pulmonary Artery/physiopathology , Magnetic Resonance Imaging , Tetralogy of Fallot/physiopathology , Blood Flow Velocity , PressureABSTRACT
Background: Gallbladder cancer (GBC) is the first cause of death by cancer among Chilean women and mortality has not improved in the last 20 years. Aim: To study GBC mortality trend from 1985-2002, analyze risk differentials by age, sex, geographic region and accessibility to surgery. Material and Methods: Mortality data was obtained from death certificate databases. Population data was obtained from the census and biliary surgery information, from Ministry of Health registries. Standardized Mortality rates were based in the world population; trend was analyzed with point of change methods. Results: From 1985 to 2002, 27,183 GBC deaths occurred, 1,510 per year. The absolute number of deaths increased in 65% but standardized mortality rates remained unchanged at 11.3 per 100,000. These were higher among women than men (15.6 and 7.0, respectively, with a risk ratio of 2.2). Sex ratio peaked at ages 35-54 with risk ratio of 4.1. Death risk increased from North to South, peaking in poorer areas, especially in places with rural population and Mapuche ethnic admixture. Mortality appear to correlate with the rate of people waiting for gallbladder surgery, but not reaching statistical significance (r2 0.27, ns). Compared with other countries, Chile has a higher rate of GBC deaths in relation to its gross domestic product per capita. Conclusions: There is a high and persistent persistent risk for GBC in Chile, particularly among women, from the Southern regions where gallbladder surgery is insufficient for the needs, as reflected by the rates of people waiting for biliary surgery. GBC rates could be dropped by offering gallbladder surgery to everyone waiting for it and to those incident cases with gallstones.