Chronic hypobaric hypoxia, patent arterial duct and a new interventional technique to close it.

BACKGROUND: Interventional closure of patent arterial duct has become an accepted alternative to surgical closure. Clinical trial with "Nit-Occlud® PDA-R". METHODS AND RESULTS: To assess the safety and efficacy of the device, we performed a prospective clinical study between June, 2009 and December, 2010 in La Paz, Bolivia. In all, 29 - 22 female patients and 7 male patients - out of 59 patients were selected on the basis of inclusion criteria. The procedures were performed under sedation at an age and weight of 5.7 years and 22.7 kilograms, respectively, with 4-6 French arterial sheaths and 5-7 French venous sheaths. The minimal diameter of the duct was 3.5 millimetres. The procedure, fluoroscopy, and hospitalisation times were 96.4 minutes (55 to 145), 13.1 minutes (3 to 25.2), and 24 hours, respectively. The "Nit-Occlud® PDA-R" was successfully deployed in all patients. Immediate, 24-hour, 1-, 3-, and 6-month closure rates were 65.5%, 79.3%, 96.5%, and 100%, respectively. The systolic pulmonary pressure diminished from 37 millimetres of mercury (21 to 57) before the intervention to 31 millimetres of mercury (21 to 45) after the intervention. No early or late embolisation, haemolysis, left pulmonary artery, or descending aorta obstruction occurred. CONCLUSIONS: We conclude that the "Nit-Occlud® PDA-R" device is safe and effective in closing patent arterial duct up to a diameter of 8 millimetres.

Angioplastía percutánea en coartación aortica / Pecutaneous angiioplasty in aortic coarttation

Experiencia local en la técnica de angioplastía con catéter-balón, realizada en siete pacientes con edad que oscila entre 1 mes a 27 años, siendo 5 varones y 2 mujeres, con diagnostico de coartación aórtica nativa. Una vez realizada la sedación, se colocó un introductor en la arteria femoral y se procedió al avance de guías y catéteres hasta la aorta transversa, con el objetivo de obtener imágenes angiografícas y medir presiones invasivas en todos los segmentos. El gradiente de presión pre intervención fue de 41.5mmHg en promedio (rango:21-69mmHg) disminuyó post intervención a 10mmHg en promedio (rango:0-20mmHg). El diámetro de la coartación pre dilatación en promedio fue de 4.3mm (rango: 2.3 a 9.4mm) y aumentó post dilatación a 8.4 mm (rango: 5.5 a 13.5mm). El resultado final fue satisfactorio, pues disminuyó significativamente el gradiente de presión, el diámetro aórtico coartado aumentó y los pulsos en las cuatro extremidades se tornaron simétricos. Se alcanzó estabilidad clínica y el procedimiento se demostró como favorable en todos los pacientes. Los controles postintervención hasta un año después mostraron que el gradiente se mantiene en el tiempo, salvo en el caso de la niña de un mes, que desarrolló recoartación aórtica y fue operada en condiciones electivas, como es usual para este grupo de edad.

Local experience in the technique of balloon catheter angioplasty, performed in seven patients aged between 1 month and 27 years, 5 males and 2 females, diagnosed with native aortic coarctation. After the sedation, the introducer was collocated in the femoral artery, and guide wires and catheters were pushed forward until the transverse aorta in order to obtain angiographic images and to measure invasive pressures in all the segments. The mean pressure gradient before the intervention was 41.5mmHg (range:21-69mmHg) and decreased post intervention to 10mmHg (range:0-20mmHg). The mean diameter of the coarctation pre dilatation was 4.3mm (range:2.3-9.4mm) and increased post dilation to 8.4mm(range:5.5-13.5mm). The final result was satisfactory because the pressure gradient was significantly reduced, the aortic diameter increased and the pulses in all four extremities symmetrical. Clinical stability was achieved and the procedure proved to be favorable for all the patients. Controls until one year post intervention showed that the gradient did not change over the time, except in the case of a one month old girl, who developed recoarctation and was operated in elective conditions, as it is usual for this group of age.