Malformaciones arteriovenosas pulmonares: presentación de un caso clínico pediátrico y revisión de la literatura / Pulmonary arteriovenous malformations: presentation of a pediatric case and review of the literature

Las malformaciones arteriovenosas pulmonares (MAVP) consisten en comunicaciones directas entre el sistema arterial y el sistema venoso pulmonar, sin paso de la sangre por el lecho capilar, produciéndose un cortocircuito de derecha a izquierda extracardíaco, pueden ser congénitas o adquiridas. Algunos casos pueden ser asintomáticos, en cambio en otros pueden ocasionar diversas manifestaciones clínicas y se pueden asociar a complicaciones severas. En niños se observa una baja incidencia y son más frecuentes las formas congénitas. La MAVP se debe sospechar por las manifestaciones clínicas y las imágenes de la radiografía de tórax (RxTx) y su confirmación se realiza mediante una AngioTomografía Computada (TC) de tórax. La embolización endovascular es actualmente el tratamiento de elección, con excelentes resultados, aunque requiere de un seguimiento posterior y de un operador experimentado. Reportamos el caso de una niña que ingresó con clínica muy sugerente, incluyendo: disnea, acropaquia, cianosis periférica, e hipoxemia refractaria. Sin embargo, inicialmente el cuadro clínico fue confundido con una crisis asmática. La Angio-TC de tórax confirmó el diagnóstico y el tratamiento mediante embolización endovascular resultó exitoso.

Pulmonary arteriovenous malformations (PAVM) are communications between the arterial and the pulmonary venous system, without passage of blood through the capillary bed, causing a left to right extracardiac shunt. Some cases may be asymptomatic, while others may cause various clinical manifestations and may be associated with severe complications. In children a low incidence is observed, and congenital forms are more frequent. PAVM should be suspected by clinical manifestations and chest x-ray imaging and confirmed by chest Computed Tomography Angiography (CTA). Endovascular embolization is currently the treatment of choice, with excellent results, although it requires subsequent follow-up. We report a patient who was admitted with a very suggestive clinical history, including: dyspnea, clubbing, peripheral cyanosis, and severe hypoxemia, refractory to oxygen therapy. However, initially the clinical picture was confounded with an asthmatic crisis. CTA confirmed the diagnosis and treatment by endovascular embolization was successful.

Fístulas arteriovenosas pulmonares en un paciente pediátrico: un reporte de caso / Pulmonary arteriovenous fistulas in a pediatric patient: a case report

Las fístulas arteriovenosas pulmonares son malformaciones congénitas dadas por la comunicación directa anómala entre arterias y venas, con una incidencia mundial de 2-3 : 100 000 habitantes. La presentación es, en general, única, asintomática, y aparecen en forma incidental como hallazgo imagenológico en la adultez, y su tratamiento de elección es la embolización endovascular.Se describe la inusual presentación clínica en una paciente de 10 años, que ingresó por disnea, tos, cianosis central y cefalea. Se encontró hipoxemia persistente, hipocratismo digital, nódulos parahiliares pulmonares, gases arteriales con gradiente alvéolo-arterial aumentado. La tomografía axial computarizada de tórax de alta resolución confirmó la presencia de una malformación arteriovenosa pulmonar en la región parahiliar derecha, la cual no se asociaba con la enfermedad de Rendu-Osler-Weber. La paciente fue tratada con embolización endovascular transcutánea. Tras 1,5 años de seguimiento, no hubo recaídas. Son pocos los casos reportados de estas fístulas en la edad pediátrica

Pulmonary arteriovenous fistulas are congenital malformations due to anomalous direct communication between arteries and veins; the incidence is 2-3 : 100,000 inhabitants. This condition is usually asymptomatic and incidentally appearing in adult imaging findings. Transcutaneous endovascular embolization is the technique of choice for treatment. The unusual presentation in a 10-year-old patient is described; she was presented to the Emergency Department with dyspnea, cough, central cyanosis and headache. The examination revealed persistent hypoxemia and digital clubbing; chest X-ray with images suggestive of parahilar nodules, arterial blood gases with increased alveolar arterial gradient. The high resolution computed tomography of the thorax revealed pulmonary arteriovenous malformation in the right parahilar region not associated with Rendu-Osler-Weber disease. The patient was treated with transcutaneous endovascular embolization, and after a year and a half of follow-up there were no relapses. There are few reported cases of pulmonary arteriovenous fistulas in the pediatric age.

A case of prenatally diagnosed extrapulmonary arteriovenous malformation associated with a complex heart defect

Pulmonary arteriovenous malformations are rare vascular anomalies of the lung, only a few cases of which have been diagnosed prenatally. The diagnostic clue for prenatal diagnosis was cardiomegaly with a particularly enlarged left atrium. All previous cases of pulmonary arteriovenous malformations diagnosed prenatally have been reported as an isolated anomaly or in association with simple heart defects. We here describe the first case of a pulmonary arteriovenous malformation with a complex heart defect that was diagnosed prenatally at 21.0 weeks of gestation and confirmed by postmortem autopsy.

Multiple Detector Computed Tomography Evaluation of Congenital Pulmonary Venolobar Syndrome: Scimitar Syndrome with Pulmonary Arterio-Venous Fistula.

The term dysmorphic lung has been introduced to describe any complex congenital malformation that involves both abnormal pulmonary vascular morphology and disordered growth of the entire lung. The major group within this definition of the dysmorphic lung is the scimitar syndrome. Scimitar syndrome is a rare anomaly consisting of partial anomalous pulmonary venous return into the supra or infradiaphragmatic portion of the inferior vena cava, right lung hypoplasia, dextroposition of the heart, and anomalous systemic arterial supply from the aorta or one of its branches to the right lung. It can be associated with congenital cardiovascular defects namely dextrocardia, coarctation of the aorta, Tetralogy of Fallot, patent ductus arteriosus, atrial or ventricular septal defect, and right pulmonary artery hypoplasia. Associated pulmonary anomalies are lung hypoplasia, sequestration, and tracheobronchial anomalies. Thus, it can manifest with heart failure and recurrent pneumonia. Other reported associated anomalies include bronchogenic cysts, horseshoe lung, accessory diaphragm, and hernias. We report an 8-year-old boy with complaint of chest pain, who was diagnosed as having scimitar syndrome with rare association of pulmonary arteriovenous fistula within the involved lung and role of newer faster multiple detector computed tomography scanner in its evaluation.