Unusual distal right pulmonary artery origin from right ductus arteriosus with uncommon left-sided aortic arch / Inusual origen de la parte distal de la arteria pulmonar derecha en un ductus arterioso derecho en arco aórtico izquierdo no común

Abstract A bilateral persistent ductus arteriosus with right proximal pulmonary artery agenesis is a very unusual anatomic variant. These malformations are assumed to occur during the transformation of the sixth aortic arch with the pulmonary trunk in the development of the aorta and its branches. A 2-months preterm baby was referred by severe bronchopulmonary dysplasia. Transthoracic echocardiography showed a large pulmonary trunk and left pulmonary artery. No right proximal pulmonary artery was found. Cardiac computed tomography study showed bilateral ductus arteriosus. The right proximal pulmonary artery was originated from an arterial structure coming off the right subclavian artery, a right ductus arteriosus. The aortic arch was left-sided, with a peculiar variant at the exit of the supraaortic vessels. Right subclavian artery emerged as the first supraaortic vessel, followed by a common trunk, giving rise to both carotids and the left subclavian artery as the last vessel. Right lung was hypoplastic with interstitial disease. The calibre of the right proximal pulmonary artery was inadequate to perform a corrective surgery. LDA closure was performed, keeping a prostaglandin infusion to maintain right ductus arteriosus patency until right proximal pulmonary artery size will be big enough to perform a successful surgical reconstruction. Unfortunately, right ductus arteriosus became narrow at its origin and she developed severe pulmonary hypertension and the patient died.

Resumen El ductus arterioso bilateral con agenesia proximal de la arteria pulmonar derecha es una variante anatómica rara producida por alteraciones de la transformación del sexto arco aórtico en las arterias pulmonares, la aorta y sus vasos, durante el desarrollo embrionario. Se presenta el caso de un bebé prematuro de dos meses, que fue derivado a nuestro hospital por displasia broncopulmonar severa. El ecocardiograma transtorácico no identificó el origen de la arteria pulmonar derecha. El estudio por tomografía computarizada cardiaca mostró ductus arterioso bilateral e identificó el origen distal de la arteria pulmonar derecha en una rama de la arteria subclavia derecha, identificada como ductus arterioso derecho. El pulmón derecho era hipoplástico y presentaba alteraciones intersticiales. A su vez, el patrón de los vasos supraaórticos era anómalo. El primer vaso correspondió a la arteria subclavia derecha, seguido por tronco común de ambas carótidas y por último la arteria subclavia izquierda. El calibre de la arteria pulmonar derecha fue inadecuado para realizar una cirugía correctiva, por lo cual se decidió cerrar el ductus arterioso izquierdo y mantener infusión de prostaglandina hasta que la arteria pulmonar derecha tuviera un calibre adecuado para la cirugía. Infortunadamente, el ductus arterioso derecho se cerró en su origen, desarrollándose hipertensión pulmonar severa y la paciente falleció.

Staged Repair of Unilateral Absence of the Right Proximal Pulmonary Artery Using Autologous Azygos Vein Graft Interposition / 日本心臓血管外科学会雑誌

The isolated unilateral absence of a proximal pulmonary artery is a rare congenital lesion that presents various symptoms. Although some reports have shown one-stage reconstruction of the pulmonary circulation in infants, the two-stage approach is required in the situation of pulmonary arterial hypoplasia. In these cases, the usual approach is systemic pulmonary shunting for the first operation, to obtain growth of the pulmonary vascular bed, and then connecting bilateral pulmonary arteries for the second operation. Moreover, in the majority of patients without a right proximal pulmonary artery, some material is required for reconstructive surgery that corresponds to the patient's growth. A girl aged 2 years and 10 months with absent right proximal pulmonary artery, underwent modified Blalock-Taussig shunting with a free autograft of the azygos vein. The shunt was banded to prevent excessive pulmonary blood flow. Reconstructive surgery was performed 10 months after the first operation. At the second operation, growth of the right distal pulmonary artery and azygos autograft was satisfactory. Therefore, we used this autograft as an interposed graft of the right and main pulmonary arteries. Her postoperative course was uneventful. We advocate the usefulness of the azygos vein for graft material possessing the possibility of growth. This autograft is useful for pulmonary arterial reconstruction, such as the present case, and also may be useful for a systemic-pulmonary shunt, while growth is anticipated for more complex heart diseases.