• The action of sympathetic and parasynipathetic nerves on the pulmonary vessels is well known. However, until recently, it was thought that the circulation of blood in the lungs was achieved passively. Anatomical and pathological studies have shown that in cases of pulmonary hypertension there is a marked hypertrophy of the muscular coat of the pulmonary artery, which suggests an active vasoco...

OBJECTIVE To assess the efficacy of arterial duct angioplasty in maintaining adequate ductal patency in neonates with critical pulmonary valve stenosis. PATIENTS Two neonates presenting with cyanosis due to critical pulmonary valve stenosis with severe right ventricular hypoplasia underwent percutaneous balloon dilatation of the pulmonary valve. Despite successful dilatation, both remained cy...

Fetal origin of HPV HPV originates in the fetus [3]. Vasomotor tone can be detected in the human fetal pulmonary circulation in the last trimester of pregnancy [4]. HPV contributes significantly to the high pulmonary vascular resistance (PVR) in the fetus (only 10–15% of right ventricular outflow goes to the lungs) [5], mainly because pulmonary artery and alveolar fluid oxygen tension (PO2) lev...

The structure of the pulmonary circulation throughout the lung has been analysed by morphometric techniques in 4 infants dying with ventricular septal defect and pulmonary hypertension. Failure of the intra-acinar pulmonary circulation to develop normally is shown by a reduction in arterial size and number, and an increase in muscularity is judged by the degree of medial hypertrophy and by exte...

Pulmonary arterial hypertension (PAH) is a syndrome that results from restricted blood flow through the pulmonary arterial circulation, which leads to a pathological increase in pulmonary vascular resistance (PVR) and ultimately to right heart failure. The prognosis of patients with PAH has improved with the recent development of new medications. The need for new noninvasive diagnostic tools is...

BACKGROUND Staged palliative surgery markedly shifts the balance of volume load on a single ventricle and pulmonary vascular bed. Blalock-Taussig shunt necessitates a single ventricle eject blood to both the systemic and pulmonary circulation. On the contrary, bidirectional cavopulmonary shunt release the single ventricle from pulmonary circulation. CASE PRESENTATION We report a case of tricu...