Patent Ductus Arteriosus
Patent ductus arteriosus is a communication between the aorta and pulmonary artery in the fetus, which at birth physiologically closes due to increased blood pressure and decrease oxygen prostaglandins. It normally closes in the first 10-15 hours of life, the patent ductus arteriosus being the result of not closing it.
Patent ductus arteriosus is more common in female infants and premature infants. Because of the patency of the arterial channel, blood passes from the aorta into the pulmonary artery, creating a right-left shunt (oxygenated blood from the left ventricle passes into deoxygenated blood which goes to the lungs). The consequences of patent ductus arteriosus, depends on the channel size and age of the child. This left-right shunt type may be asymptomatic if a small arterial channel or may determinate hypertension at the pulmonary vessels level even with reversing time (years) resulting in Eisenmenger syndrome.
Eisenmenger syndrome occurs when the shunt becomes right-left (deoxygenated blood mixes with oxygenated blood) with symptoms that begins at 20-40 years with hypoxia (decreased oxygenation of tissues), cyanosis (bluish purple discoloration of the skin), hippocratic fingers, fatigue, dyspnea, arrhythmias, chest pain, palpitations, right heart failure.
In patent ductus arteriosus symptoms differs depending on the child (age) and channel size. In a small arterial channel there are no specific symptoms and there are no changes. In a large arterial channel we can listen to a continuous breath in the left sternal edge upper portion and signs of heart failure can occur (the child does not grow, does not feed, rapid breathing and not breathing well when breastfed, has tachycardia – heart rate frequency above normal age). In patent ductus arteriosus in premature birth, signs of heart failure are more frequent and can be accompanied by serious complications such as respiratory distress, apnea or necrotic enterocolitis.
Diagnosis and Treatment
Diagnosis of patent ductus arteriosus is put on the clinical picture and paraclinical explorations (electrocardiogram, chest x-ray and 2D echocardiography and Doppler). This may be normal if a small arterial channel or can view the dilatation of the left atrial, of the left ventricle, aortic dilatation and emphasizing the pulmonary design (chest radiography), right ventricular hypertrophy (electrocardiogram) or direct visualization of blood flow are echocardiography.
For arterial channel treatment it can be used indomethacin (more efficient in preterm, inefficient in neonates at term), that in case of failure is followed by surgical intervention. If the ductus arteriosus is big, the surgical intervention is recommended to perform between six months and three years, even faster in case of heart failure after balancing it. Before and after surgical intervention for patent ductus arteriosus is recommended endocarditis bacterial prophylaxis.