Echocardiographic evidence of aortopulmonary collaterals in premature infants after closure of ductus arteriosus

Aortopulmonary collaterals occur in a variety of congenital heart diseases, in chronic pulmonary infection and abscesses, in association with lung tumors, and after multiple pulmonary emboli. In patients with congenital cyanotic heart disease aortopulmonary collaterals mainly occur in conditions with reduced pulmonary blood flow. We investigated 12 preterm low-birth-weight infants, gestational age 29.3+/-3.3 weeks, with respiratory failure who suffered from moderate to severe chronic lung disease after a period of mechanical ventilation. All patients developed aortopulmonary collaterals after closure of a patent ductus arteriosus. Aortopulmonary collaterals could be displayed clearly by color Doppler echocardiography and originated mainly from the descending aorta or the aortic arch. Hypoxic and hypercapnic episodes favored the development of aortopulmonary collaterals, which disappeared after pulmonary hemodynamics and respiratory function had improved. In only one patient coiling of a large col lateral vessel had to be performed. Systemic-to-pulmonary collateral vessels potentially aggravate chronic lung disease by increasing collateral pulmonary blood flow and reducing lung compliance. We conclude that aortopulmonary collaterals occur in bronchopulmonary dysplasia and can cause major problems in ventilated premature infants. Echocardiographic evaluation is important to prevent aggravation of chronic lung disease of infants at risk.     

Echocardiographic findings before and after interventional occlusion of a persistent ductus arteriosus Botalli using the Rashkind Occluder System

AIM: The aim of this study was to investigate whether before releasing the Rashkind occluder system for occlusion of persistently patent ductus arteriosi Botalli from the delivery catheter its position can be adequately demonstrated sonographically to avoid angiography. METHOD: From March to August 1993 occlusion of a persistently patent ductus arteriosus by means of the Rashkind system was carried out in 10 patients. A standard technique using transthoracic echocardiography was used. RESULTS: Echocardiography allowed to demonstrate and locate the occluder system in all cases. CONCLUSION: Echocardiography is a reliable means for locating the Rashkind occluder system avoiding angiography.     

Patent ductus arteriosus in neonates

Patency of the ductus arteriosus is one of the more common problems of the neonate. Although the ductus arteriosus usually closes within the first days of life, persistent patency can complicate the clinical status of a newborn. The ductus arteriosus also may play a role in the pathophysiology of persistent pulmonary hypertension of the newborn and in some forms of congenital heart disease. Diagnosis of patent ductus arteriosus can be suspected clinically but should be verified by echocardiography before treatment. Accurate diagnosis, early intervention and proper treatment are necessary to decrease the immediate risks and minimize the potential for long-term complications.     

Mechanisms of oxygen-induced contraction of ductus arteriosus isolated from the fetal rabbit

The present study was designed to investigate the effect of O2 on intracellular Ca concentration ([Ca]i) in the ductus arteriosus and the mechanisms for O2-induced ductal contraction. The force of isometric contraction of the ring of the ductus arteriosus isolated from fetal rabbits at 30 days of gestation (term, 31 days) was measured. The ductus arteriosus was loaded with fura 2, a calcium-sensitive dye, and [Ca]i was determined from the ratio of fluorescence intensity at 340 and 380 nm excitation wavelengths. The ductus arteriosus was initially superfused with hypoxic control solutions and contraction was induced by application of oxygenated solutions. The O2-induced contraction of the ductus arteriosus was associated with increases in [Ca]i and was eliminated in the absence of extracellular calcium. An increase in [K]o from 5 to 50 mM, which causes membrane depolarization, induced ductal contraction. The calcium channel blockers verapamil, diltiazem, and nickel caused a similar inhibition of O2-induced contraction as well as KCl-induced contraction. The role of intracellular calcium stores in O2-induced ductal contraction was examined using ryanodine, an inhibitor of calcium uptake and release from the sarcoplasmic reticulum. The inhibition of O2-induced contraction by ryanodine was minimal. Infusion of glibenclamide, an inhibitor for opening the ATP-sensitive potassium channel, caused contraction of the ductus arteriosus in the hypoxic solution. Cromakalim, an opener of ATP-sensitive potassium channels, completely relaxed the contraction induced by O2. These data suggest that O2 increases [Ca]i and causes contraction in the ductus arteriosus. Application of O2 may change from anaerobic to aerobic metabolism and depolarize membrane potential by closing the ATP-sensitive potassium channel, which in turn increases calcium influx via the voltage-dependent calcium channel. Mechanisms other than the ATP-sensitive potassium channel may also be involved in the O2-induced contraction and remain to be studied.     

Truncus arteriosus with patent ductus arteriosus and normal aortic arch

In hearts with a common arterial trunk (truncus arteriosus), there is almost always an inverse development of the aortic arch and the ductus arteriosus. Truncus with a normal aortic arch and a patent ductus is a rare echocardiographic and surgical finding. In this report, we describe 2 neonates in whom truncus arteriosus with a normal aortic arch and a medium or large patent ductus was diagnosed by preoperative echocardiography (without catheterization) and confirmed intraoperatively.     

Aneurysm of the nonpatent ductus arteriosus in the newborn

Aneurysm of the nonpatent ductus arteriosus in the newborn is a rare, but potentially fatal condition. Of reported ductal aneurysm up to 1969, diagnosis was made at autopsy only. We report here to our knowledge for the first time on a two week old infant with correct preoperative angiographic diagnosis followed by a successful surgical cure.     

Patent ductus arteriosus occlusion using detachable coils

Occlusion of patent ductus arteriosus was performed using detachable coils in 193 cases, with 181 successful implants and a low embolization rate. This technique is safe and effective for occlusion of ductuses of various sizes, and is low cost.     

Doppler ultrasonic flow detection as an adjunct in the diagnosis of patent ductus arteriosus in premature infants

Since ligation of a patent ductus arteriosus in the neonate with idiopathic respiratory distress syndrome seems to improve the clinical condition of the infant, we have attempted to identify those neonates earlier with the noninvasive Doppler ultrasonic technique, recording brachial arterial flow signals. Sixteen patients were studied. In the 5 with reversed brachial flow who were operated upon, ligation of a PDA resulted in improvement and postoperative correction of brachial flow reversal as evidenced by the Doppler ultrasonic technique.     

Patent ductus arteriosus and pulmonary artery endarteritis]

The authors present losartan, an angiotensin II receptor inhibitor with respect to its clinical interest and its practical and economical aspects.     

Effectiveness of five-loop coils to occlude patent ductus arteriosus

Coil occlusion of patent ductus arteriosus with 5-loop coils was undertaken in 10 patients without coil embolizations, and with 90% immediate occlusion and 100% occlusion at follow-up. We conclude that 5-loop coil occlusion of patent ductus arteriosus is safe and effective.