Doppler echocardiographic flow characteristics of isolated patent ductus arteriosus: better delineation by Doppler color flow mapping

Eighteen infants and children with isolated ductus arteriosus and various hemodynamic states were examined with the Doppler color flow mapping technique to study the flow patterns of the patent ductus and its adjacent structures. Direct visualization of the ductus was achieved in all patients. All ductal flow was shunting left to right from the descending aorta to the pulmonary artery even in the presence of significant elevation of pulmonary artery pressure. However, transient bidirectional shunting was observed in two patients on serial studies. Disturbed systolic and diastolic flows were demonstrated within the ductus in each case. The blood flows in the main pulmonary artery consisted of three distinguishable areas: 1) a characteristic high velocity turbulent retrograde ductal jet throughout the entire cardiac cycle, located in the anterolateral aspect of the main pulmonary artery; 2) nonspecific low velocity retrograde late systolic and early diastolic flow, located in the posteromedial aspect of the main pulmonary artery; and 3) low velocity forward systolic and diastolic flow, occupying the remaining area of the pulmonary artery. The blood flows in the descending aorta near the ductal orifice consisted of disturbed systolic and diastolic flows in a reversed direction. By providing detailed real time blood flow information with simultaneous imaging of the ductus, Doppler color flow mapping greatly facilitates the detection of a small ductal shunt. This technique also allows detection of a bidirectional or right to left ductal shunt.     

Arterial duct closure with detachable coils: application in the small child

Transcatheter closure of patent ductus arteriosus using controlled-release coils was performed in 16 patients weighing < 10 kg. No embolization occurred. Procedure-related complications occurred in 3 patients (18.8%): massive femoral hemorrhage in 1 and femoral artery thrombosis in 2. The ductus recanalized in 1 of them because of mechanical hemolysis caused by streptokinase treatment. This was the only patient who underwent another occlusion procedure. Complete occlusion was achieved in 7 patients (43.8%) immediately, in 13 (81.2%) the following day, and in all 15 patients who had completed the 6-month follow-up. During follow-up, flow velocities between the left and the main pulmonary arteries and between the descending and the ascending aortae did not differ significantly. Flow velocity was > 2 m x sec(-1) in 3 patients in the left pulmonary artery and in 1 in the descending aorta. Protrusion of the coil was seen in 3 of these patients. Flow velocity was also high in the main pulmonary artery in the 4th patient. In conclusion, coil occlusion of ductus arteriosus is feasible in the small child, but no more than half a loop of the coil should be left at the pulmonary site. High flow velocity does not always mean obstruction.     

Does ductal occlusion with the gianturco coil cause left pulmonary artery and/or descending aorta obstruction?

Thirty-two patients (median age 4.5 years) underwent transcatheter Gianturco coil occlusion of a patent ductus arteriosus. Transthoracic echocardiography was performed the day after coil placement and at intermediate follow-up (median 8.6 months). Echocardiographic results were compared with angiographic and hemodynamic data obtained during catheterization. Two-dimensional (2D) echocardiography performed the day after ductal occlusion displayed evidence of coil protrusion into the left pulmonary artery in 28 of 31 patients (90%) and into the descending aorta in 17 of 29 (59%). However, pulsed Doppler analysis demonstrated normal left pulmonary arterial flow velocities in 28 of 29 patients (97%) and normal descending aortic flow velocities in 26 of 27 (96%). Pulse Doppler results were corroborated by angiographic and hemodynamic catheterization data, which showed no evidence of adjacent vessel obstruction. Peak Doppler velocities among patients with and without 2D echocardiographic left pulmonary artery or descending aorta coil impingement did not differ significantly. The discrepancy between 2D and pulse Doppler findings did not change significantly at intermediate follow-up. Thus, transcatheter occlusion of the patent ductus arteriosus with properly implanted Gianturco coils does not cause significant obstruction to flow in the left pulmonary artery or descending aorta despite frequently misleading 2D echocardiographic images of coil impingement on these vessels.     

Echocardiographic and Doppler evaluation of the aortic arch and brachiocephalic vessels in cerebral and systemic arteriovenous fistulas

Congenital arteriovenous fistulas presenting in the newborn period pose difficult diagnostic problems and simulate structural heart disease. Angiocardiography, when performed, demonstrates enlarged brachiocephalic vessels and rapid cerebral venous return. The value of echocardiographic imaging and measurement of the aortic arch and brachiocephalic vessels, and evaluation of the Doppler flow profile in these vessels as a means of making a rapid diagnosis of cerebral or thoracic arteriovenous fistula, was therefore assessed in 10 infants with these diagnoses seen over a 4 year period (1983 to 1987). Twenty-nine infants (median age 6 weeks) undergoing two-dimensional echocardiography but with no significant lesions were prospectively selected as controls. Nine of the 10 patients had congestive heart failure at presentation (mean age 2 days). A cranial bruit was heard in three and arteriovenous fistula was suspected in five patients. Aortic arch segments and brachiocephalic vessel dimensions expressed as ratios of the abdominal aorta showed significantly larger values in patients for the ascending aorta (p = 0.01), innominate artery (p less than 0.001), right and left subclavian arteries (p less than 0.001) and left common carotid artery (p less than 0.05). The thoracic descending aorta was, however, significantly smaller in patients (p less than 0.002). Retrograde diastolic Doppler flow in the descending aorta proximal to the ductus arteriosus and anterograde diastolic flow with a mean spectral flow-time integral 27% of systolic were present in patients only, whereas Doppler diastolic flow in brachiocephalic vessels, present in 5 of 29 control infants, was less than 15% of systolic flow and not accompanied by dilation of these vessels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection and quantitation of constriction of the fetal ductus arteriosus by Doppler echocardiography

Pulmonary hypertension may occur in the fetus in the presence of constriction of the ductus arteriosus. The feasibility of detection and quantitation of fetal ductal constriction by Doppler echocardiography was assessed in an animal preparation in which ductal constriction was created in the fetal lamb with a variable ligature causing varying degrees of fetal pulmonary hypertension (fetal pulmonary arterial systolic pressure 57 to 97 mm Hg and ductal gradient 9 to 42 mm Hg). Comparison of blinded, continuous-wave peak Doppler velocity (V) measurements of the ductal gradient with the modified Bernoulli assumption (gradient = 4V2) compared well with direct catheter measurements of instantaneous peak systolic gradient (r = .99, catheter = 0.95 X Doppler + 0.6), peak-to-peak gradient (r = .97), and mid-diastolic gradient (r = .85). Ductal constriction was characterized by an increase in the peak systolic and diastolic velocities. The normal human fetal ductus arteriosus blood flow velocity pattern was assessed by pulsed Doppler techniques in 25 normal human fetuses after 20 weeks gestation. The peak systolic flow velocity in the ductus arteriosus measured by image-directed pulsed Doppler echocardiography ranged from 50 to 141 cm/sec (mean 80 cm/sec) and increased with gestational age (r = .50). Diastolic velocity in the ductus arteriosus was consistently directed toward the descending aorta and ranged from 6 to 30 cm/sec. The ductal systolic velocities were the highest blood flow velocities in the fetal cardiovascular system. Application of these techniques to fetuses whose mothers were receiving indomethacin for treatment of premature labor at 30 to 31 weeks gestation confirmed this method to be sensitive for detection of fetal ductal constriction, which developed in three fetuses.(ABSTRACT TRUNCATED AT 250 WORDS)     

The value of Doppler color flow mapping in determining pulmonary blood supply in infants with pulmonary atresia with ventricular septal defect

Thirty-two neonates and infants with pulmonary atresia with ventricular septal defect were initially investigated with cross-sectional and spectral Doppler echocardiography and Doppler color flow mapping. All 32 had subsequent correlative angiography. This demonstrated that 24 infants had adequate-sized right and left pulmonary arteries (19 confluent, 5 nonconfluent). Of the five infants with nonconfluent pulmonary arteries, four had bilateral ductus arteriosus and one had a single left-sided ductus with anomalous origin of the right pulmonary artery from the ascending aorta. Nineteen infants had confluent pulmonary arteries, all of which were supplied by a single ductus. Eight infants had complete absence of or inadequate pulmonary arteries; all had multiple aortopulmonary collateral vessels arising from the descending aorta. The presence of adequate-sized right and left pulmonary arteries was correctly predicted in 21 of 24 infants by cross-sectional echocardiography alone and in all 24 by Doppler color flow mapping. Confluence of the right and left pulmonary arteries was predicted by cross-sectional imaging in 14 of the 19 infants in whom it occurred, and by Doppler color flow mapping in all 19 infants. The precise definition of the pulmonary blood supply was correctly predicted by Doppler color flow mapping in 16 of the 19 infants with confluent pulmonary arteries and a single ductus. However, in three infants in this group, Doppler color flow mapping made a false diagnosis of multiple aortopulmonary collateral vessels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Transcatheter coil embolization for patent ductus arteriosus in the elderly: Report of a case and review of the published work

Patent ductus arteriosus is the third most common congenital cardiovascular anomaly, however, it is rarely found in the elderly. We describe a case of patent ductus arteriosus in a 72-year-old woman in whom patent ductus arteriosus was successfully managed by transcatheter coil embolization. The patient had been diagnosed with a heart murmur for the first time 1 year earlier at the age of 71. She was asymptomatic but a continuous murmur was heard. Cardiac catheterization revealed migration of a catheter from the main pulmonary artery into the descending aorta through a patent ductus arteriosus and a significant step-up of oxygen saturation in the main pulmonary artery with a pulmonary-to-systemic flow ratio of 1.68. Aortograms demonstrated a communication between the aorta and the pulmonary artery through a patent ductus arteriosus with a minimal diameter of 3.7 mm. Transcatheter coil embolization of the patent ductus arteriosus was successfully carried out with two 0.052-inch-diameter Gianturco coils. Doppler echocardiographic study confirmed no residual shunt in the main pulmonary artery after the procedure. Non-surgical transcatheter occlusion using coil embolization appears to be an effective and minimally invasive technique for treatment of patent ductus arteriosus in the elderly.     

Doppler echocardiographic measurement of pulmonary artery pressure from ductal Doppler velocities in the newborn

The ductal flow velocities in 37 newborns (group 1: persistent pulmonary hypertension [n = 16], transient tachypnea [n = 3], other [n = 2]; group 2: respiratory distress syndrome [n = 16]) were prospectively evaluated by Doppler ultrasound for the purpose of deriving systolic pulmonary artery pressures. Maximal tricuspid regurgitant Doppler velocity in 21 of these patients was used to validate the pulmonary artery pressures derived from ductal flow velocities. There was a significant linear correlation between tricuspid regurgitant Doppler velocity and pulmonary artery systolic pressure derived from ductal Doppler velocities in patients with unidirectional (pure left to right or pure right to left) ductal shunting (p less than 0.001, r = 0.95, SEE 8) and in those with bidirectional shunting (p less than 0.001, r = 0.95, SEE 4.5). Systolic pulmonary artery pressure in group 1 (67 +/- 13 mm Hg) was significantly higher than that in group 2 (39 +/- 10 mm Hg) (p less than 0.001). In those with bidirectional shunting, duration of right to left shunting less than 60% of systole was found when pulmonary artery pressure was systemic or less, whereas duration greater than or equal to 60% was associated with suprasystemic pulmonary artery pressures. Serial changes in pulmonary artery systolic pressure, reflected by changes in ductal Doppler velocities, correlated with clinical status in persistent pulmonary hypertension of the newborn. Persistently suprasystemic pulmonary artery pressure was associated with death in five group 1 patients. It is concluded that ductal Doppler velocities can be reliably utilized to monitor the course of pulmonary artery systolic pressures in newborns.     

Medium-term follow up of residual shunting and potential complications after transcatheter occlusion of the ductus arteriosus.

OBJECTIVES--To determine the causes and outcome of residual shunting after transcatheter occlusion of persistent ductus arteriosus with the Rashkind double umbrella occluder, and to determine the potential of the device to produce obstruction to flow in the aorta and left pulmonary artery. DESIGN--Angiographic examination of morphology of ductus followed by prospective clinical and ultrasound evaluation (including cross sectional imaging, colour flow mapping, and pulse wave Doppler) of all patients undergoing occlusion of persistent ductus arteriosus between October 1987 and July 1992. PATIENTS--140 patients with ages between 0.5 and 78 (median 3.8) years and weights between 6.8 and 74 (median 13.8) kg. INTERVENTIONS--Attempted implantation of the Rashkind double umbrella ductus occluder under angiographic control through a transvenous (n = 136) or transarterial (n = 4) approach. MAIN OUTCOME MEASURES--Successful occlusion of ductus; frequency, pattern, and prognosis of residual shunts; Doppler velocities in left pulmonary artery and aorta; volume loading of the left heart. RESULTS--Including reocclusions the overall rate of successful occlusion was 96%. A total of six devices embolised at the time of operation (4.3%) with no sequelae. There were no anatomical factors that predicted a poor outcome, but suboptimal positioning of the device led to a significantly higher incidence of residual shunts (p < 0.001). Colour flow mapping correctly identified shunts that were unlikely to close spontaneously (n = 9) and to date seven have undergone successful closure with a second device. Encroachment of device legs produced statistically (p < 0.001) but not clinically significant increases in left pulmonary artery Doppler velocities that diminished with time. CONCLUSIONS--Transcatheter occlusion provides a safe and effective means of closing a persistent ductus arteriosus. Doppler colour flow mapping is necessary for follow up and shows those ducts requiring reocclusion. The device did not produce significant disturbance to flow in the pulmonary arteries or aorta.     

Truncus arteriosus malformation: a spectrum including fourth and sixth aortic arch interruptions

Previous explanations of the pathogenesis of truncus arteriosus malformation have emphasized absence of conotruncal ridges, absence of pulmonary conus, or fusion of ventricular outflow streams. These concepts explain the persistence of the single semilunar valve and outflow vessel, but have not elucidated the significance of many associated anatomic lesions. We studied the 19 patients with truncus arteriosus malformation listed in the autopsy files of The Johns Hopkins Hospital whose hearts were available for review. The patients ranged in age from one day to 30 years, and included 12 males. All hearts showed a single semilunar valve with three or four cusps, and a high ventricular septal defect. In 13 patients, the aorta was larger in diameter than the pulmonary artery, and no remnant of the ductus arteriosus was present (interruption of the embryonic sixth arch). In one patient, the aorta was larger than the pulmonary artery, and a small, patent ductus arteriosus was present. In two patients, the pulmonary artery was larger than the aorta, and the aortic arch was interrupted. The remaining three cases could not be fully evaluated for the status of the ductus arteriosus and size of the great arteries. We tabulated the number of associated anatomic lesions which were unexplained by each of the three pathogenetic hypotheses. The fused outflow stream hypothesis, which explains truncus arteriosus malformation as the result of a maldirection of ventricular outflow streams so that the separation of two semilunar valves is prevented, was superior at the 0.05 level of significance. This concept explains the spectrum of great vessel patterns in which flow is dominant into either the sixth or fourth embryonic aortic arch, permitting early disappearance of unperfused segments of the aortic arches, and is commonly seen at autopsy as either an interrupted aorta or an absent ductus arteriosus.     

Fetal cardiac and peripheral arterial flow velocity waveforms in intrauterine growth retardation

Maximum flow velocity waveforms were studied at the cardiac level (ascending aorta, pulmonary artery, and ductus arteriosus) and at the peripheral level (fetal internal carotid artery, descending aorta, umbilical artery, and maternal uteroplacental artery) in 25 patients with intrauterine growth retardation and 25 normal control subjects matched for gestational age and maternal parity. Gestational age ranged from 27 to 35 weeks (median, 30 weeks). All flow velocity waveforms were obtained with a mechanical sector scanner combined with a pulsed and continuous Doppler system with a carrier frequency of 3.5 and 3.0 MHz. Normal pregnancy was characterized by low fetal and placental vascular resistances. The peak systolic velocity in the ascending aorta was significantly higher compared with the pulmonary artery. In patients with intrauterine growth retardation, reduced end-diastolic flow velocities were documented in fetal descending aorta, umbilical artery, and maternal uteroplacental artery, reflecting raised umbilical placental and uteroplacental vascular resistances. Raised end-diastolic flow velocities were observed at the cerebral level, reflecting reduced cerebral vascular resistance ("brain sparing" effect). Reduced peak systolic flow velocities documented at the cardiac level may be secondary to reduced volume flow, increased valve or vessel size, or raised afterload. The noninvasive nature of this study did not allow differentiation between these variables.     

Real-time Doppler color flow mapping for detection of patent ductus arteriosus

In this study, ultrasound Doppler color flow mapping systems were utilized to examine flow in the pulmonary artery in 31 premature and term infants (aged 4 hours to 9 months) with patent ductus arteriosus accompanying respiratory distress syndrome, as an isolated lesion, or with patent ductus in association with other cyanotic or acyanotic congenital heart disorders. The flow mapping patterns were compared with those of a control population of 15 infants who did not have patent ductus arteriosus. In unconstricted ductus arteriosus, the flow from the aorta into the pulmonary artery was detected in late systole and early diastole and was distributed along the superior leftward lateral wall of the main pulmonary artery from the origin of the left pulmonary artery back in a proximal direction toward the pulmonary valve. In constricted patent ductus arteriosus, or especially in a ductus in association with cyanotic heart disease, the position of the ductal shunt in the pulmonary artery was more variable, often directed centrally or medially. Waveform spectral Doppler sampling could be performed in specific positions guided by the Doppler flow map to verify the phasic characteristics of the ductal shunt on spectral and audio outputs. Shunts through a very small patent ductus arteriosus were routinely detected in this group of infants, and right to left ductal shunts could also be verified by the Doppler flow mapping technique. This study suggests substantial promise for real-time two-dimensional Doppler echocardiographic flow mapping for evaluation of patent ductus arteriosus in infants.     

New serial contrast technique for assessment of left to right shunting patent ductus arteriosus in the neonate

A new serial echocardiographic contrast technique for detection of patent ductus arteriosus has been developed and validated by clinical course (33 infants), surgical observations (13 infants) and autopsy observations (4 infants). A left to right shunting patent ductus arteriosus was demonstrated in 30 of 33 prospectively studied premature infants (mean weight 1,371 g) using this new contrast method. The demonstration of left to right ductal shunting was accomplished by hand injection of a nonviscous material (saline solution, 5 percent dextrose in water or the patient's own blood) through an umbilical arterial catheter placed with its tip located above the diaphragm during recording of a suprasternal notch echocardiogram. In positive studies, both the transverse aortic arch and right pulmonary artery were opacified. If no left to right shunt existed, only the transverse aortic arch was opacified.This serial study helped elucidate the natural history of patent ductus arteriosus. Twenty-four of the 30 patients with a positive study initially had a left to right shunting patent ductus arteriosus without an audible murmur. Three of these patients with silent patent ductus arteriosus later had congestive heart failure and two required operative ligation of the patent ductus. The high rate of detection of silent patent ductus arteriosus and its bedside confirmation when suspected are important in the serial management of critically ill newborns with this condition. The test is safe and sensitive and it is useful for early demonstration of silent patent ductus arteriosus, for clarifying the origin of murmurs and for confirming spontaneous, operative or pharmacologie closure of a patent ductus arteriosus.     

经导管堵闭婴幼儿大型动脉导管未闭(≥4mm)的短中期随访

目的分析经导管封堵婴幼儿大型动脉导管未闭(patent ductus arteriosus,PDA)(≥4 mm)的短中期随访的结果。方法回顾性分析50例大型PDA患儿的疗效、并发症及中期随访结果 ,评价其中期疗效、安全性及影响疗效的因素。结果成功植入封堵器49例(98%),其中46例(92%)应用PDA封堵器,2例(4%)应用肌部室间隔缺损封堵器,1例(2%)应用膜周对称型室间隔缺损封堵器。术后3 d内复查超声心动图:4例(8%)有残余分流;封堵后左心室舒张末内径、左心房内径、左心室射血分数、肺动脉收缩压、三尖瓣反流(tricuspidregurgitation,TR)及二尖瓣反流(mitral regurgitation,MR)均较术前缩小或减轻,差异有统计学意义(P<0.05);封堵后主动脉收缩压及主动脉瓣反流(aortic regurgitation,AR)较术前增加或加重,差异有统计学意义(P<0.01)。出院后完成随访41例,随访率81.6%,中位随访时间6个月(1～57个月)。残余分流率在术后3 d、1个月、6个月分别为8%、4%、2%。术后1～6个月内左心室射血分数较术后3 d有明显改善,差异有统计学意义(P=0.000);术后1年内随访:MR较术前降低,差异有统计学意义(P=0.000);AR及TR与术前比较,差异无统计学意义(P>0.05);术后1年内11例患儿出现左肺动脉血流速度加快(1.5～2.1 m/s),其中9例随访1年以上左肺动脉血流1.5～2.0 m/s,4例随访3～5年左肺动脉血流速度1.5～2 m/s,但左肺动脉至主肺动脉压差均≤20 mm Hg(1 mm Hg=0.133 kPa)。无降主动脉狭窄。结论经导管用封堵器治疗婴幼儿大型PDA(≥4 mm)的短中期疗效确切,安全性好,但对左肺血流速度增快患者需长期随访。     

Descending aortography with balloon inflation. A technique for evaluating the size of persistent ductus arteriosus in infants with large proximal left to right shunts

Six infants underwent angiography of the aortic root and the descending aorta with balloon inflation during diagnostic cardiac catheterisation and angiography. In these infants with large proximal left to right shunts, descending aortography with balloon inflation resulted in better opacification of the persistent ductus arteriosus than aortic root angiography, thereby enabling accurate measurement of the persistent ductus arteriosus. Similar systemic and pulmonary vascular impedances had been speculated as the cause of poor or non-opacification of the ductus after ascending aortography. Balloon inflation may have altered the aortic impedance with resulting opacification of the ductus. Descending aortic angiography with balloon inflation is also useful in opacifying the isolated ductus and in demonstrating aortopulmonary collaterals in patients with pulmonary atresia.     

Hypoplastic left heart syndrome: is echocardiography accurate enough to guide surgical palliation?

Two-dimensional echocardiography can diagnose hypoplastic left heart syndrome. However, with the advent of the possibility of palliative open heart surgery, complete anatomic diagnosis is necessary. The anatomic findings of 15 neonates with hypoplastic left heart syndrome (age 1 to 10 days, mean 4.1) who had two-dimensional Doppler echocardiographic studies were compared with the results obtained by angiography (6 cases), surgery (11 cases) and autopsy (8 cases). Complete two-dimensional echocardiographic examination of the aortic arch, pulmonary and systemic venous return, atrial septum, ductus arteriosus and proximal coronary arteries was possible in all 15 neonates and correctly diagnosed hypoplastic left heart syndrome in each. Anatomic two-dimensional echocardiographic assessment was accurate in 13 (86%) of the 15 neonates and there were no false positive results. Undiagnosed associated abnormalities were hypoplasia of a left pulmonary artery in one patient and left superior vena cava in another. Accurate quantitation of the size of the tricuspid valve anulus, ascending aorta, pulmonary anulus and right and left pulmonary arteries was possible. Doppler examination was performed in seven patients and confirmed retrograde aortic arch flow and right to left systolic shunting in the patent ductus arteriosus. In selected neonates, surgical palliation can be attempted without angiography.     

A pulsed Doppler echocardiographic study of the postnatal changes in pulmonary artery and ascending aortic flow in normal term newborn infants

Postnatal circulatory adaptations were studied with Doppler echocardiographic measures of flow velocity in the main pulmonary artery (PA) and ascending aorta (Ao) in 45 normal full-term neonates at 5 hours and at 27 hours after birth. PA flow velocity integral (FVI) was measured as the area under the systolic flow velocity curve and reflected total systemic flow in the presence of a left-to-right shunt through the ductus arteriosus. This index increased from 5 and 27 hours age, while Ao FVI, reflecting total pulmonary flow, remained unchanged. Evidence of a left-to-right ductal shunt demonstrated as diastolic retrograde flow in the main PA was detected in 42 neonates at 5 hours and in only four subjects after 27 hours of age, indicating a patent ductus arteriosus at 5 hours of age and its subsequent closure. In the PA, acceleration time (AT) increased while pre-ejection period to ejection time ratio (PEP/ET) decreased from 5 to 27 hours of age, reflecting the physiologic fall in PA pressure. In the Ao, FVI, AT, and PEP/ET remained unchanged, suggesting little change in left ventricular function.     

Transcatheter management of patent ductus arteriosus in sick ventilated small infants

BACKGROUND: Large patent ductus arteriosus can present in infancy with congestive cardiac failure and superadded pulmonary infection can necessitate mechanical ventilation. Surgical intervention is traditionally indicated for this subset of patients. We present our experience of transcatheter coil closure of the patent ductus arteriosus in such infants. METHODS AND RESULTS: Five infants weighing between 960 gm and 4.1 kg, aged between 17 days and 3 1/2 months were mechanically ventilated because of congestive cardiac failure with pneumonia. Echocardiography showed patient ductus arteriosus with a size of 1.8 to 4.2 mm and adequate ampulla. Bioptome-assisted coil delivery was done and successful patient ductus arteriosus closure was achieved in all. There were two instances of embolization of coils with successful retrieval and redeployment. All infants could be weaned off mechanical ventilation over the next 24-72 hours. A pre-term infant developed a Doppler gradient of 25 mmHg in the descending aorta that decreased to 12 mmHg five months later. There was no significant obstruction to pulmonary artery flow in any child. At three months follow-up, all the five infants were asymptomatic with no residual flow across the patient ductus arteriosus. CONCLUSIONS: Transcatheter coil closure of moderate to large patent ductus arteriosus is possible in sick ventilated infants weighing below 5 kg. It may be a better alternative to surgery in selected cases in view of minimal morbidity.     

Stenting the patent arterial duct to increase pulmonary blood flow

BACKGROUND: Use of surgically created aoropulmonary shunt is well-established for improving pulmonary blood flow in infants with critical reduction in pulmonary blood flow. Recently, stenting the patent ductus arteriosus has emerged as an alternative in selected infants with congenital heart disease and reduced pulmonary blood flow. METHODS AND RESULTS: We reviewed records of consecutive infants undergoing stenting of patent ductus arteriosus between August 2003 and October 2005 at our institution. Two of 12 patients underwent patent ductus arteriosus stenting to facilitate preparation of left ventricle for transposition with intact septum. We report the case selection, technique, immediate and short-term follow-up outcome in the remaining 10 patients [median age: 16 days (range 4-290 days): weight 2.7 kg (range 2-6 kg)] with reduced pulmonary blood flow who underwent stenting of patent ductus arteriosus as an alternative to conventional surgical aortopulmonary shunts. Five of the 6 newborns were prostaglandin-dependent and 4 had previously undergone guidewire perforation of the pulmonary valve (n=2) or balloon dilation (n=2). Successful stent implantation was accomplished in all with no major patient-related complication (median fluoroscopy time: 18.6 min; range: 7.7-72 min). The intensive care unit and hospital stays were prolonged in 3 patients because of sepsis (n=2) and pulmonary over-circulation with sepsis (n=1). On follow-up (median 5.5 months; range 1-19 months) all implanted stents were patent. One patient underwent re-dilation of the implanted stent for declining saturations. CONCLUSIONS: The immediate and short-term follow-up results of stenting of the patent arterial duct, as an alternative to the surgical aortopulmonary shunt in carefully selected newborns and infants is encouraging.     

Pulsed doppler echocardiographic evaluation of the cyanotic newborn: Identification of the pulmonary artery in transposition of the great arteries

During M mode echocardiographic evaluation of cyanotic newborn infants, one may find two ventricles and two great vessels, but not have proof of their identity. Identification of the great vessels is important in evaluation of possible transposition of the great arteries. In a series of 68 cyanotic neonates pulsed Doppler echocardtography was applied to test the hypotheses that (1) a patent ductus arterlosus in present in most cyanotic neonates, (2) the great vessel that receives diastolic ductal flow is the pulmonary artery, and (3) specific noninvasive identification of pulmonary artery will allow diagnosis or exclusion of transposition of the great arteries. On M mode examination, the relations of the great vessels were normal in 43 infants; in all, pulsed Doppler echocardiography detected a patent ductus arteriosus flowing into a normally positioned pulmonary artery. The cyanosis in these 43 patients was later proved to be of pulmonary origin. In eight infants, the relation of the great vessels suggested transposition, and in all eight, Doppler echocardiography detected a patent ductus flowing into the posterior great vessel, proved at angiocardiography to be the transposed pulmonary artery. In 17 patients, the relation of the great vessels was front to back, neither “normal” nor suggestive of classic d transposition. A patent ductus arterlosus, detected with pulsed Doppler echocardiography in all 17, flowed into the anterior great vessel in the 14 normal infants, and flowed into the transposed pulmonary artery in the 3 with proved transposition. It is concluded that ductal patency is prevalent in cyanotic neonates, and that pulsed Doppler echocardiographic detection of ductal flow can define the pulmonary artery; such definition is most helpful in resolving the question of transposition in infants with a relation of the great vessels that is neither normal nor suggestive of transposition.