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.     

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.     

Real-time bidimensional-color Doppler evaluation of patent ductus arteriosus

In order to assess the presence and severity of left-to-right shunt at ductal level, eleven patients with proven ductus arteriosus (PDA), ages 1 day to 16 years, were examined by real-time two-dimensional Doppler echocardiography. Eighteen subjects with no signs of cardiovascular disease were selected as normal controls. Normal pulmonary flow pattern was clearly visualized in the healthy subjects examined. The jet stream through the ductus was well imaged in the main pulmonary artery in patients with PDA and disappeared in two infants after pharmacologic manipulation with indomethacin. The colour-coded shunt area was related to the left-to-right shunt calculated at cardiac catheterization. Moreover, the combined use of colour-flow Doppler and continuous-wave Doppler yielded a reliable noninvasive assessment of pulmonary artery pressure.     

Patency of the ductus arteriosus in normal neonates: two-dimensional echocardiography versus Doppler assessment

Two-dimensional echocardiography using a high resolution, 7.5 ,Jsz transduce was compared with Doppler echocardiography for the assessment of patency of the ductus arteriosus in normal newborn infants. Twenty-eight neonates were studied between 1 and 10 hours (mean 5.5) after birth and both examinations were possible in 27 (96%). Doppler echocardiography under two-dimensional direction indicated ductal patency in all 27 neonates. Doppler sampling in the pulmonary end of the ductus rather than the main pulmonary artery was more sensitive for detecting patency. When two-dimensional echocardiography only was used to predict patency, there was 85% sensitivity. Two-dimensional echocardiography showed no evidence of ductus arteriosus narrowing ion four neonates studied shortly after birth. In 18, the pulmonary portion of the ductus arteriosus appeared narrowed and in 8 of these, the narrowing extended toward the mid-portion of the ductus. In five others, there was only mid-ductus arteriosus narrowing. It is concluded that high resolution two-dimensional echocardiography can be used to assess ductus arteriosus morphology, but is limited in predicting ductal patency near the time of normal physiologic closure. Combined two-dimensional and Doppler echocardiography is a highly sensitive technique for detection of ductal patency when sampling is performed in the pulmonary end of the ductus arteriosus.     

Aortic dissection and patent ductus arteriosus in three generations

Aortic dissection was found in a woman, her 2 sons, and 1 of her 3 daughters, and the 3 affected children and a granddaughter had patent ductus arteriosus. The pattern of inheritance of this unique syndrome probably is an autosomal dominant one.     

Pulsed Doppler and bidimensional echocardiography in patent ductus arteriosus

The classical form of patent ductus arteriosus (PDA) does not usually pose any difficulty in diagnosing. When the auscultatory signs are atypical, for example in the newborn or in cases with pulmonary hypertension, pulsed Doppler echocardiography may be a useful diagnostic aid. This study reports the results of pulsed Doppler examination in PDA. Twenty-four children with a suspected PDA underwent pulsed Doppler examination during 2D echocardiography. This population was divided into 2 groups; Group I: children who underwent catheterisation, and group II: in which catheterisation was not performed. The mean age in Group I was 7 years compared to 50 days in Group II, which mainly comprised newborn and premature babies. Direct visualisation of PDA by 2D echo was attempted in all cases. The search for a PDA by pulsed Doppler was made by positioning the sample volume at the bifurcation of the main pulmonary artery. PDA is associated with turbulent systolo-diastolic flow away from the transducer. Suprasternal and subcostal views were also used. In Group I (13 cases) PDA was directly visualised by 2D echo in 7 children (53 p. 100). By comparison, pulsed Doppler examination diagnosed all 13 cases of PDA; these results were confirmed at catheterisation or surgery. In Group II (11 cases) direct visualisation of PDA was successful in 6 cases (54 p. 100). Pulsed Doppler was non-specific, showing typical flow disturbances in 8 cases and systolic turbulence in 3 cases at the level of bifurcation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Doppler flow evaluation can anticipate abnormal left lung perfusion after transcatheter closure of patent ductus arteriosus.

AIMS: Coil protrusion into the left pulmonary artery (LPA) has been described after transcatheter closure of the patent ductus arteriosus (PDA). The possible impact of such a finding in lung perfusion has not been completely clarified. We evaluated Doppler flow velocities and lung perfusion in patients submitted to that procedure. METHODS: After transcatheter closure of PDA with coils, 70 patients (mean age 8.6+/-3.4 years) were followed for a period of 3.6+/-0.9 years (range 2.1-5.9) and compared to 22 controls. Peak flow velocities and coil protrusion were assessed by Doppler echocardiography. A Doppler velocity index (DVI) was calculated by the difference between the LPA and right pulmonary artery (RPA) peak flow velocities relative to the pulmonary trunk (PT) expressed in percentage, as follows: DVI=(LPA velocity - RPA velocity)/PT velocity x 100. Lung scintigraphy was performed using (99m)Tc-labelled macro-aggregated albumin. RESULTS: Device protrusion was observed in 94% of the patients, 10% of whom presented abnormal left lung perfusion. Peak LPA velocity and DVI were significantly greater in patients (p=0.001) and correlated negatively with left lung perfusion values (R(2)=0.21 and R(2)=0.65, respectively). A cut-off value of 50% for the DVI showed high sensitivity and specificity for reduced lung perfusion. CONCLUSION: Impaired left lung perfusion may appear following transcatheter closure of PDA with coils and the determination of DVI may anticipate such alteration.     

Aortic valve regurgitation following percutaneous closure of patent ductus arteriosus

Objectives : To determine the incidence and outcome of aortic valve regurgitation (AR) following the percutaneous closure of patent ductus arteriosus (PDA). Background : Aortic valve regurgitation is an overlooked consequence of percutaneous PDA closure. Methods : Between December 2000 and May 2009, 51 children underwent percutaneous closure of PDA using Amplatzer Duct Occluders. Their median age at the time of the procedure was 2.6 years (range: 0.6–18.0 years), and median weight was 14.0 kg (range: 7.6–75.0 kg). Follow‐up echocardiograms were performed a day after the procedure and at 1, 3, 12 months, and yearly thereafter. Results : A day after the procedure, AR was detected for the first time in 13 of 48 patients (27.0%). A group of patients with newly developed AR was significantly different from a group of patients with competent aortic valves with respect to their age, weight, and minimal PDA diameter indexed to the body weight. The follow‐up period ranged from 0.2 to 8.5 years (median 3.3 years) and at the latest follow‐up evaluation, AR persisted in a single patient (2.0%) 6 years after the procedure. Conclusions : The aortic valve regurgitation following percutaneous PDA closure is trivial to mild and transient. It develops in approximately a quarter of children after percutaneous closure of PDA with a minimal diameter ≥1.5 mm and is more likely to develop in infants and small children having significant left‐to‐right shunts. © 2010 Wiley‐Liss, Inc.     

Oral pharmacological treatment for patent ductus arteriosus in premature neonates with hemodynamic repercussions

Objective: To evaluate the efficacy of oral indomethacin, ibuprofen, and paracetamol in oral dosage form on patent ductus arteriosus(PDA) in premature neonates with significant clinical and hemodynamic repercussions(CHRs) and to determine the effect of these respective treatments on renal function.Methods: A retrospective study of cases of PDA in premature neonates in the Neonatal Intensive Care Unit was conducted. The treatments consisted of indomethacin[0.2 mg/(kg$d), 3-day cycle], ibuprofen [10 mg/(kg$d) followed by 5 mg/(kg$d), 3-day cycle], and paracetamol(15 mg/kg every 6 h, 5-day cycle). The drugs were administered as an oral solution. The following variables were considered: gestational age,newborn weight at birth, Apgar score, diuresis, serum creatinine and urea levels, and serum electrolyte levels(sodium and potassium).Results: Treatment with indomethacin presented efficacy of 87.5% in closure of the ductus with a mean outcome period of 3.5 d. In premature neonates with CHRs and contraindications for indomethacin, the initial treatment with either ibuprofen or paracetamol failed to close the ductus. However, when this treatment was followed by indomethacin, closure occurred in 66.7% of the neonates, with an outcome period of9.66 d. The initial treatment with one cycle of ibuprofen followed by one or two cycles of paracetamol failed to close the ductus.Conclusions: Oral indomethacin was effective for closure of the PDA in premature neonates with severe CHRs. Oral paracetamol or ibuprofen for PDA closure in premature neonates with severe CHRs and contraindications for indomethacin was ineffective.However, results in clinical improvements of neonates allowed the subsequent use of indomethacin and successful closure of the ductus. A significant reduction of diuresis occurred in neonates who were treated with indomethacin, either as a first-line treatment or after the failure of ibuprofen or paracetamol.     

二维超声心动图和彩色多普勒血流图诊断永存动脉干

目的 :分析永存动脉干 （ PTA）结构、血流动力学特征 ,并探讨切面的选择。方法 :应用彩色多普勒超声仪检测11例疑诊为 PTA患者的二维超声心动图 （ 2 DE）和彩色多普勒血流图 （ CDFI）。所有患者均使用剑突下、胸骨旁和胸骨上窝多部位和多切面检查心内结构。结果 :10例确诊为 PTA,1例诊断为肺动脉闭锁 ,心血管造影证实 11例均为 PTA。PTA 型 2例 , 型 1例 , 型 4例 , 型 4例。PTA起源左右心室之间 5例 ;主要起源于右心室 6例 ,骑跨率≥ 60 %。PTA双叶和四叶各 1例 ,三叶 9例。结论 :2 DE和 CDFI可用于识别 PTA病理解剖结构 ,血流动力学特征 ,且诊断符合率高 （ 91% ）     

Noninvasive Doppler echocardiographic evaluation of shunt flow dynamics of the ductus arteriosus

The pulsed Doppler technique was used to record the flow velocity patterns in the ductus arteriosus and the pulmonary artery in 26 patients with either isolated or complicated patent ductus arteriosus (PDA). In all patients, abnormal Doppler signals indicating left-to-right (L-R) or right-to-left shunt flow or both could be obtained at the site of the ductus arteriosus. These Doppler flow patterns determined within the ductus coincided with the direction of ductal flow seen on the contrast two-dimensional echocardiogram. No Doppler signals of shunt flow were demonstrated in any of 42 control subjects. The peak, mean, and diastolic velocities of the L-R shunt flow within the ductus were measured from the ductal flow velocity profiles. With the Doppler-derived measurements of the mean and diastolic velocities, patients with normal pulmonary arterial pressure and those with evidence of pulmonary hypertension could be correctly identified. In addition, the mean velocity of the diastolic antegrade flow portion obtained from the proximal left pulmonary artery, which was related to ductal L-R shunting, was measured in 16 patients with isolated PDA. This Doppler flow determinant showed a good linear correlation with the L-R shunt ratio determined by Fick's method (r = .88, p less than .01). Our technique permits the noninvasive evaluation of shunt flow dynamics in patients with PDA.     

口服消旋布洛芬治疗新生儿动脉导管未闭的疗效

目的：探讨口服布洛芬（INN）治疗新生儿动脉导管未闭（PDA）的疗效及安全性。方法：2011年2月至2013年12月在本院住院并经彩色超声心动图检查确诊有 PDA 的160例新生儿,按随机数字表法均分为高剂量组（第1d 给予布洛芬10mg/kg,第2d 和第3d 给予5mg/kg）,低剂量组（每天给予布洛芬5 mg/kg,连续3d）,每组各80例。观察两组经布洛芬治疗后 PDA 关闭情况并作对照分析。结果：本研究的160例 PDA 患儿,经 INN 治疗后96例（60％）闭合,高剂量组动脉导管关闭57例（71.3％）,显著高于低剂量组动脉导管关闭39例（48.8％）, P ＜0.01;两组患儿不良反应发生率无明显差异（P 均＞0.05）。结论：使用高剂量布洛芬治疗新生儿动脉导管未闭效果较好,不良反应少,可避免部分患儿以后手术的痛苦。