Pulmonary Branches Research Articles

Chimney Technique for Aortic Arch Repair in the Norwood Operation

Aortic arch repair is an important technical element in the Norwood operation for hypoplastic left heart syndrome that could adversely affect long-term results. Therefore, there are many controversies surrounding this procedure. We developed an alternative chimney technique for aortic arch repair without any supplemental materials. Both pulmonary branch orifices were resected en bloc from the posterior wall of the pulmonary trunk. The pulmonary defect was closed by longitudinal direct anastomosis. Consequently, the neo-aortic trunk was completed as a gradually converged, chimney-like shape. The effective length of the neo-aortic trunk elongated longitudinally, and the caliber of the trunk was reduced transversely. The elongated neo-aortic trunk could be anastomosed directly to the aortic arch without excessive tension. The neo-aortic trunk was joined to the aortic arch with a gentle shape. A hydrodynamically advantageous aortic configuration was completed, and a large subaortic arch space was provided. Chimney technique is an innovative procedure in the Norwood operation that requires no supplemental material.

Early and long-term results of biventricular repair of tetralogy of Fallot with or without pulmonary atresia

After complete repair, the long-term outcome difference between tetralogy of Fallot without pulmonary atresia (TOF) and tetralogy of Fallot with pulmonary atresia (TOF-PA) without MAPCAs is scarcely described. We performed a retrospective study on patients with a diagnostic of TOF and TOF-PA without MAPCAs who underwent complete repair between 1995 and 2016 in our center. We reviewed 960 patients, divided into two main anatomical groups: TOF ( n = 822, 85.7%), and patients with TOF-PA ( n = 138, 14.3%). Concerning surgical technique repair, three groups were distinguished: TOF without transannular patch ( n = 410, 42.7%), TOF/TOF-PA with transannular patch ( n = 494, 51.5%), and TOF-PA with RVOT tube ( n = 56, 5.8%). After complete repair, overall mortality was 11 (1.1%), five of them occurred before discharge (0.5%). Survival at 10 years after repair was 99.1% for TOF and 96.8% for TOF-PA ( P = 0.036). The median follow-up was 10.0 [95% CI: 6.3–14.1] years after repair. One hundred and sixty-three patients (17%) underwent reintervention (surgery or percutaneous interventions). Freedom from reintervention at 10 years after repair was 92.3%, 82.1%, and 48.7% for TOF without transannular patch, TOF/TOF-PA with transannular patch and TOF-PA with RVOT tube respectively ( P < 0.001 between each groups). In addition, reintervention rate was significantly different between TOF with transannular patch and TOF-PA with pulmonary trunk ( P < 0.001). In multivariate analysis, the absence of pulmonary trunk ( P = 0.013), pulmonary artery branches stenosis ( P = 0.001), prior palliative surgery ( P < 0.001), and reintervention before discharge ( P < 0.001) were reintervention risk factors. The initial anatomy of pulmonary trunk and branches strongly influences the risk of reintervention in TOF with or without PA. Avoid palliative surgery by directly performing a complete repair in the neonatal period would be a strategical option to improve the prognosis of these patients.

64-multidetector CT anatomical assessment of the feline bronchial and pulmonary vascular structures

The aim of the study was to provide a detailed anatomical study of the feline bronchial and vascular structures by using CT angiography (CTA). Adult cats with no respiratory clinical signs were enrolled in a CTA protocol to provide an anatomical study of the thorax. The dimensions, number of branches and branching pattern (monopodial vs dichotomic) of both bronchial and pulmonary vascular structures were evaluated under positive inspiration apnoea. A linear generalised estimating equations analysis (Spearman's rho) was used to identify statistical correlation between tracheal diameter, age and body weight of the cats. Fourteen cats met the inclusion criteria. The pulmonary arteries had larger diameters than the pulmonary veins, and the pulmonary veins had larger diameters than the bronchial structures. A higher number of segmental bronchial and pulmonary vascular branches was observed in the left caudal lung lobe than in the other lobes. The monopodial branching pattern of both bronchial and pulmonary vascular structures was predominant in all cats of our study (100%) in cranial, caudal and right middle lung lobes, while a dichotomic branching pattern of the bronchial and pulmonary vascular structures of the accessory lung lobe was seen in 13 cats (93%). Thirteen cats (93%) had three pulmonary vein ostia, and one cat (7%) also presented with an additional left intermediate pulmonary vein ostium. Variation in the number of segmental pulmonary vein branches was noted in the right caudal lung lobe. There was no statistical correlation between tracheal diameter, age and weight. Architecture of the feline bronchovascularr structures belongs to a mixed type of monopodial and dichotomic branching pattern. In cats, the pulmonary venous drainage system predominately presents three pulmonary vein ostia. Variations in the type of formation and the number of branches of the pulmonary venous drainage system were noted.

OC32 HYBRID PALLIATION FOR HYPOPLASTIC LEFT HEART SYNDROME AND VARIANTS: A SINGLE CENTER 5-YEAR EXPERIENCE

Background: Hybrid palliation is an alternative to Norwood stage I for the initial management of hypoplastic left heart syndrome (HLHS). We aimed to report our experience with hybrid strategy in HLHS over 5 years in a tertiary care Institution. Methods and Results: Forty-four consecutive patients with HLHS or variants underwent hybrid palliation at a mean age of 2.7 days and mean weight of 3.08 Kg. Balloon atrioseptostomy was required in 5 patients and surgical septectomy in 2 cases. In-hospital death was 11% (5 patients, including 2 preterms and 1 congenital atrioventricular block). Three high-risk patients were diverted to rescue Norwood operation between 37 and 60 days, with 2 early deaths. Interstage mortality was 11% (5 patients, including 1 preterm and 2 intracranial hemorrhage). Fifteen patients required interventional procedures during interstage (mean age 3 months), such as atrial septal dilatation (3 cases) or stenting (7 cases), ductal stent dilatation (9 cases) or restenting (2 cases). Three patients underwent stage II operation in other Institutions. At a mean age of 6 months, 14 patients had comprehensive Norwood stage I-II, whereas 14 received biventricular repair. Survival after surgical stage II was 79% (11 patients) and 93% (13 patients), respectively. All 11 patients after comprehensive I-II and 4/13 after biventricular repair required interventional procedures for pulmonary branches stenosis, either balloon dilatation (16 procedures) or stenting (7 procedures). Four patients underwent Fontan operation and 7 are currently awaiting. Overall survival is 76%. Conclusions: In our experience hybrid palliation has been the treatment of choice for HLHS and variants, unless contraindicated by the presence of aortic reverse coarctation or excessive ductal diameter. Despite the tendency described by the Society of Thoracic Surgeons Congenital Heart Surgery 2015 Database, that institutions with higher hybrid use are expected to have low annual HLHS case volume (&lt;5/year), our average case volume is almost double (9/year). Besides, our in-hospital mortality lies below that reported by STS database. Moreover, hybrid approach resulted in a successful bridge to biventricular repair in as much as 7 patients with hypoplastic mitral and aortic valves, who would have not been eligible for biventricular repair at birth.

Value of Intraoperative Transesophageal Echocardiography during tetralogy of Fallot repair

This study was performed to define a value of intraoperative transesophageal echocardiography (ITEE) during tetralogy of Fallot (ToF) repair.&#x0D; Methods. Intraoperatively 64 patients with ToF were examined by TEE before and after cardiopulmonary bypass (CPB).&#x0D; Results. All preoperative diagnosis were confirmed by ITEE, except two cases when ITEE excluded diagnosis of PA branches’ stenosis and one case when additional muscular ventricular septal defect was detected. Was revealed a strong correlation of PV annulus Z-score diameter by ITEE with intraoperative data (r=0,802; p&lt;0.00001). Significant RVOTO was detected by ITEE in two patients (3,1%) and three patients (4,7%) underwent a reoperation on pulmonary branches due to ITEE data.&#x0D; Conclusions. ITEE imaging is a valuable, safe and accurate tool for anatomical, hemodynamic, and functional assessment during ToF repair.

TCT-326 Catheter Directed Thrombolytic Therapy and Aspiration Thrombectomy in Intermediate Pulmonary Embolism (long term results)

Catheter directed thrombolysis (CDT) and percutaneous thrombectomy (PT) represent well established techniques for the treatment ofintermediate pulmonary embolism (IPE). The purpose of CDT is to dissolve thrombus in the main and distal pulmonary branch. The long-term effect of catheter directed

Evaluation of atrial septal defects with 4D flow MRI\u2014multilevel and inter-reader reproducibility for quantification of shunt severity

PurposeWith the hypothesis that 4D flow can be used in evaluation of cardiac shunts, we seek to evaluate the multilevel and interreader reproducibility of measurements of the blood flow, shunt fraction and shunt volume in patients with atrial septum defect (ASD) in practice at multiple clinical sites.Materials and methodsFour-dimensional flow MRI examinations were performed at four institutions across Europe and the US. Twenty-nine patients (mean age, 43 years; 11 male) were included in the study. Flow measurements were performed at three levels (valve, main artery and periphery) in both the pulmonary and systemic circulation by two independent readers and compared against stroke volumes from 4D flow anatomic data. Further, the shunt ratio (Qp/Qs) was calculated. Additionally, shunt volume was quantified at the atrial level by tracking the atrial septum.ResultsMeasurements of the pulmonary blood flow at multiple levels correlate well whether measuring at the valve, main pulmonary artery or branch pulmonary arteries (r = 0.885–0.886). Measurements of the systemic blood flow show excellent correlation, whether measuring at the valve, ascending aorta or sum of flow from the superior vena cava (SVC) and descending aorta (r = 0.974–0.991). Intraclass agreement between the two observers for the flow measurements varies between 0.96 and 0.99. Compared with stroke volume, pulmonic flow is underestimated with 0.26 l/min at the main pulmonary artery level, and systemic flow is overestimated with 0.16 l/min at the ascending aorta level. Direct measurements of ASD flow are feasible in 20 of 29 (69%) patients.ConclusionBlood flow and shunt quantification measured at multiple levels and performed by different readers are reproducible and consistent with 4D flow MRI.

Upregulated EFNB2 and EPHB4 promotes lung development inanitrofen-induced congenital diaphragmatic hernia rat model.

Congenital diaphragmatic hernia (CDH) is a common congenital malformation associated with high mortality rates, mainly due to pulmonary hypoplasia and persistent pulmonary hypertension following birth. The present study aimed to investigate abnormal lung development in a rat CDH model, and examine temporal and spatial changes in the expression of ephrin type-B receptor 4 (EPHB4) and ephrin-B2 (EFNB2) during fetal lung development, to elucidate the role of these factors during lung morphogenesis. Pregnant rats received nitrofen on embryonic day (E) 8.5 to induce CDH, and fetal lungs were collected on E13.5, E15.5, E17.5, E19.5, and E21.5. The mean linear intercept (MLI) and mean alveolar number (MAN) were observed in fetal lung tissue at E21.5 following hematoxylin and eosin staining. E13.5 fetal lungs were cultured for 96 h in serum-free medium and branch development was observed under a microscope. The gene and protein expression levels of EPHB4 and EFNB2 were assessed by reverse transcription-quantitative polymerase chain reaction analysis, and immunoblotting and immunohistochemistry, respectively. The fetal rat lungs were treated with EFNB2 and the activity of key signaling pathways was assessed. The lung index (lung weight/body weight) at E21.5 was significantly lower in the CDH rats, compared with that in the control fetal rats. The MLI and MAN were also lower in the CDH group. The number of lung terminal buds at E13.5 (embryonic stage), and the lung-explant perimeter and surface were all smaller in the CDH group rats than in the control group at the same age. Pulmonary hypoplasia was observed following 96 h of in vitro culture. No significant differences were found in the expression levels of EFNB2 and EPHB4 between the CDH and control groups at E13.5 (embryonic stage) or E15.5 (pseudoglandular stage), however, EFNB2 and EPHB4 were significantly upregulated at E17.5 (canalicular stage), and at E19.5 and E21.5 (saccular/alveolar stages). EFNB2 stimulated pulmonary branching and EFNB2 supplementation decreased the activity of p38, c-Jun NH2-terminal kinase, extracellular signal-regulated kinase, and signal transducer and activator of transcription. The CDH fetal rats developed pulmonary dysplasia at an early stage of fetal pulmonary development. Upregulated expression of EFNB2 and EPHB4 was observed in the rat lung of nitrofen-induced CDH, and the increased expression of EFNB2 promoted rat lung development in the nitrofen-induced CDH model.

Early and long-term results of biventricular repair of Tetralogy of Fallot with or without pulmonary atresia

After complete repair, the long-term outcome difference between tetralogy of Fallot without pulmonary atresia (TOF) and tetralogy of Fallot with pulmonary atresia (TOF-PA) without MAPCAs is scarcely described. We performed a retrospective study on patients with a diagnostic of TOF and TOF-PA without MAPCAs who underwent complete repair between 1995 and 2016 in our center. We reviewed 960 patients, divided into two main anatomical groups: TOF ( n = 822, 85.7%), and patients with TOF-PA ( n = 138, 14.3%). Concerning surgical technique repair, three groups were distinguished: TOF without transannular patch ( n = 410, 42.7%), TOF/TOF-PA with transannular patch ( n = 494, 51.5%), and TOF-PA with RVOT tube ( n = 56, 5.8%). After complete repair, overall mortality was 11 (1.1%), five of them occurred before discharge (0.5%). Survival at 10 years after repair was 99.1% for TOF and 96.8% for TOF-PA ( P = 0.036). The median follow-up was 10.0 [CI95%: 6.3–14.1] years after repair. One hundred and sixty-three patients underwent reintervention (surgery or percutaneous interventions) (17%). Freedom from reintervention at 10 years after repair was 92.3%, 82.1%, and 48.7% for TOF without transannular patch, TOF/TOF-PA with transannular patch and TOF-PA with RVOT tube respectively ( P < 0.001 between each groups). In addition, reintervention rate was significantly different between TOF with transannular patch and TOF-PA with pulmonary trunk ( P < 0.001). In multivariate analysis, the absence of pulmonary trunk (HR 1.7 IC 95% [1.1–2.6], P = 0.013), pulmonary artery branches stenosis (HR 2.2 IC 95% [1.4–3.5], P = 0.001), prior palliative surgery (HR 2.6 IC 95% [1.8–3.6], P < 0.001), and reintervention before discharge (HR 5.4 IC 95% [3.8–7.5], P < 0.001) were reintervention risk factors. The initial anatomy of pulmonary trunk and branches strongly influences the risk of reintervention in TOF with or without PA. Avoid palliative surgery by directly performing a complete repair in the neonatal period would be a strategical option to improve the prognosis of these patients.

Intraoperative diagnosis with abnormal branching of the left A8 pulmonary artery from the left main pulmonary artery

BackgroundSafety is of vital importance for lung resection. The dissection of pulmonary vessels is associated with vascular injury and bleeding, and identification of the vessels is necessary. The most common abnormal branching pattern of the left pulmonary artery is the mediastinal lingular artery. However, a mediastinal basal pulmonary artery is very rare. A case of abnormal branching from the left pulmonary artery to S8 which was diagnosed intraoperatively, and, thus, its dissection was avoided, is reported.Case presentationA 76-year-old woman with rheumatoid arthritis was diagnosed with left upper lung adenocarcinoma and visited our hospital. Contrast CT was not performed due to renal dysfunction, and abnormal branching of the left pulmonary artery was not identified. Video-assisted thoracoscopic left upper lobectomy and lymphadenectomy were performed. After the upper pulmonary vein was dissected and tissue around it was detached carefully, a pulmonary mediastinal branch from the left main pulmonary artery was identified descending between the upper pulmonary vein and upper bronchus. It was possible to separate the interlobar fissure safely and preserve A8. On retrospective examination, non-contrast CT showed A8.ConclusionsAlthough preoperative identification of left pulmonary mediastinal branches was difficult by non-contrast CT, a careful surgical procedure preserved the left pulmonary mediastinal A8.

Pulmonary vascular anatomy & anatomical variants.

The vessels supplying the lungs include the pulmonary arteries, pulmonary veins, and bronchial arteries. The segmental and sub segmental pulmonary arteries parallel the bronchi and are named according to the bronchopulmonary segments they supply. There are however considerable anatomic variations, particularly in the upper lobes with variations in number or presence of accessory arteries from adjacent segments. The subsegmental pulmonary vein branches, run within interlobular septa and do not parallel the segmental or sub segmental pulmonary artery branches and bronchi. They converge to form right and left superior and inferior pulmonary veins which drain into the left atrium. Knowledge of normal and variant anatomy on cross-sectional and angiographic images is essential for accurate diagnosis of vascular pathology and aids planning of interventional procedures.

Prenatal diagnosis of absent pulmonary valve syndrome by fetal echocardiography: retrospective analysis of 12 cases

Objective To summarize the echocardiographic features of fetal absent pulmonary valve syndrome (APVS). Methods Clinical data and echocardiograms of 12 cases of fetal APVS prenatally diagnosed in the Department of Pediatric Cardiology, Guangdong Cardiovascular Institute from July 2015 to April 2017 were reviewed retrospectively and the echocardiographic features of APVS were summarized. Results Aneurysmal dilation of the main pulmonary artery and branches arteries were found in all cases, causing tracheal and esophageal compression in one case and lung compression in two cases. Color Doppler revealed systolic and diastolic turbulent blood flow with to-and-fro blood flow in pulmonary arteries and pulmonary regurgitation. All fetuses were situs solitus and atrioventricular concordance. Eleven cases were also identified with malposition of the great arteries accompanied with ventricular septal defect, while the other one with normally related great arteries and intact ventricular septum was diagnosed with dysplasia of distal left pulmonary artery and pericardial effusion. Absent ductus arteriosus, increased cardiothoracic ratio and myocardial hypertrophy were found in four, two and five cases, respectively. Fetal umbilical arterial systolic/diastolic ratio and resistance index of all cases were normal. Conclusions Typical APVS is characterized by absent or rudimentary pulmonary valve accompanied with prominant dilated pulmonary arteries, pulmonary valve stenosis and severe pulmonary regurgitation. It is usually accompanied by conotruncal defects, but attention should also be paid to other atypical cardiac abnormalities during screening. Key words: Pulmonary valve; Congenital abnormalities; Pulmonary valve insufficiency; Echocardiography; Ultrasonography, prenatal

Novel aortic arch reconstruction using a modified Norwood procedure based on hypoplastic left heart syndrome-specific anatomical malformations

Postoperative left pulmonary artery (PA) or bronchus compression occasionally follows narrowing of the retroaortic space after the Norwood procedure. We examined hypoplastic left heart syndrome (HLHS)-specific anatomical malformations and hypothesized that a long main pulmonary arterial trunk might contribute to a larger retroaortic space. In this study, we introduced a modified Norwood procedure [pulmonary artery trunk-saving method (PATS)] and evaluated the results. HLHS-specific anatomical malformations were examined using computed tomographic data from 23 consecutive patients who underwent bilateral pulmonary banding. Fourteen patients had HLHS or associated conditions (Group H), and 9 patients had other complex cardiac defects and underwent biventricular repair (Group B). Five consecutive HLHS patients underwent PATS as a modified Norwood operation, and 6 controls underwent a conventional Norwood procedure. We used computed tomography to measure the lengths of the aorta and PA and the angle of both pulmonary branches to evaluate the effect of PATS. Preoperative examination confirmed HLHS-specific right PA branching adjacent to the pulmonary valve and a trend towards a shorter main pulmonary arterial trunk with the conventional Norwood procedure. Also, both right and left pulmonary arterial branching from the dorsal aspect of the main pulmonary arterial trunk and the PA branch angle were minimal in HLHS patients. Postoperative data showed the retroaortic space behind the reconstructed neoaorta was significantly wider in PATS patients than in conventional Norwood patients. Longitudinal measurements (between the aortic arch and pulmonary valve) and sagittal measurements (ascending aorta to descending aorta) were larger in PATS patients, and no left PA or airway obstruction was observed following PATS. PATS resulted in a wider aortopulmonary space without left pulmonary arterial stenosis or bronchus obstruction. HLHS-specific anatomical malformations suggested that PATS may avoid extrinsic compression of the left PA and bronchus by the neoaorta and can be an alternative for HLHS patients.

Normal pulmonary artery and branch pulmonary artery sizes in children.

To establish standards for pulmonary artery and branch pulmonary artery (PA and BPA) effective diameter (ED) and cross-sectional area (CSA) by using computed tomography (CT) data in children of a wide range of sizes and investigate the roundness of arteries. The ED (average of short and long axes) and CSA for the PA and BPA were measured using 1-mm collimation double-oblique reconstructions. Ordinary least squares regression was used to investigate models with various functional forms that related ED and CSA to patient size. Aspect ratio (AR), the short axis divided by long axis, was measured to evaluate roundness. The ideal diameter derived from CSA measurements was compared to ED, short axis, and long axis measurements. 108 CT examinations were analyzed in children without reason for abnormal PA size who ranged in age from 0 to 18years (mean, 10.9years; SD, 5.9years). Interrater reliability was excellent. Data were modeled using a natural log-transformed response variable and a linear term for height as the independent variable. AR for the PA, right pulmonary artery, and left pulmonary artery measured < 0.9 for 38, 55, and 37%, respectively, indicating that many arteries are not round. Ideal diameter was not significantly different than ED but was for short- and long-axis diameter measurements. Normal ED and CSA for PA and BPA were determined for children of different sizes. Measurements outside of the normal range are consistent with dilatation or stenosis. Single diameter techniques are likely to introduce error.

Association Between Tetralogy of Fallot and Tracheobronchial Branching Abnormalities: A New Clue for Pathogenesis?

BackgroundIn our practice, we noticed an increased frequency of tracheobronchial branching abnormalities (TBAs) in patients with tetralogy of Fallot (ToF). This study aimed to determine whether an association exists between congenital TBAs and ToF with or without pulmonary atresia.Methods and ResultsThe frequency of TBAs on chest computed tomography was assessed in 55 patients with ToF without pulmonary atresia, 34 patients with ToF with pulmonary arteria, and 100 control patients. We then looked for a possible association between TBAs and pulmonary artery branch hypoplasia, the presence of major aortopulmonary collateral arteries, and the presence of the chromosome 22q11 deletion. TBAs were significantly more frequent in patients with ToF with or without pulmonary atresia than in the control group (any TBAs, 21% versus 2% [P<0.001]; bronchial situs anomalies, 6% versus 0% [P=0.002]; right tracheal bronchus, 4% versus 0% [P=0.04]; left eparterial bronchus, 8% versus 0% [P=0.005]); and tended to be more frequent in those with ToF without pulmonary atresia than in those with ToF with pulmonary atresia (any TBAs, 27% versus 12% [P=0.11]; left eparterial bronchus, 13% versus 0% [P=0.04]). TBAs were readily multiple (8 patients of 19 with TBA) and concerned essentially the upper lobes. TBAs were not associated with pulmonary branch hypoplasia, major aortopulmonary collateral arteries, or the chromosome 22q11 deletion.ConclusionsWe demonstrated a significantly increased frequency of tracheobronchial abnormalities in patients with ToF with or without pulmonary atresia compared with a control group. These results suggest an interaction between abnormalities in conotruncal septation and tracheobronchial branching and may provide a new clue to the pathogenesis of conotruncal heart diseases.

Hemodynamic impact of pulmonary vasodilators on single ventricle physiology.

The Fontan procedure is the palliative procedure for single ventricle physiology. Pulmonary resistance plays a key role in the success of this operation. There are conflicting data concerning the impact of pulmonary vasodilators on survival and functional capacity among Fontan patients. The aim of this retrospective, single-center, nonrandomized study was to investigate the potential effect of pulmonary vasodilators on pulmonary vasculature in Fontan patients. Twenty-seven patients with single ventricle physiology were enrolled. Eighteen patients were treated with pulmonary vasodilators: 9 patients after Glenn procedure or just after the Fontan completion (Group A) and 9 patients >5years after Fontan completion (Group B). Nine patients after Glenn procedure were enrolled as a control group (Group C). The primary endpoint was to assess changes in hemodynamic profile and pulmonary branches' diameter after 2 right heart catheterizations. Adverse events were recorded. Mean age±SD was 3.2±1.5years (Group A), 26.8±12.7years (Group B), and 3.1±1.0years (Group C). Patients included in Group A had reduced arterial compliance (34.3±15.4 vs 52.2±24.2mm2 /[m2 *mmHg]; P=.03) at baseline compared with Group C. After treatment, Nakata index and pulmonary compliance increased in patients treated with pulmonary vasodilators (Group A), while remaining stable in the control group (Nakata index: +26±24% vs -8±17%, P=.003; pulmonary compliance +80±49% vs -5±30%, P=.001). Similar results were found in Group B (Nakata index: pre-168.6±70.7mm2 /m2 ; post-204.9±97.5mm2 /m2 ; P=.026). Pulmonary vasodilators reduce pulmonary artery resistance and increase vascular compliance, pulmonary artery diameter, and cardiac output in Fontan patients. Therefore, pulmonary vasodilators may be used before the Fontan procedure in patients at high risk of Fontan procedure failure.

Patched1 patterns Fibroblast growth factor 10 and Forkhead box F1 expression during pulmonary branch formation

Hedgehog (Hh) signalling, Fibroblast growth factor 10 (Fgf10) and Forkhead box F1 (Foxf1) are each individually important for directing pulmonary branch formation but their interactions are not well understood. Here we demonstrate that Hh signalling is vital in regulating Foxf1 and Fgf10 expression during branching. The Hedgehog receptor Patched1 (Ptch1) was conditionally inactivated in the lung mesenchyme by Dermo1-Cre in vivo or using a recombinant Cre recombinase protein (HNCre) in lung cultures resulting in cell autonomous activation of Hh signalling. Homozygous mesenchymal Ptch1 deleted embryos (Dermo1Cre+/−;Ptch1lox/lox) showed secondary branching and lobe formation defects. Fgf10 expression is spatially reduced in the distal tip of Dermo1Cre+/−;Ptch1lox/lox lungs and addition of Fgf10 recombinant protein to these lungs in culture has shown partial restoration of branching, indicating Ptch1 function patterns Fgf10 to direct lung branching. Foxf1 expression is upregulated in Dermo1Cre+/−;Ptch1lox/lox lungs, suggesting Foxf1 may mediate Hh signalling effects in the lung mesenchyme. In vitro HNCre-mediated Ptch1 deleted lung explants support the in vivo observations, with evidence of mesenchyme hyperproliferation and this is consistent with the previously reported role of Hh signalling in maintaining mesenchymal cell survival. Consequently it is concluded that during early pseudoglandular stage of lung development Ptch1 patterns Fgf10 and regulates Foxf1 expression in the lung mesenchyme to direct branch formation and this is essential for proper lobe formation and lung function.

EP04.21: Tetralogy of Fallot: a series of cases – associations and evolution

Tetralogy of Fallot has many forms and is frequently associated with other fetal malformations. The evaluation of this pathology's variants, the structural anomalies associations and the fetal or neonatal evolution are observed on a series of cases. A series of 18 fetuses were diagnosed with tetralogy of Fallot, through a period of 7 years, in a tertiary centre from Romania. The gestational age at the time of the echocardiography ranged between 21 and 38 weeks. An amniocentesis was performed in 7 fetuses, out of which one had Down syndrome, two had DiGeorge syndrome, while the remaining four fetuses had a normal karyotype. In three of the fetuses, the tetralogy of Fallot had an extreme variant: one case had a pulmonary valve atresia with severe hypoplasia of the pulmonary branches and MAPCA's, the other was diagnosed with severe pulmonary valve stenosis and pulmonary branch hypoplasia (DiGeorge syndrome) and one fetus had an absent pulmonary valve. Other structural anomalies associations were described in 8 fetuses: bilateral pyelectasis in two of the cases (one with Down, the other with an absent inferior vena cava), hypoplastic thymus in two of the fetuses (with Down and DiGeorge syndrome), unique kidney in one fetus (absence of the pulmonary valve), one fetus with early IUGR and unique umbilical artery (normal karyotype), one case with polycystic bilateral kidney and 2 cases with LPSVC (one of them with MAPCA's). Out of the 18 fetuses, four underwent an TOP (the cases with Down, early IUGR, bilateral polycystic kidney and absence of the pulmonary valve). A number of 7 pregnancies came back to our clinic, and the 7 newborns underwent a cardiac evaluation, followed by surgical interventions which included a systemic-pulmonary shunt. An additional MAPCA's was diagnosed after birth. In conclusion the associations between tetralogy of Fallot and other structural anomalies are frequent, and the MAPCA's diagnosis can't always be intrauterinally established. This research was partially supported by the Collective Research Grants of the University of Medicine and Pharmacy Tîrgu Mureş, Romania (“The role of mother's genetic determinism in child's obesity correlated with bioimpedance and anthropometric parameters” no.275/4/11.01.2017).

A case of large pulmonary embolism in trunk and branches with main manifestation of syncope, vomiting and shock

Pulmonary embolism (PE) refers to the endogenous or exogenous emboli blocking pulmonary trunk or branches, causing clinical and pathophysiological syndrome of pulmonary circulation disorder, the incidence rate is high. Sometimes PE patients were lack of specific symptoms and signs, or without any symptoms, which often result in misdiagnosis, un-timely diagnosis, and the delay of treatment. A PE case with syncope, vomiting and shock, which was proved to be pulmonary artery trunk and branch wide embolism later, was presented so as to improve the understanding of the disease.

EP04.05: Applicability of ISUOG practice guidelines on second trimester sonographic screening examination of fetal heart

To study the applicability of ISUOG practice guidelines on sonographic examination of fetal heart during second-trimester screening. A six month period (July- December 2016) prospective observational study was designed to evaluate singleton pregnancies between 20th and 22ndGW. 327 fetuses were examined. Cases with congenital heart malformation were excluded. Each parameter of the ISUOG heart protocol was scored for accuracy and characterised as adequately or non-adequately assessed by a qualified specialist who performed all examinations. 4 chamber view was adequately imaged in 98.8% of cases (n=323), while left outflow tract imaging was ideal in the total of examined parameters only in 41% of cases (n=134). A right outflow tract sufficient view was in 60.6% of cases (n=198) possible, while three vessel and trachea were characterised as satisfactorily visualised for all examined parameters in 67.6% of cases (n=221). When studying the different 31 parameters included in ISUOG protocol, there were only 5 which seem to be frequently involved in insufficient assessment. These parameters were: AV-valves offsetting (83% adequacy), septoaortic continuity with clear imaging of the aortic root (78.4% adequacy), clear wall demonstration of 3 distinct vessels in 3VTV (67.8% adequacy), detailed pulmonary branching (65.7% adequacy) and optimal visualisation of myocardiac / endocardiac tissue (55.9% adequacy). By excluding those 5 parameters, rate of adequate imaging was raised to 99.2% for 4 chamber view, 98.4% for left outflow tract view,73.8% for right outflow tract view, and 99.2% for three vessel and trachea view. Applicability of most parameters included in ISUOG practice guidelines concerning sonographic screening examination of fetal heart in 2nd trimester is feasible. Myocardiac / endocardiac tissue, AV-valves offsetting, septoaortic continuity, pulmonary artery bifurcation and clear vessel wall borders in 3VTV are indicated to be the parameters which can be characterised as often being inadequately imaged.