Congenital unilateral absence of a pulmonary artery. The importance of flow in pulmonary hypertension

A Curious Case of White Out Lung

CASE PRESENTATION

A 40-year-old Asian man with COPD presented to the ER with an acute exacerbation and type 2 respiratory failure. He was intubated and placed on the mechanical ventilator. He had a tobacco smoking history of 30 pack-years. Otherwise, he had no other significant medical or social history. The family history was non contributory. His physical development was normal.

Proximal interruption of the right pulmonary artery: A rare anomaly

We report a case of a 21-year-old woman with cyanosis where computed tomography (CT) angiography revealed a complete absence of the mediastinal part of the right pulmonary artery with the normal intrapulmonary vascular network, receiving supply from multiple collateral vessels. The case also highlights the various differential diagnoses and the role of CT angiography in arriving at the correct diagnosis.

Proximal interruption of the pulmonary artery: A review of radiological findings

OBJECTIVES

Proximal interruption of the pulmonary artery (PIPA) has various clinical manifestations. This review focused on and summarized the clinical and radiological features of PIPA, based on relevant literature studies.

METHODS

The study included a total of 25 PIPA cases in the Guangzhou Women and Children's Medical Center between January 2015 and December 2021. Conventional chest photographs and chest computed tomography angiography (CCTA) of patients with PIPA were analyzed and summarized.

RESULTS

The radiological results showed that 17 cases were right-sided and 8 cases were left-sided PIPA. Additionally, the percentage of pulmonary hypoplasia on the affected side was 44%, 36% for pulmonary hypertension, 28% for the mosaic sign, 20% for subpleural cystic lucency shadow, 20% for subpleural serrated shadow, 20% for collateral vessel thickening, 16% for subpleural band-like parenchyma, 12% for pneumonia, and 56% for patent ductus arteriosus.

CONCLUSION

The clinical manifestations of PIPA are non-specific. Awareness of this anomaly, based on radiological manifestations, particularly those observed on CCTA images, is important for ruling out alternative diagnoses and implementing appropriate management.

Novel diagnostic and therapeutic approaches to pulmonary hypertension due to the unilateral absence of a pulmonary artery

We report the case of a 64‐year‐old female diagnosed with severe pulmonary hypertension due to the unilateral absence of a pulmonary artery. The four‐dimensional computed tomography scan is a useful modality for revealing detailed anatomical findings for differential diagnoses and surgical decision‐making. The patient had severe pulmonary hypertension with a mean pulmonary artery pressure (PAP) of 74 mmHg and was treated with triple upfront combination therapy, leading to significant improvement in pulmonary haemodynamics (to 27 mmHg in mean PAP) and functional capacity (WHO functional class, from III to II; 6‐min walk distance, from 211 to 276 m).

Unilateral proximal interruption of pulmonary artery with ipsilateral interstitial lung disease - A rare case report

Unilateral proximal interruption of pulmonary artery with ipsilateral occurrence of lung fibrosis is a very rare entity. This case report is about a 27 year old male who had complaints of progressive dysponea since 1 year. He had past history of recurrent lower respiratory tract infections. On auscultation, velcro crackles are heard on right side. Pulmonary function test showed restrictive pattern. Chest Radiography, High Resolution Computed Tomography and CT Pulmonary angiography were performed.

Early single-stage surgical revascularization of pulmonary artery in unilateral absence of a pulmonary artery

Background

This research aims to summarize the findings of the early single-stage revascularization of remnant pulmonary artery in unilateral absent intrapericardial pulmonary artery.

Methods

We retrospectively analyzed the medical records of 10 patients with unilateral absent pulmonary artery, in which 7 were right and 3 were left, the median age and mean weight at surgery was 4 months and 5.6 kg, respectively. The patients received operation from January 2009 to June 2020.

Results

Ten patients, 1 case associated with atrial septal defect, 2 cases with tetralogy of Fallot, and 1 case with aortopulmonary window. The mean diameter of the affected hilar pulmonary artery remnants was 3.14 ± 1.09 mm (1.6-5 mm), and the Z value was − 3.66 ± 1.86 (range, − 6.7 to − 1.75). All the patients received single-stage revascularization: tube graft interposition in 3 patients, autologous pericardial roll in 4, direct anastomosis in one, and main pulmonary artery flap angioplasty in the rest 3. No hospital deaths occurred. Mean follow-up in this cohort was 3.3 ± 1.9 years One case underwent percutaneous balloon dilatation due to new pulmonary artery stenosis. Nonetheless, the results were encouraging, symptoms have improved in all patients. The median Z value of the latest ipsilateral pulmonary artery diameter was − 1.88 (range, − 4.52 to − 1.35), a significantly improvement when compared to the preoperative value. The Z value of that in patients who using Gore-Tex tube increased relatively small.

Conclusions

Single-stage pulmonary artery revascularization is effective at restoring normal antegrade flow to the affected lung, resulting in improved diameter of the PA, regression of pulmonary hypertension, and patient’s symptoms. Revascularization by using the autologous tissue or autologous pericardium may obtain a preferred result. The new pulmonary artery stenosis certainly will need to be addressed in the long-term follow-up.

Long-term outcomes of percutaneous closure of patent ductus arteriosus associated with unilateral absence of a pulmonary artery

OBJECTIVE

This study aimed to evaluate the long-term outcomes of patients with patent ductus arteriosus (PDA) associated with unilateral absence of a pulmonary artery (UAPA).

METHODS

Patients diagnosed with PDA associated with UAPA between January 2005 and June 2019 were retrospectively enrolled in this study. Demographic and clinical characteristics, treatments, and follow-up information were evaluated.

RESULTS

A total of 11 patients were diagnosed with PDA associated with UAPA. Percutaneous closure was successfully conducted in nine patients. The mean diameters of the PDA measured by aortogram and occluders were 5.3 ± 1.8 mm and 11.5 ± 3.9 mm, respectively. The median pulmonary systemic flow ratio (Qp:Qs) in five patients was 1.41, and the median total lung resistance was 12 Wood Units. The mean systolic pulmonary artery (PA) pressure was 68.3 ± 19.1 mmHg. In five patients with pre- and postprocedure catheter data, the systolic pulmonary arterial pressure decreased significantly after closure (from 77.0 ± 20.2 to 58.8 ± 17.5 mmHg; p = .024), as did the mean pulmonary arterial pressure (from 58.2 ± 14.6 to 39.0 ± 14.1 mmHg; p = .18). The PA pressure and heart size gradually decreased to normal levels in eight patients, and their quality of life was significantly improved. The ratio of lung to systemic circulation pressure was less than 0.75.

CONCLUSIONS

In appropriate patients with PDA associated with UAPA, transcatheter closure of PDA has the potential to improve PA hypertension. A ratio of lung to systemic circulation pressure less than 0.75 may be an important reference index for predicting whether PA pressure can be reduced to a normal level after occlusion.

Left pulmonary arterial branch interruption with concurrent coarctation of the right pulmonary artery in a dog

This case report describes a rare disorder of a left pulmonary artery interruption with concurrent coarctation of the right pulmonary artery in a dog. A 5-year-old, male neutered, mixed-breed dog presented for evaluation of an asymptomatic heart murmur. Echocardiography and computed tomography revealed complete interruption of the proximal left pulmonary artery and coarctation of the right pulmonary artery. Collateral circulation to the left lung field was provided by a dilated bronchoesophageal artery with evidence of left pulmonary hypoplasia. Pulmonary artery interruption and coarctation is rarely reported in the veterinary literature.

Recurrent croup in a young child: look beyond airways disease

We reported here a boy aged 5 years who presented for the evaluation of recurrent croup since infancy. On chest examination, breath sounds were reduced throughout the right lung field with a shifting of the trachea and cardiac apex to the right side. The chest radiograph showed a small right lung with decreased vascularity, hyperinflated left lung and mediastinum shifted towards the right side. Flexible bronchoscopy revealed tracheomalacia with left bronchomalacia due to external pulsatile compression. In CT angiogram, the right pulmonary artery (PA) was absent with dilated left PA. Echocardiography did not show any features of pulmonary arterial hypertension (PAH). Since the child was growing well, and there was no limitation of activity and evidence of PAH, he was managed conservatively and kept on follow-up. Though unilateral absent PA is a rare condition, it should be suspected in children with unilateral hypoplastic lung.

Unilateral absence of pulmonary artery associated with lung cancer: analysis of operation strategy based on digital preoperative planning and surgical simulation with three-dimensional visualization

Unilateral absence of a pulmonary artery (UAPA) is a rare congenital anomaly. The occurrence of lung cancer in association with UAPA is even rarer, and clinical experience is very limited. This report aims to describe a case of unilateral absence of the right pulmonary artery that was associated with primary carcinoma of the contralateral lung. Both ipsilateral and contralateral lung cancer operations in patients with UAPA are extremely rare, with limited clinical experience. This article provides insights into the operative tolerability and outcomes after lung surgery in patients with UAPA, with an analysis of the operation strategy based on digital preoperative planning and surgical simulation with three-dimensional (3D) visualization, which may enable lung cancer surgery to be performed safely.

Imaging of the rare cystic lung diseases

When discussing cystic lung diseases, a certain group of diseases tends to receive the majority of attention. Other less frequently discussed cystic lung diseases are also important causes of morbidity in patients. Etiologies include genetic syndromes, lymphoproliferative diseases, infections, exogenous exposures, and a developmental abnormality. This review article focuses on the clinical and imaging features of these other cystic lung diseases.

A case series of three patients with unilateral disconnected pulmonary artery supplied by an ipsilateral patent ductus arteriosus: neonatal ductal stenting as palliation to preserve pulmonary arterial patency

Background 

Disconnected branch pulmonary arteries with a systemic arterial origin of the disconnected vessel is a rare, but well-described entity. Most will have ductal tissue connecting the pulmonary artery to the aorta.

Case summary 

We describe in this paper the haemodynamic result in three neonates presenting with ductal origin of a single branch pulmonary artery in the context of trans-catheter stenting procedures to maintain or re-recruit vessel patency. All were faced with potential or actual ductal closure and proceeded to trans-catheter stenting to re-cannalate the duct-dependent pulmonary artery. Two patients with otherwise normal anatomy struggled post-procedure with pulmonary hypertension and right ventricular dilatation. Both required surgical re-anastomosis of the disconnected pulmonary artery during the same admission—one 26 days post-stenting following failure to wean from high-flow respiratory support and the second 8 days post-stenting following failed extubation. In contrast, a patient with tetralogy of Fallot born at 2.5 kg underwent sequential stenting of the right ventricular outflow tract and then the left-sided ductus. He had a good post-procedural course and thrived for several months before complete repair.

Discussion 

We describe the clinical courses and discuss the resultant haemodynamics, highlighting the importance of flow to each lung, the resulting haemodynamic implications and the compounding effects of additional lesions.

Congenital isolated unilateral agenesis of pulmonary arteries in adults: case series and review

Congenital, isolated unilateral agenesis of pulmonary arteries (UAPA) has a bimodal clinical presentation. It is either diagnosed in early infancy or during adulthood. Early diagnosis and timely surgical correction at infancy prevent the development of irreversible pulmonary hypertension and enable prolonged survival. Though surgical intervention is a conclusive method of treatment, its outcome depends upon the reversibility of pulmonary hypertension and the adequacy of the pulmonary artery dimension. Adults with UAPA can be asymptomatic (diagnosed incidentally) or symptomatic. They may present clinically with myriads of symptoms like exertional dyspnea, recurrent lung infection, hemoptysis, and atypical chest pain. For cases where definitive surgical treatment is not feasible, interventional and medical management should be carried out as part of palliative therapy. A retrospective analysis of 22 cases of UAPA in adults published in the literature from the years 2017-2020 are presented here, along with our institutional case.

Prenatal diagnosis of anomalous origin of one pulmonary artery branch by two-dimensional echocardiography: summary of 12 cases

OBJECTIVES

To improve the prenatal diagnosis for anomalous origin of pulmonary artery branches by comparing and analyzing different types of fetal echocardiography features.

METHODS

Between June 2012 and December 2018, fetal echocardiographic features were analyzed retrospectively from fetuses with a prenatal diagnosis of anomalous origin of pulmonary artery branch. The main points of identification were summarized.

RESULTS

A total of 12 fetuses were diagnosed, including anomalous origin of a pulmonary artery branch from the innominate artery and six cases with unilateral absence of pulmonary artery. The shared characteristic sonographic finding was the lack of confluence at the bifurcation of the main pulmonary artery. The differences between the two conditions are highlighted by the origin of the anomalous vessel. In fetuses with anomalous origin of one pulmonary artery branch, the affected pulmonary artery arose from the posterior wall of the ascending aorta as noted on three vessels and trachea view as well as the long axis of the left ventricular outflow tract. This is in contrast to fetuses with unilateral absence of pulmonary artery, where the origin of affected pulmonary artery arises from the base of the innominate artery via the ipsilateral patent arterial duct as evident on the three vessels and trachea view and the coronal view of innominate (brachiocephalic) artery.

CONCLUSION

(1) The main similarity is an absence of a confluence at the bifurcation of the main pulmonary artery. (2) The main distinguishing feature is the origin of the anomalous vessel from either the subclavian or directly from the aorta.

Isolated absence of the right pulmonary artery with coexisting left-sided heart failure: case report and literature review

Isolated unilateral absence of the pulmonary artery (UAPA) exhibits a benign course and often goes undiagnosed until adulthood. We present a 39-year-old male admitted for left-sided congestive heart failure (CHF) exacerbation. However, chest radiograph demonstrated findings suspicious for UAPA that was ultimately confirmed on computed tomography. Because both CHF and UAPA present similarly with exercise intolerance and dyspnea, a high index of suspicion is required to secure the diagnosis, and in this case, symptoms attributed to CHF may have contributed to delay. A strong awareness of typical radiographic findings allows for initiation of confirmatory tests necessary for a correct diagnosis.

Unilateral interruption of pulmonary artery with pulmonary hypertension: a case for heart lung transplantation?

Unilateral interruption of pulmonary artery is a rare congenital anomaly which is usually associated with other congenital heart disease. Even more rarely it may occur in isolation. Most of the cases are incidentally detected in adulthood. Some cases develop pulmonary hypertension for yet unknown reasons; such cases usually present in infancy with right heart failure. Surgical correction in such cases is associated with adverse outcomes. Heart lung transplantation should be considered in such patients. We report a 3-year-old boy with interruption of right pulmonary artery with severe pulmonary hypertension and right heart failure who was considered for heart lung transplantation.

Unilateral pulmonary artery atresia in an adult: A case report

Intro

Unilateral pulmonary artery atresia (UPAA), while encountered frequently in the congenital cardiac anomaly cohort, is occasionally diagnosed in adulthood after typical symptoms of hemoptysis, pulmonary infection, or as an incidental finding on contrast CT scan. Due to its rarity, a brief discussion of UPAA and its treatment is warranted.

Case report

A 35 year old male presented with three days of hemoptysis. After diagnosis of right UPAA, he underwent angioembolization of 6 large systemic collaterals supplying his right lung, followed by right pneumonectomy. He was discharged on post-operative day 3, and at follow up 6 weeks later was doing well with minimal residual incisional pain and excellent pulmonary reserve.

Conclusions

UPAA presents classically with hemoptysis, but also with pneumonia, pulmonary hypertension, or incidentally. Management includes selective collateral embolization, pneumonectomy, or medical management directed towards decreasing pulmonary hypertension in patients unable to tolerate pneumonectomy due to comorbidities. Pneumonectomy in these patients is characterized by dense and hypervascular adhesions, with large volume blood loss expected during adhesiolysis, which can be decreased with pre-operative embolization. Outcomes are typically excellent in otherwise healthy patients.

Congenital Pulmonary Artery Anomalies: A Review and Approach to Classification

Congenital pulmonary artery anomalies are infrequent but given improved prenatal diagnosis and care, and neonatal surgical advances, over the past two decades are not uncommonly encountered by cardiothoracic imagers. An understanding of their etiology, classifications, associated anomalies, and surgical management can be helpful to avoid under or overdiagnosis. Timely diagnosis assisted by familiarity with imaging findings across modalities and recognition of surgical findings allows for medical management and surgical planning for these patients, with more patients reaching adulthood than ever before.

Neonatal diagnosis of isolated absence of the right pulmonary artery: a case report and review of the literature

Background

Unilateral absence of the pulmonary artery (UAPA) is a rare congenital malformation often associated with other cardiac anomalies; however it may occur as an isolated lesion. Isolated absence of the right pulmonary artery is twice more frequent than that of the left pulmonary artery. Patients with isolated UAPA are usually asymptomatic at birth; thereafter they may develop a progression of symptoms such as exercise intolerance, dyspnea, chest pain, hemoptysis and recurrent pulmonary infections. As patients may remain asymptomatic or have vague symptoms, the diagnosis of isolated UAPA can be difficult to make in infancy. Indeed, most cases described in literature are adults. Due to the rarity of neonatal presentation, there is no consensus regarding the treatment of this malformation.

Case presentation

Herein, the case of a two-day-old term female infant, born after uneventful pregnancy, who required a cardiological assessment for a light murmur, is reported; an echocardiogram demonstrated an isolated unilateral absence of the right pulmonary artery, confirmed by means of magnetic resonance imaging (MRI) performed 1 month after child’s birth. Besides this finding, MRI showed a slightly increased lumen and size of the main and left pulmonary arteries. The right lung was shown to be perfused by some systemic collateral arteries. In the absence of any other cardiovascular malformation, our patient did not need any treatment. As symptoms may occur later in life, a thorough clinical and cardiological follow up was immediately started. Three years later, she is still asymptomatic, showing adequate growth, without any sign of pulmonary hypertension.

Conclusions

Isolated UAPA is a very rare malformation with a diverse clinical presentation. To the best of our knowledge, this is the second case of neonatal presentation of UAPA reported in literature to date. We believe that our case report supports the opinion that a prompt cardiological evaluation is needed whenever a newborn shows signs and/or symptoms of cardiorespiratory concern. Any missed neonatal diagnosis of UAPA may contribute to the later age at presentation, with resultant higher risk of morbidity and mortality and greater therapeutical difficulties.

Isolated unilateral absence of pulmonary artery in adulthood: a clinical analysis of 65 cases from a case series and systematic review

Background

Isolated unilateral absence of pulmonary artery (UAPA) in adulthood is a rare congenital anomaly. Although some case reports exist, the clinical symptomatology, lung parenchymal features, collateral circulation and therapeutic approaches in adult patients with isolated UAPA remain unknown. The objectives of this study are to investigate the clinical characteristics, elucidate the correlation between clinical symptomatology and radiology, and summarize treatment of adult patients with isolated UAPA.

Methods

Cases of adult patients with isolated UAPA who had been diagnosed at our hospital and identified from PubMed, EMBASE and Web of Science from 1990 to 2016 were analyzed.

Results

Hemoptysis was present in 41.5% of patients, exertional dyspnea in 41.5%, and recurrent respiratory infection in 35.4%. Lung parenchymal abnormalities were found on chest computed tomography (CT) scan, including bronchiectasis, which occurred in 30.2% of the patients, interstitial changes in 14.0%, and multiple bullae in 14.0% of the patients. Exertional dyspnea was more frequent in patients with pulmonary hypertension than in those without pulmonary hypertension (P<0.001). Recurrent respiratory infection were more frequent in patients with bronchiectasis than in those without bronchiectasis (P<0.001). Hypertrophic bronchial, phrenic, internal thoracic and intercostal arteries were found in 71.9%, 46.9%, 43.8%, and 43.8% of the patients, respectively. Pneumonectomy reduced hemoptysis in seven cases. Oral phosphodiesterase inhibitors or endothelin receptor antagonist improved exertional dyspnea in three cases with pulmonary hypertension.

Conclusions

Clinicians should be aware of undiagnosed cases of isolated UAPA in adults with unexplained hemoptysis or exertional dyspnea. Early recognition and management of isolated UAPA in adult patients are crucial to avoid the devastating effect of massive hemoptysis or severe pulmonary hypertension (PHT) in the long term.

Paediatric case of ductal origin of right pulmonary artery presenting with exertional dyspnoea and mimicking asthma and primary ciliary dyskinesia

Ductal origin of pulmonary artery is a rare anomaly that is frequently misdiagnosed. Patients may present with exertional dyspnoea, recurrent respiratory infections and pulmonary hypertension. The presence of pulmonary hypertension can adversely affect clinical outcome in these patients; hence, early identification and intervention is the key to improve survival. A case of a 3-year-old child presenting with exertional dyspnoea is presented in this report. Chest radiograph revealed right-sided pulmonary hypoplasia and mediastinal shift to the right. Pulmonary artery agenesis was suspected when CT of the chest demonstrated right-sided pulmonary artery agenesis. Cardiac catheterisation revealed the correct diagnosis of ductal origin of right pulmonary artery. The most striking feature of this case is that the clinical presentation is mild compared with the findings on imaging.

Unilateral absence of pulmonary artery associated with contralateral lung cancer

Unilateral absence of a pulmonary artery (UAPA) is a rare congenital cardiac malformation that is often associated with other cardiovascular deformities. Surgical repair of this rare condition is usually performed only on the abnormal lung. The occurrence of lung cancer in association with UAPA is even rarer and clinical experience is very limited. This report aims to describe a case of unilateral absence of right pulmonary artery that was complicated by primary carcinoma of the contralateral lung. A left lower lobectomy was performed despite the absence of the right pulmonary artery and repeated decreases in the arterial oxygen saturation (SaO₂) were encountered intraoperatively. The current case provides insights into the operative tolerability and the foreseeable ominous prognosis after excision of the normal lung in patients with UAPA and highlights the importance of the clinical awareness of this potentially lethal congenital anomaly in light of its extreme rarity, which may facilitate better diagnosis and treatment of such patients.

Discontinuous Pulmonary Artery

We describe the diagnosis and surgical repair of a five-month-old infant with a congenital discontinuous right pulmonary artery. Initial echocardiogram failed to show the right pulmonary artery and revealed systemic left pulmonary artery pressure based on the tricuspid regurgitation jet. Computed tomographic angiography confirmed the diagnosis of discontinuous right pulmonary artery. The right pulmonary artery appeared essentially normal in size, and there were no significant aortopulmonary collateral arteries. Using cardiopulmonary bypass and aortic transection, we created an anastomosis between the right and the main pulmonary arteries augmented anteriorly by a pericardial patch. Postoperative lung perfusion scan demonstrated balanced pulmonary blood flow to the lungs. Pulmonary hypertension resolved over three weeks in the postoperative period, an expected outcome in this age-group.

Proximal Interruption of the Pulmonary Artery: A Case Series

We present a few cases of Proximal Interruption of the Pulmonary Artery, an uncommon developmental anomaly associated with congenital heart disease. The cases had varied clinical presentations. Chest radiograph showed a hypoplastic lung with an ipsilateral small hilum on the side of the interruption and hyperinflation of the contralateral lung. Contrast CT confirmed the diagnosis, demonstrating non-visualization of the left or right pulmonary artery, and other related findings.

Surgical experience in the rehabilitation and reimplantation of disconnected pulmonary arteries and its effectiveness in restoring pulmonary haemodynamics and function

OBJECTIVES

We established a policy to restore disconnected pulmonary arteries (PAs), regardless of aetiology or cardiac pathology, using a protocol-based strategy. There are conflicting reports of the need to restore disconnected PA especially if severely hypoplastic with some groups advocating surgical repair of cardiac defects to single lung with moderate to high risk.

METHODS

All patients referred to our PA reconstruction programme (2007-14) with complete separation of one branch PA were included. Our surgical strategy was based on the size of the PA. In patients with mild or no PA hypoplasia, we performed single-stage implantation of the disconnected PA and repair of intracardiac defects. Two-stage approach was used in patients with severe PA hypoplasia where the disconnected PA was retrieved inside the lung then connected to the aorta with a shunt to promote growth. After 6-12 months, the PA was implanted with simultaneous repair of intracardiac defects.

RESULTS

Twenty patients were included (age range = 1 week to 8 years). Aetiologies were ductal origin of distal PA in 13 patients and iatrogenic in 7 patients. Group 1 (isolated lesion) consisted of 8 patients who presented with severe pulmonary hypertension. Group 2 consisted of 12 patients with associated intracardiac defects and was subdivided into Group 2a (biventricular hearts) 8 patients and Group 2b (univentricular hearts) 4 patients. Single-stage repair was achieved in 10 patients. Direct tissue-to-tissue connection was achieved in 18 (90%) patients. The follow-up was 100% complete (median = 53.8 months). All patients are alive and asymptomatic. Implanted PAs are patent with good growth demonstrated on serial echocardiography. Only two PAs required balloon dilatation for moderate restenosis at the anastomosis. No surgical reintervention was needed. All Group 1 patients had complete resolution of the pulmonary hypertension. Lung perfusion scans showed increased uptake (24-53% of the total uptake).

CONCLUSIONS

Our study demonstrated that, in paediatric age group, disconnected PAs can be restored with low risk and excellent outcomes even in patients with severely hypoplastic PA. Strategies to repair intracardiac defects to a single lung might not be the optimal approach.

Reconciling paradigms of abnormal pulmonary blood flow and quasi-malignant cellular alterations in pulmonary arterial hypertension

In pulmonary arterial hypertension (PAH) structural and functional abnormalities of the small lung vessels interact and lead to a progressive increase in pulmonary vascular resistance and right heart failure. A current pathobiological concept characterizes PAH as a 'quasi-malignant' disease focusing on cancer-like alterations in endothelial cells (EC) and the importance of their acquired apoptosis-resistant, hyper-proliferative phenotype in the process of vascular remodeling. While changes in pulmonary blood flow (PBF) have been long-since recognized and linked to the development of PAH, little is known about a possible relationship between an altered PBF and the quasi-malignant cell phenotype in the pulmonary vascular wall. This review summarizes recognized and hypothetical effects of an abnormal PBF on the pulmonary vascular bed and links these to quasi-malignant changes found in the pulmonary endothelium. Here we describe that abnormal PBF does not only trigger a pulmonary vascular cell growth program, but may also maintain the cancer-like phenotype of the endothelium. Consequently, normalization of PBF and EC response to abnormal PBF may represent a treatment strategy in patients with established PAH.

Case report of isolated congenital absence of right pulmonary artery with collaterals from coronary circulation

Isolated unilateral absence of a proximal pulmonary main artery is a rare congenital lesion which is often associated with other cardiovascular abnormalities and a diverse clinical presentation. It is usually diagnosed in childhood. Patients who survive into adulthood is uncommon. We report a case of 46 year old hypertensive and obese female who presented with progressive dyspnea. She had features of pulmonary hypertension. The diagnosis was confirmed by CT pulmonary angiography which showed absence of right pulmonary artery and conventional pulmonary angiography which showed ipsilateral lung receiving collaterals from Right coronary artery and its branches. The purpose of this report is to highlight the fact that UAPA, although a rare entity, should be kept in mind in patients with unexplained PAH and prolonged respiratory symptoms unresponsive to routine treatment modalities.

A rare cause of pulmonary hypertension: congenital bilateral atresia of the superior pulmonary arteries and bilateral stenosis of the inferior pulmonary arteries

Bilateral absence (atresia) of the superior pulmonary arteries, combined with bilateral stenosis of the inferior pulmonary arteries, has not to our knowledge been reported before now. We report such a case in a 48-year-old woman, together with the medical and percutaneous catheter interventions used to treat her condition.

Pulmonary artery resuscitation for isolated ductal origin of a pulmonary artery

OBJECTIVE

Ductal origin of a pulmonary artery (DOPA) is commonly misdiagnosed as agenesis of a pulmonary artery (PA), which may result in inadequate treatment. The objective is to describe the results of resuscitation of unilateral DOPA.

METHODS

This study is a retrospective review of all patients with unilateral DOPA who underwent PA resuscitation at Texas Children's Hospital from 1993 to 2012. Patients with other cardiac or contralateral lung anomalies were excluded.

RESULTS

Ten patients, median age 2 years (range, 3 days to 9 years), with unilateral DOPA were included. Symptoms were present in 6 patients. Cardiac catheterization was performed in all and showed a patent duct or a ductal stump in most patients and a small PA on wedge angiography of the pulmonary veins. Two patients underwent single-stage centralization. The other 8 underwent ductal stenting (n=2) or a systemic-to-PA shunt (n=6) as the first stage before centralization. The 2 patients with ductal stenting developed pulmonary edema. The 2 patients with a cryopreserved vein shunt developed early thrombosis requiring reintervention. Nine patients have undergone centralization. Six patients have required further interventional procedures. There have been no deaths. Symptoms and lung hypoplasia have improved in all patients. Median relative lung perfusion at follow-up was 26% (range, 12%-46%) with significant improvement in the size of the affected PA.

CONCLUSIONS

PA resuscitation is effective at restoring flow to the affected lung resulting in improved diameter of the PA, lung growth, and resolution of symptoms. PA resuscitation should be considered in all children with DOPA, including those beyond infancy.

Unilateral absence of pulmonary artery: pathophysiology, symptoms, diagnosis and current treatment

Unilateral absence of pulmonary artery (UAPA) is a rare malformation that can present as an isolated lesion or may be associated with other congenital heart defects. UAPA is often associated with other congenital cardiovascular anomalies, such as tetralogy of Fallot, atrial septal defect, coarctation of aorta, right aortic arch, truncus arteriosus and pulmonary atresia. Diagnosis of UAPA is very difficult and is based on taking a complete medical history, physical examination and imaging examinations. Clinical symptoms include exercise intolerance, haemoptysis and recurrent respiratory infections. Adult patients with UAPA are often asymptomatic. There is no consensus regarding the treatment for UAPA. The therapeutic approach should be based on symptoms of the patient, pulmonary artery anatomy and associated aortopulmonary collaterals. Treatment options for these patients include partial or total pneumonectomy, closure of selected collateral arteries not solely responsible for pulmonary blood flow or a primary versus staged pulmonary artery anastomosis. This review summarizes pathophysiology, symptomatology and current diagnosis and treatment of this disease.

Pulmonary blood flow and pulmonary hypertension: Is the pulmonary circulation flowophobic or flowophilic?

Increased pulmonary blood flow (PBF) is widely thought to provoke pulmonary vascular obstructive disease (PVO), but the impact of wall shear stress in the lung is actually poorly defined. We examined information from patients having cardiac lesions which impact the pulmonary circulation in distinct ways, as well as experimental studies, asking how altered hemodynamics impact the risk of developing PVO. Our results are as follows: (1) with atrial septal defect (ASD; increased PBF but low PAP), shear stress may be increased but there is little tendency to develop PVO; (2) with normal PBF but increased pulmonary vascular resistance (PVR; mitral valve disease) shear stress may also be increased but risk of PVO still low; (3) with high PVR and PBF (e.g., large ventricular septal defect), wall shear stress is markedly increased and the likelihood of developing PVO is much higher than with high PBF or PAP only; and (4) with ASD, experimental and clinical observations suggest that increased PBF plus another stimulus (e.g., endothelial inflammation) may be required for PVO. We conclude that modestly increased wall shear stress (e.g., ASD) infrequently provokes PVO, and likely requires other factors to be harmful. Likewise, increased PAP seldom causes PVO. Markedly increased wall shear stress may greatly increase the likelihood of PVO, but we cannot discriminate its effect from the combined effects of increased PAP and PBF. Finally, the age of onset of increased PAP may critically impact the risk of PVO. Some implications of these observations for future investigations are discussed.

Clinical manifestations and long-term follow-up in pediatric patients living at altitude with isolated pulmonary artery of ductal origin

This study's aim was to define the clinical manifestations and long-term outcome of pediatric patients living at altitude with isolated pulmonary artery (PA) of ductal origin (IPADO). This was a retrospective cohort study of 17 consecutive cases of IPADO at a single center. All patients lived at modest altitude (median 2050 m [range 1700 m to 3050 m]). Fifteen children (88%) were symptomatic at presentation. High-altitude pulmonary edema was present in 2 patients (12%) at diagnosis, and only 1 patient had episodes of hemoptysis during follow-up. Fourteen patients (82%) demonstrated evidence of pulmonary arterial hypertension (PAH). Among 14 patients with PAH, 11 patients had surgical interventions. PAH resolved in 5 of 11 patients (45%) undergoing surgical rehabilitation. One patient died during follow-up, and 7 patients are receiving oral vasodilator therapies due to residual PAH; 14 patients remained asymptomatic. Our study showed that early intervention in patients with IPADO at modest altitude can potentially rehabilitate the isolated PA and reverse PAH. Whether surgery is indicated for patients with this disorder in the absence of PAH is unknown.

Absence of the right pulmonary artery associated with a partial anomalous pulmonary venous connection

Unilateral absence of a pulmonary artery is a rare anomaly. Patients may present with hemoptysis, recurrent respiratory infections, pulmonary hypertension, or congestive heart failure. This report describes the case of a missing right pulmonary artery associated with anomalous left pulmonary venous connection not previously described in the medical literature.

Autologous right pulmonary artery tissue for repair of left pulmonary artery originating from left patent ductus arteriosus in a patient with tetralogy of Fallot and absent pulmonary valve

Left pulmonary artery (PA) originating from patent ductus arteriosus is an exceptionally rare variant of tetralogy of Fallot with absent pulmonary valve. We described an alternative technique for the repair of discontinuous left PA with the use of the redundant pulmonary artery tissue as material for the conduit in a 3-year-old boy.

Right pulmonary artery agenesis presenting with uncontrolled asthma in an adult: a case report

Introduction

Unilateral absence of the pulmonary artery (UAPA) or pulmonary artery agenesis is a rare congenital disorder presenting with a wide spectrum of symptoms. The clinical presentation is variable and many patients can be asymptomatic for many years and even throughout their lives.

Case presentation

We report the case of a 53-year-old African-American woman who was diagnosed with right pulmonary artery agenesis after presenting with uncontrolled asthma and recurrent bronchopulmonary infections.

Conclusion

In an unexplained case of recurrent respiratory infections and shortness of breath, the possibility of a rare congenital anomaly like UAPA should be considered and an appropriate evaluation should be done.

Isolated absence of right pulmonary artery

Background:

Absence of right pulmonary artery (RPA) is a rare congenital abnormality with variable presentation. The diagnosis is often missed in infants

Objective:

The aim of this study was to describe infantile presentation of isolated absence of RPA along with a brief review of the literature.

Methods:

The details of five patients diagnosed with isolated absence of RPA from April 2007 to October 2009 were reviewed retrospectively

Results:

Five patients were identified with this anomaly. The median age of presentation was 86 days (range, 40–120 days) and the median weight was 3.65 kg (range, 3.1–5.5 kg). All patients presented with breathing difficulty and had severe pulmonary hypertension (PHT) along with absent RPA on echocardiography. A multidetector computed tomographic scan was performed to confirm the diagnosis in four cases. Three patients had major aortopulmonary collateral and the hilar RPA was not well developed in all. A correct diagnosis was made before referral in one patient only. Differential vascularity in chest X-ray, a useful clue, was seen in four of five cases. Surgical correction was not considered in view of the small hilar pulmonary artery. The patients were all managed medically with diuretics and Sildenafil.

Conclusion:

Isolated absence of RPA is a rare congenital abnormality with varied presentation. Infantile presentation is marked with congestive cardiac failure and PHT. Specific diagnostic clue includes differential vascularity on the chest X-ray.

Rehabilitation of pulmonary artery in congenital unilateral absence of intrapericardial pulmonary artery

OBJECTIVE

We evaluated the efficacy of the early rehabilitation of remnant pulmonary artery in unilateral absent intrapericardial pulmonary artery and the factors affecting pulmonary artery growth.

METHODS

We retrospectively reviewed the medical records and imaging modalities of 15 patients with unilateral absent intrapericardial pulmonary artery (7 left and 8 right; median age at diagnosis, 5 months) from 1991 to 2008.

RESULTS

The remnant pulmonary artery was found in 12 patients (mean diameter, 2.6 ± 0.7 mm) at the hilum. Eleven patients underwent operation (main pulmonary artery flap angioplasty in 5 patients; tube graft interposition in 6 patients), and 4 patients were inoperable. Transcatheter balloon angioplasty or stent implantation was required for the remaining pulmonary artery stenosis in 6 patients (55%). The last ipsilateral lung perfusion proportion at lung perfusion scan was 39% (range, 15%-51%), and the Z value of the last ipsilateral pulmonary artery diameter was -0.5 (range, -4.2 to 2). The patients with a smaller initial remnant pulmonary artery required more interventions (P = .003). The final perfusion proportion of affected lung was higher in the patients treated early (≤6 months, n = 7) than in those treated late (>6 months, n = 4) (41.9% ± 8.5% vs 24.9% ± 10.7%, respectively, P = .024). The patients with graft interposition showed a lower perfusion proportion of affected lung than those with main pulmonary artery flap angioplasty (P = .017).

CONCLUSIONS

In patients with unilateral absent intrapericardial pulmonary artery, early and aggressive management of combined surgical reconstruction and transcatheter intervention improved pulmonary artery growth and lung perfusion.

Anomalous origin of the pulmonary artery from the aorta: early diagnosis and repair leading to immediate physiological correction

INTRODUCTION

Anomalous origin of one pulmonary artery from the ascending aorta is a rare cardiac anomaly in which the pulmonary artery abnormally arises from the ascending aorta. Physiologically, most patients develop signs of cardiac failure due to high flow to both lungs, with systemic or supra-systemic pressures in the normally connected lung. The purpose of this study is to present our experience with this rare anomaly, in which early anatomic repair lead to rapid physiologic correction.

MATERIALS AND METHODS

Retrospective case review of all patients with anomalous origin of one pulmonary artery from the ascending aorta at Schneider Children's Medical center of Israel between 1986 and 2007. All clinical operative and echocardiographic charts were analysed.

RESULTS

Twelve patients were diagnosed as anomalous origin of one pulmonary artery from the ascending aorta. In 10 patients, the right pulmonary artery rose from the ascending aorta, while in two an anomalous origin of the left pulmonary artery was associated with a right aortic arch. Initial diagnoses was made with two-dimensional echocardiography in all patients. In six patients, diagnostic cardiac catheterisation was performed in order to confirm the diagnosis. Age at diagnosis ranged from 5 to 180 days with a median of 15 days, and patient weight ranged from 780 grams to 5 kilograms, with a median of 3 kilograms. Initial echocardiographic evaluation showed systemic (four patients) or supra-systemic (seven patients) pressures in the right ventricle and normally connected lung. All underwent surgical repair. There was no operative mortality. All reconstructed patients achieved normal right ventricular pressures within days after surgery. The flow pattern in both pulmonary arteries was normalised.

CONCLUSIONS

Early surgical repair of anomalous origin of one pulmonary artery from the ascending aorta is feasible and safe even in newborn and premature babies with complete resolution of the pulmonary hypertension and normalisation of pulmonary vascular resistance.

Age-related clinical characteristics of isolated congenital unilateral absence of a pulmonary artery

Unilateral absence of a pulmonary artery (UAPA) is a rare anomaly. Although UAPA has been reported previously, its age-related pathogenesis and symptoms remain unclear. This retrospective cohort study included cases of UAPA reported in Japan at medical meetings or in the literature from 1990 through 2009. Patients with other congenital cardiac defects were excluded from the study. Clinical status was assessed according to age, and the clinical course of patients with isolated UAPA was compared with that of patients who had UAPA with a patent ductus arteriosus (PDA). Of the 92 patients with UAPA identified, 78 had isolated UAPA (14 with PDA). Hemoptysis and collateral arteries were observed in 0 and 13% of patients with isolated UAPA who were younger than 1 year, as compared with 24 and 50% of those 20 years of age or older, respectively. Pulmonary hypertension was present in 5% of the patients aged 1 to 19 years. Among patients 20 years or older, however, 32% had pulmonary hypertension, and 8% died. Compared with isolated UAPA, UAPA with PDA was associated with an earlier diagnosis (median age, 20 vs. 0 years; p = 0.002), a higher prevalence of pulmonary hypertension (22% vs. 86%; p < 0.0001), and a higher mortality rate (4% vs. 21%; p = 0.046). Collateral artery formation and pulmonary hypertension progress with age in patients with UAPA. Early diagnosis and revascularization may prevent the age-related progression of UAPA.

Ductal origin of the pulmonary artery in isolation: a case series

We present three cases of ductal origin of a pulmonary artery in the absence of associated structural heart disease. No geographic or genetic explanation for the temporal occurrence of these cases could be identified. This series illustrates the importance of angiography in achieving an accurate diagnosis as well as appropriate surgical planning. An understanding of the embryologic origin of this lesion supports the strategic approach at catheterization as well as the surgical choice of interposition graft versus direct anastomosis. We report our experience and highlight diagnostic and surgical approaches to such patients based on the underlying embryology of this congenital cardiac anomaly.

A case of congenital agenesis of the right pulmonary artery presenting with hemoptysis and mimicking pulmonary hemosiderosis

Congenital unilateral absence of a pulmonary artery is a rare anomaly most frequently accompanied by other cardiovascular anomalies. We report a 10-year-old girl presenting with fatigue and recurrent hemoptysis who was initially misdiagnosed with idiopathic pulmonary hemosiderosis. Her symptoms did not resolve despite treatment so she was referred to our center for further evaluation. We carried out an angiography which revealed the absence of the right pulmonary artery and multiple collaterals originating from the right subclavian and right internal mammary arteries supplying the right lung. During the follow-up the patient developed a severe episode of pulmonary infection and pulmonary hypertension which responded well to medical treatment. Physicians should be aware of the congenital absence of the right pulmonary artery especially in patients presenting with recurrent respiratory symptoms. Although this condition is generally considered to have a good prognosis, close observation is mandatory in order to prevent further complications and comorbidities.