Diagnosis Of Pulmonary Arteriovenous Malformations Research Articles

Unusual Cause of Hypoxemia During Pregnancy: New Diagnosis of Pulmonary Arteriovenous Malformations

Unusual Cause of Hypoxemia During Pregnancy: New Diagnosis of Pulmonary Arteriovenous Malformations

In vivo hepatic flow distribution by computational fluid dynamics can predict pulmonary flow distribution in patients with Fontan circulation

In Fontan patients, a lung deprived of hepatic blood may develop pulmonary arterio-venous malformations (PAVMs) resulting in shunting, reduced pulmonary vascular resistance (PVR) and decreased oxygenation. To provide guidance for corrective invasive interventions, we aimed to non-invasively determine how the hepatic to pulmonary blood flow balance correlates with pulmonary flow, PVR, and with oxygen saturation. Magnetic resonance imaging (MRI) data from eighteen Fontan patients (eight females, age 3–14 years) was used to construct patient-specific computational fluid dynamics (CFD) models to calculate the hepatic to pulmonary blood flow. This was correlated with pulmonary vein flow, simulated PVR and oxygen saturation. Clinical applicability of the findings was demonstrated with an interventional patient case. The hepatic to pulmonary blood flow balance correlated with right/left pulmonary vein flow (R2 = 0.50), left/right simulated PVR (R2 = 0.47), and oxygen saturation at rest (R2 = 0.56). In the interventional patient, CFD predictions agreed with post-interventional MRI measurements and with regressions in the cohort. The balance of hepatic blood to the lungs has a continuous effect on PVR and oxygen saturation, even without PAVM diagnosis. MRI combined with CFD may help in planning of surgical and interventional designs affecting the hepatic to pulmonary blood flow balance in Fontan patients.

Positive Bubble Study But No Evidence of Interatrial Defect in a Patient with Recurrent Cryptogenic Stroke.

Pulmonary arteriovenous malformations (PAVMs) can be asymptomatic or result in a range of complications such as brain abscesses or cryptogenic emboli, which can contribute to morbidity and mortality if not diagnosed and treated in a timely manner. To date, there have been several reports of delayed diagnosis of PAVMs, which have been largely attributed to the misconception that PAVMs are too rare to be of clinical significance. Furthermore, because intracardiac shunting secondary to a patent foramen ovale (PFO) or atrial septal defect (ASD) also results in a positive saline contrast study with echocardiography, PAVM can be easily misdiagnosed as an intracardiac right-toleft shunt. However, there are unique echocardiographic features that differentiate between intracardiac shunting due to a PFO or ASD and extracardiac shunting such as in PAVM. This case details the course of a patient with recurrent cryptogenic strokes that was initially misattributed to a PFO and was only correctly diagnosed with multiple PAVMs after two failed attempts at PFO closure. This case serves as a reminder of an alternative etiology of right-to-left shunt and its presentation on imaging, which echocardiographers must be familiar with.

Endovascular Embolisation of Pulmonary Arteriovenous Malformation Using Amplatzer Vascular Plugs

Pulmonary arteriovenous malformation (PAVMs) are abnormal communications between pulmonary arteries and veins. The rarity of their occurrence, coupled with the risks they pose, including brain abscess, embolic stroke, and myocardial infarction, mandates that they should not be overlooked in the differential diagnosis of patients presenting with haemoptysis, dyspnea, clubbing, cyanosis, hypoxemia, or epistaxis.We present the case of a 41-year-old local female who presented to our hospital as an outpatient with decreased oxygen saturation (SpO2) of 70%-80% for the past two years with a final diagnosis of PAVM. The initial baseline workup showed polycythemia with a hemoglobin level of 19 mg/dL and raised hematocrit. She had extensive workup in the past two years for her polycythemia including gene mutation testing and cardiac workup which all turned out normal. Her chest X-ray (CXR) showed right lung opacity which was initially considered to be infective but it did not respond to antibiotic treatment. Later on, a CT scan of the chest was performed and findings were typical of a large PAVM which had two feeding arteries. The patient was referred to a cardiothoracic surgeon who sent the patient to the interventional radiology section for endovascular management.The embolization procedure was then performed and both feeders were successfully embolised. After the procedure, the patient's SpO2 levels were restored to 95%-96%, and no post-procedure complications were noted.

Clinical example of surgical treatment of arteriovenous malformation in right thoracoscopic lobectomy

Pulmonary arteriovenous malformations are a rare congenital pathology observed in 2–3 individuals per 10,000, and 10 % of cases are diagnosed in children in the first several years of life. Arteriovenous malformations are vascular abnormalities of the cardiovascular system presenting as pathological anastomoses (shunts) between the arterial and venous systems which leads to direct shunting of nonoxygenated blood from the arterial bed into the venous bed bypassing pulmonary capillary network. Frequently, diagnosis of pulmonary arteriovenous malformations is made in rather neglected cases. Pulmonary arteriovenous malformations is hard to diagnose and treat, therefore it requires special attention from surgeons and clinicians which prompted us to describe a clinical case of a young 27-year old male patient with signs of significant chronic hypoxia (saturation (SpO2 ) – 84–86 %, hemoglobin level – 185 g/L, erythrocyte count – 6.13 million/μL, hematocrit – 51.8 %; during examination: acrocyanosis, nail clubbing; complaints of vertigo, decreased tolerance of physical activity, breathlessness during physical activity). Computed tomography in the S8, S9 segments showed arteriovenous malformation, size about 70 × 70 mm. Patient underwent radical treatment in the form of right lower thoracoscopic lobectomy which led to an immediate increase in oxygen saturation (SpO2 ) to 99 %. This clinical example shows that surgical method of treatment is the most radical, and thoracoscopic intervention in a young patient significantly decreases the volume of injury and promotes quick recovery and return to active life.

Acquired pulmonary arteriovenous malformation associated with bronchiectasis: a case report

BackgroundPulmonary arteriovenous malformations are mostly caused by congenitally abnormal shunts between pulmonary arteries and pulmonary veins.Case presentationA 74-year-old Japanese woman with a history of bronchiectasis was admitted to our hospital because of dyspnea on exertion. Pulmonary angiography and reconstructed three-dimensional contrast-enhanced computed tomography images showed shunts between pulmonary arteries and pulmonary veins, indicating a diagnosis of pulmonary arteriovenous malformations. Coil embolization of the shunts was successful.ConclusionsOur findings imply that bronchiectasis can cause pulmonary arteriovenous malformations, and thus patients who present with hypoxemia with bronchiectasis should be carefully evaluated.

CT Appearance of Pulmonary Arteriovenous Malformations and Mimics.

A pulmonary arteriovenous malformation (PAVM) is a fistulous connection between a pulmonary artery and a pulmonary vein that bypasses the normal pulmonary capillary bed resulting in a right-to-left shunt. Because of the potential for paradoxical emboli, PAVMs are treated when their feeding arteries exceed 3 mm or patients are symptomatic. PAVMs are often encountered in patients with suspected hereditary hemorrhagic telangiectasia (HHT). Sporadic cases are uncommon. The radiologist may be called on to diagnose a PAVM after positive transthoracic contrast-enhanced echocardiography in a patient with suspected HHT to direct patient management and avoid potential complications. The radiologist may also be required to evaluate a potential PAVM detected at CT performed for other reasons. Through the authors' experiences at an HHT Center of Excellence in an area endemic with histoplasmosis, the authors have gained a unique perspective on the diagnosis of PAVMs and differentiation of PAVMs from their mimics. Understanding the CT appearance of PAVMs limits misdiagnosis, directs appropriate treatment, and allows subsequent family screening for HHT (and avoidance of unnecessary screening when a PAVM mimic is encountered). Both vascular and nonvascular pulmonary lesions can mimic PAVMs. Vascular mimics include fibrosing mediastinitis, venovenous collaterals, arterial collaterals, pulmonary artery pseudoaneurysms, hepatopulmonary vessels, Sheehan vessels, meandering pulmonary veins, and pulmonary vein varices. Nonvascular mimics include granulomas, nodules, mucoceles, bronchoceles, ground-glass opacities, and atelectasis. The authors review the CT technique for evaluating PAVMs and the appearance of PAVMs and their mimics. ©RSNA, 2022.

Pulmonary Arteriovenous Malformation and Its Vascular Mimickers.

Pulmonary arteriovenous malformation (AVM) is a congenital vascular disease in which interventional radiologists can play both diagnostic and therapeutic roles in patient management. The diagnosis of pulmonary AVM is simple and can usually be made based on CT images. Endovascular treatment, that is, selective embolization of the pulmonary artery feeding the nidus of the pulmonary AVM, and/or selectively either the nidus or draining vein, has become a first-line treatment with advances in interventional devices. However, some vascular diseases can simulate pulmonary AVMs on CT and pulmonary angiography. This subset can confuse interventional radiologists and referring physicians. Vascular mimickers of pulmonary AVM have not been widely known and described in detail in the literature, although some of these require surgical correction, while others require regular follow-up. This article reviews the clinical and radiologic features of pulmonary AVMs and their mimickers.

English

Pulmonary arteriovenous malformation (PAVM) is one of the rare pulmonary vascular anomalies. Pulmonary arteriovenous malformation results in right to left shunt due to the abnormal communications between the pulmonary arteries and the pulmonary veins bypassing the normal capillary bed.1 This condition being rare could be easily missed, hence, it is essential for clinicians to suspect it based on the classical clinical features. This helps in early diagnosis and deciding further appropriate treatment option. Here we report the case of a patient affected by a large idiopathic pulmonary arteriovenous malformation in the right lung. Most patients with pulmonary arteriovenous malformation are asymptomatic. This is due to the chronic compensation and secondary erythrocytic response. Dyspnoea due to PAVMs are a result of right-to-left shunt. Initial diagnostic tools include chest radiography and contrast enhanced computed tomography but the gold standard is pulmonary angiography.2 Because AVM has substantial morbidity rates associated with it, all patients with PAVMs who can undergo embolization should be treated with transcatheter embolization. In rest of the patients, surgical excision should be considered. The main objective of this study was to highlight the early suspicion and diagnosis of pulmonary arteriovenous malformation as this is easily missed and leads to undue delay of treatment.

Amplatzer Vascular Plug Occlusion in a Child with Late-diagnosed Multiple Pulmonary Arteriovenous Malformations

Pulmonary arteriovenous malformations (PAVMs) are abnormal direct connections between the pulmonary artery and pulmonary vein, which may result in a right to left shunt. Patients may be asymptomatic, but symptoms may gradually occur with the enlargement of the fistula. A 5-year-old Syrian female patient was followed by the primary care physician during the last year with a diagnosis of polycythemia. The patient reported headache and abdominal pain for the last three months and was referred to the pediatric cardiology outpatient clinic when clubbing was detected. Normal sinus rhythm was observed in electrocardiography and echocardiographic examination findings were normal. Thoracic computed tomography/angiography was performed and PAVM was detected in the upper segment of the lower left lobe. Catheter angiography was performed with the diagnosis of PAVM. The fistulas were closed using three vascular plugs. Transcutaneous oxygen saturation increased to 96% after the procedure.

HIDDEN IN PLAIN SIGHT: NEW DIAGNOSIS OF PULMONARY ARTERIOVENOUS MALFORMATION AFTER ISCHEMIC COLITIS

SESSION TITLE: Medical Student/Resident Pulmonary Vascular Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Pulmonary arteriovenous malformation (PAVM) is an abnormal connection between a pulmonary artery and vein, which allows blood to bypass the filter function of the capillary beds and delivers deoxygenated blood to the left heart. This condition often remains undiagnosed until thromboembolic complications present. We report the case of new diagnosis of PAVMs in a patient presenting with ischemic colitis. CASE PRESENTATION: A 58-year-old female presented with acute onset diffuse abdominal pain and emesis. She was afebrile and normotensive with nonspecific abdominal tenderness on examination. Laboratory data was significant for mild leukocytosis and normocytic anemia. Computer Topography (CT) abdomen and pelvis showed diffuse inflammation around the cecum, consistent with ischemic colitis. She underwent partial colectomy with ileostomy placement. Postoperatively, she developed acute hypoxemia. CT angiogram showed left lower lobe pulmonary embolus and multiple PAVMs (largest in left lower lobe). She was treated with anticoagulation. However, she remained hypoxic and required oxygen at discharge. Further history revealed episodic epistaxis since childhood, three prior stillbirths, miscarriage, and multiple strokes in her sister. Hypercoagulable work-up was negative. She was readmitted multiple times for hypoxia and has undergone numerous PAVM embolization procedures. Post-embolization bubble echocardiogram showed intra- and extra-cardiac shunt both confirmed by transesophageal echocardiogram. DISCUSSION: Most PAVMs are hereditary with over 80% occurring in association with hereditary hemorrhagic telangiectasia, an autosomal dominant vascular disorder. Less commonly, PAVMs are idiopathic or secondary to trauma, infection or due to hepatopulmonary syndrome. Previously viewed as rare conditions, recent data suggest PAVMs affect 1 in 2,600. Patients with PAVMs present with hypoxemia and paradoxical embolization complications, including stroke, brain abscess, and other end-organ ischemia as seen in our patient who presented with ischemic colitis. A history of recurrent nosebleeds since childhood and family history of strokes were subtle clues to the diagnosis, but as in many other cases, the PAVMs were not identified until she presented with a paradoxical thromboembolic event. Patient has persistent hypoxemia despite embolization, and we hypothesize that obliteration of the large PAVMs led to elevated pulmonary pressures, which opened the intra-cardiac shunt in addition to new intra-pulmonary shunts. CONCLUSIONS: Pulmonary AVMs often remain undetected in patients until a thromboembolic complication occurs. Increased awareness of variable presentations of pulmonary AVMs is essential for prompt diagnosis and treatment to prevent devastating complications. Reference #1: Shovlin, C. Pulmonary arteriovenous malformations. Am J Respir Crit Care Med. 2014 Dec 1; 190 (11): 1217-1228. Reference #2: Lovering, A et al. Pulmonary pathways and mechanisms regulating transpulmonary shunting into the general circulation: An update. Injury. 2010 Nov; 41(0 2): S16-S23. Reference #3: Lee, W et al. Contrast echocardiography remains positive after treatment of pulmonary arteriovenous malformations. Chest Journal. 2003 Feb; 123 (2): 351-358. DISCLOSURES: No relevant relationships by RAMYA GORTHI, source=Web Response No relevant relationships by John Mwangi, source=Web Response No relevant relationships by Mackenzie Steck, source=Web Response

Abstract No. 417 Arteriography of pulmonary arteries for pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: national trends, patient characteristics, and outcomes

to examine the national estimates for admission of patients with hereditary hemorrhagic telangiectasia (HHT) who were diagnosed with pulmonary arteriovenous malformations (PAVMs) and received arteriography of pulmonary arteries (PA arteriography) during their inpatient stays. Data from the National Inpatient Sample (NIS) 2012–2015 was used for this study. A survey analysis approach was used to calculate nationally representative estimates of inpatient stays of HHT patients with PAVM diagnosis. Patient and hospital characteristics, as well as short-term outcomes were compared based on PAVM diagnosis and need for PA arteriography. HHT patients were responsible for an estimated 4210 to 4450 number of admissions per year (2012–2015), 4.3% to 7.6% of which were related to a PAVM diagnosis and 1.0% to 2.0% of them required PA arteriography (45-85 per year). HHT patients with PAVM who received PA arteriography were younger (43.1 ± 3.6 vs. 60.0 ± 0.4), were more likely to be female (69% vs. 58%) and had lower frequency of chronic blood loss anemia (6% vs. 14%), congestive heart failure (3% vs. 17%), chronic pulmonary disease (14% vs. 26%) and coagulopathy (3% vs. 8%) when compared to an average pool of HHT admissions. PA arteriography was more frequently performed in large (80.0%), private-owned (85.7%), and urban teaching (91.4%) hospitals. PA arteriography admissions were associated with no significant mortality (frequency <0.1%), an average 7.4 ± 1.5 days of in-hospital stay, 77.1% routine disposition, and total hospital charge of 141,742 ± 27,994 USD. PA arteriography for PAVM in HHT patients is an uncommon procedure (1.0%-2.0% of all admissions of HHT patients), that is more commonly performed in patients with better comorbidity profiles and is associated with limited mortality.Tabled 1National Outcomes for HHT Admission According to PAVM and PA ArteriographHHTHHT + PAVMHHT + PAVM Receiving ArteriographyDied (%)2.0 (0.2)2.0 (1.1)<0.1 (<0.1)Length of Stay (days)4.6 (0.1)5.5 (0.5)7.4 (1.5)*Routine discharge (%)68.0 (0.9)71.4 (3.6)77.1 (0.7)*Total charges (USD)44,190 (1505)55,282 (4654)141,742 (27,994)**P for trend <0.05. Open table in a new tab

Pulmonary arteriovenous malformations: what the interventional radiologist needs to know.

Pulmonary arteriovenous malformations (PAVMs) or fistulas are rare direct pathological connections between pulmonary arterial and venous circulation. Most of PAVMs are congenital and closely associated with hereditary hemorrhagic telangiectasia, but acquired PAVMs have also been described in the literature. Diagnosis of PAVMs is a priority for clinicians, in order to prevent potentially fatal events such as cerebrovascular stroke, systemic septic embolization, hemoptysis and hemothorax. In this scenario, the radiologist plays a key role in both diagnostic and therapeutic workups of PAVMs: Chest X-ray, computed tomography and magnetic resonance are effective tools for PAVMs identification and confirmation of the suspected diagnosis. Furthermore, imaging modalities provide most of the elements for PAVMs classification according to their angioarchitecture (simple and complex) and help the clinicians in establishing which lesion requires prompt treatment and which one will benefit of imaging follow-up alone. Endovascular management of PAVMs has grown up as the first-line treatment in respect of surgery during last decades, showing lower risk of intra- and post-procedural complications and offering a wide number of treatment options and materials, ensuring effective management in virtually any clinical situation; interventional treatment aims to exclude PAVMs from pulmonary circulation, and specific technique and embolic agents should be selected according to pre-treatment imaging, in order to obtain the best procedural outcome. This paper proposes a review of the clinical and radiological features that a radiologist needs to know for PAVMs diagnosis and proper management, also showing an overview of the most common endovascular treatment strategies and embolization materials.

Cerebral Abscess Associated With Odontogenic Bacteremias, Hypoxemia, and Iron Loading in Immunocompetent Patients With Right-to-Left Shunting Through Pulmonary Arteriovenous Malformations.

Cerebral abscess is a recognized complication of pulmonary arteriovenous malformations (PAVMs) that allow systemic venous blood to bypass the pulmonary capillary bed through anatomic right-to-left shunts. Broader implications and mechanisms remain poorly explored. Between June 2005 and December 2016, at a single institution, 445 consecutive adult patients with computed tomography-confirmed PAVMs (including 403 [90.5%] with hereditary hemorrhagic telangiectasia) were recruited to a prospective series. Multivariate logistic regression was performed and detailed periabscess histories were evaluated to identify potential associations with cerebral abscess. Rates were compared to an earlier nonoverlapping series. Thirty-seven of the 445 (8.3%) patients experienced a cerebral abscess at a median age of 50 years (range, 19-76 years). The rate adjusted for ascertainment bias was 27 of 435 (6.2%). Twenty-nine of 37 (78.4%) patients with abscess had no PAVM diagnosis prior to their abscess, a rate unchanged from earlier UK series. Twenty-one of 37 (56.7%) suffered residual neurological deficits (most commonly memory/cognition impairment), hemiparesis, and visual defects. Isolation of periodontal microbes, and precipitating dental and other interventional events, emphasized potential sources of endovascular inoculations. In multivariate logistic regression, cerebral abscess was associated with low oxygen saturation (indicating greater right-to-left shunting); higher transferrin iron saturation index; intravenous iron use for anemia (adjusted odds ratio, 5.4 [95% confidence interval, 1.4-21.1]); male sex; and venous thromboemboli. There were no relationships with anatomic attributes of PAVMs, or red cell indices often increased due to secondary polycythemia. Greater appreciation of the risk of cerebral abscess in undiagnosed PAVMs is required. Lower oxygen saturation and intravenous iron may be modifiable risk factors.

Pulmonary Arteriovenous Malformation Causing Systemic Hypoxemia in Early Infancy

Pulmonary arteriovenous malformation (AVM) is not routinely appreciated during the standard echocardiogram to assess for structural abnormalities or pulmonary hypertension. The distal pulmonary AVM is suspected only if an injection of agitated saline is performed and late entry of particles is appreciated in the left heart structures. A large or complex pulmonary AVM can result in significant right-to-left shunting and consequential systemic hypoxemia in the presence or absence of pulmonary hypertension. For direct visualization of the pulmonary AVM, computerized tomography (CT) scan is the procedure of choice. Here, we present two young infants with systemic hypoxemia who underwent standard medical management including mechanical ventilation and one patient was placed on extracorporeal membrane oxygenation (ECMO) before the diagnosis of pulmonary AVM was established. Subsequently, both patients have done well into mid-term follow-up after being treated successfully using transcatheter occlusion techniques in the cardiac catheterization laboratory during early infancy. We aim to emphasize the importance of a high index of suspicion for pulmonary AVM in infants with refractory systemic hypoxemia of unclear etiology.

Surgical treatment of pulmonary arteriovenous malformations.

Pulmonary arteriovenous malformations (PAVMs) are direct communications between the branches of pulmonary arteries and veins. This study evaluates surgically treated cases of pulmonary arteriovenous malformations. We retrospectively examined 41 cases of PAVM that were operated in our clinic between 1995 and 2012. We obtained the clinical, radiological, and surgical data of the patients from their files. The 41 cases comprised 27 males and 14 females. Their mean age at diagnosis was 39.8 years (range: 9-71). The symptoms were hemoptysis in 28 cases, dyspnea in five, cough in three, and epistaxis in two; three patients were asymptomatic. Twenty-three right and 19 left posterolateral thoracotomies were performed, including one case which was operated bilaterally. Lower lobectomy was performed in 17 patients, lower lobectomy and lingulectomy in two, upper lobectomy in ten, middle lobectomy in two, segmentectomy in seven, and wedge resection in four. Postoperative histopathology was arteriovenous malformation in all cases. PAVMs are rare clinical conditions. Surgery remains the first choice when embolization treatment cannot be performed or is not successful, in symptomatic and complicated patients with PAVM, and/or in cases where the PAVM diagnosis cannot be established.

Pulmonary arteriovenous malformation-etiology, clinical four case presentations and review of the literature.

Pulmonary arteriovenous malformation (PAVM) is a rare clinical condition with abnormal direct communication between the branches of pulmonary artery and vein. It may occur as an isolated anomaly or in association with hereditary hemorrhagic telangiectasia (HHT). Although these vascular pulmonary pathologies are quite uncommon, they are the important part of the differential diagnosis of common pulmonary problems such as hypoxemia and pulmonary nodules. The diagnosis of PAVM in patients remains a diagnostic challenge to the emergency physician. The most common clinical signs of PAVM are recurrent episodes of epistaxis and hemoptysis, so surgical resection is deemed the best curative option to avoid further episodes and recurrence of hemoptysis. Quite often the diagnosis is established after pathohistological examinations. We report a case of a female patient with a massive recurrent hemoptysis and without pathologic radiological findings which would suggest to PAVM and who was successfully treated with lobectomy.

Pulmonary arteriovenous malformation mimicking a pulmonary tumour on (18)F-fluorodeoxyglucose positron-emission tomography/computed tomography.

Pulmonary arteriovenous malformations are rare congenital abnormal connections between the pulmonary arteries and veins. The patients are usually asymptomatic [1]. Although their aetiology is unclear, it is presumed that genetic abnormalities constitute a predisposition [1, 2]. An arteriovenous malformation might cause serious complications if it remains undiagnosed and untreated [3]. We report a unique case of focal 18F-fluorodeoxyglucose (18F-FDG) uptake in a pulmonary arteriovenous malformation mimicking a mass lesion. A 74-year-old female patient with cyanosis and clubbing in her fingers and toes was referred to the Nuclear Medicine Department for positron-emission tomography (PET)/computed tomography (CT) imaging to assess a solitary pulmonary nodule with irregular margins in the right upper lobe detected on CT (Figure 1A). The CT appearance suggested a malignant lesion. On 18F-FDG PET/CT, there was increased focal uptake in the pulmonary nodule, suggesting a mass lesion, possibly malignant (Figure 1B). There is no described typical uptake pattern for arteriovenous malformations in FDG PET/CT images. 18F-FDG accumulation in a pulmonary mass suggests malignancy in most cases, although FDG accumulates in several benign conditions. Pulmonary angiography revealed afferent and efferent vessels with high contrast accumulation. Based on these findings, a pulmonary arteriovenous malformation was diagnosed. Subsequently, the patient underwent right video-assisted thoracoscopic surgery, a mini-thoracotomy, and wedge resection. The specimen confirmed the diagnosis of pulmonary arteriovenous malformation (Figure 2). Figure 1 A – CT image showing a solitary pulmonary nodule in the anterior segment of the upper pole of the right lung. B – On 18F-FDG PET/CT, increased focal uptake was seen in the pulmonary nodule, suggesting a malignancy (SUVmax 4.2 kBq/ml) Figure 2 The specimen was stained with (A) haematoxylin and eosin and (B) Elastica van Gieson, which showed large and small vessels, confirming the diagnosis of pulmonary arteriovenous malformation Pulmonary arteriovenous malformations are often diagnosed radiologically [4–6]. A chest X-ray might reveal a solitary nodule or be completely normal. Thorax CT is usually the second diagnostic tool in a patient with a suspected pulmonary arteriovenous malformation [7, 8], which causes dyspnoea and cyanosis in most cases [1, 3]. Pulmonary angiography gives the ultimate diagnostic information [4, 8]. The CT appearance of our patient's arteriovenous malformation suggested a malignant solitary mass. The moderately increased FDG uptake also caused diagnostic confusion. There is no typical uptake pattern of arteriovenous malformations in FDG PET/CT images.

Endovascular Management of Pulmonary Arteriovenous Malformation

Although many studies showed that pulmonary arteriovenous malformations (PAVM) are relatively rare disorders, they are still an important part of differential diagnosis of common pulmonary problems such as hypoxemia, dyspnea on exertion and pulmonary nodules. A thirty-five-year-old female patient presented with low oxygen saturation six hours post simple vaginal delivery. The patient was investigated by echocardiography, chest x-ray and CT pulmonary angiography, which confirmed the diagnosis of pulmonary arteriovenous malformations (PAVM). Pulmonary conventional angiogram with transcatheter coil embolization was performed to treat the condition. The patient had uneventful recovery following coil embolization of pulmonary arteriovenous malformations.

P83 Should children from HHT families undergo screening thoracic CT scans for the diagnosis of pulmonary arteriovenous malformations? Survey data on breast cancer incidence

BackgroundLimiting thoracic radiation burden is a driving force for development of diagnostics, with the use of childhood CT scans particularly linked to increased cancer incidence [1]. Imaging of children with...