Multiple pulmonary arteriovenous malformations in association with Fanconi's syndrome

Asymptomatic Large Pulmonary Arteriovenous Malformation Masquerading as a Metastatic Deposit in a Patient with Papillary Thyroid Carcinoma

Adult cases of congenital arteriovenous malformation (AVM) of the mediastinum are extremely rare, and because of their varied clinical presentations, they pose a diagnostic challenge. There is no reported association of pulmonary AVM and papillary thyroid carcinoma. We describe a 38-year-old female with a large right lung AVM, multinodular goiter, and high serum thyroglobulin (Tg) with papillary thyroid carcinoma. The lung mass was believed to represent a pulmonary metastatic deposit due to high Tg value. Whole body I-131 scan and FDG PETMR imaging were performed as part of the workup.

Pulmonary Arteriovenous Malformations in Non-hereditary Hemorrhagic Telangiectasia Patients: An 18-Year Retrospective Study

PURPOSE

Pulmonary arteriovenous malformations (PAVMs) are most commonly associated with hereditary hemorrhagic telangiectasia (HHT). Patients with PAVMs can present with serious complications including stroke, transient ischemic attack (TIA), and brain abscess. PAVMs are rare in non-HHT patients and little is known about this patient population. The aim of this retrospective study is to better understand clinical presentation and outcomes of PAVMs occurring exclusively in non-HHT patients.

METHODS

Non-HHT patients with PAVMs at the Mayo Clinic-Rochester between 01/01/2000 and 12/31/2018 were reviewed. Patients with Curacao score > 1 were excluded. Demographics, imaging characteristics, neurological complications, and follow-up imaging were analyzed.

RESULTS

Seventy-seven patients with PAVMs were identified. The mean age at diagnosis was 48.2 ± 18.3 years with female preponderance (59.7%). The majority of PAVMs had lower lobe predominance (66.7%) and were simple and single in 75.3% and 89.6% of cases, respectively. Most patients were asymptomatic (46.8%) with dyspnea being the most common symptom (28.6%). Neurologic complications occurred in 19.5% of patients. The majority of PAVMs were idiopathic (61%). Thirty patients (39%) had one or more possible risk factors including previous thoracic surgery (23.4%), congenital heart disease (19.5%), and chest trauma (10.4%). Embolization was performed in 37 (48.1%) patients and only 4 (5.2%) underwent surgical resection.

CONCLUSIONS

Non-HHT PAVMs occur more commonly in females, are most commonly simple and single, and have lower lobe predominance and a high rate of neurologic complications. Potential predisposing risk factors were identified in about 40% of the cases. Clinicians should be aware of the risk of PAVM development in patients with history of chest trauma, congenital heart disease, lung infection/abscess, and thoracic surgery.

Diffuse Pulmonary Arteriovenous Fistulas With Pulmonary Arterial Hypertension: Case Report and Review

Pulmonary arteriovenous fistulas (PAVFs) are rare. Diffuse type PAVFs with pulmonary arterial hypertension (PAH) are even rarer and can elude anatomy imaging like a plain chest film or a computed tomography. The rapid blood flow that ensues due to lack of a capillary bed leads to various degrees of ischemia depending on the number and size of the PAVF. This is a case report of diffuse PAVF in a patient with PAH.This case report describes a patient with recurrent hemoptysis and chest pain. Systemic examination was unremarkable except for P2 attenuation on auscultation. Echocardiograghy showed confirmed pulmonary hypertension with mild dilation of right atrium and ventricle and a tricuspid regurgitation pressure gradient of 40 mm Hg and ruled out congenital heart diseases. Right heart catheterization revealed precapillary PAH with mean pulmonary arterial pressure of 88 mm Hg. Pulmonary angiography showed enlarged pulmonary arterial trunk and diffuse spiral tortuous pulmonary arterial branches indicting diffuse PAVFs. The patient was diagnosed as PAH and began treatment of 25 mg tid of sildenafil.The case highlights a rare and unique presentation of PAH.

A 58-year-old woman with hypoxia, hypoxaemia, a hole in the heart and a … herring! Intracardiac or extracardiac shunt? That is the question!

We describe a case of a previously healthy 58-year-old woman who presented with gradual onset shortness of breath on exertion, erythrocytosis, hypoxia and hypoxaemia. Initial investigations revealed a normal chest radiography and pulmonary function test, however, there was an isolated reduction in diffusion capacity. She was subsequently found to have a patent foramen ovale (PFO) with intermittent shunting. A contrast echocardiography study hinted towards an extracardiac shunt. No shunt was detected in spite of using advanced imaging techniques. A lung biopsy was ultimately performed and histopathology revealed diffuse microvascular pulmonary arteriovenous malformations. This is one of few cases reported of this rare vascular abnormality and highlights its strong genetic association with hereditary haemorrhagic telangiectasia. The diagnostic challenges and management of this unique condition are reviewed in detail.

Pulmonary arteriovenous malformations

Pulmonary arteriovenous malformations (PAVMs) are abnormal vascular structures that most often connect a pulmonary artery to a pulmonary vein, bypassing the normal pulmonary capillary bed and resulting in an intrapulmonary right-to-left shunt. As a consequence, patients with PAVM can have hypoxemia and paradoxical embolization complications, including stroke and brain abscess. PAVMs may be single or multiple, unilateral or bilateral, and simple or complex. Most PAVMs are hereditary and occur in hereditary hemorrhagic telangiectasia, an autosomal dominant vascular disorder, and screening for PAVM is indicated in this subgroup. PAVMs may also be idiopathic, occur as a result of trauma and infection, or be secondary to hepatopulmonary syndrome and bidirectional cavopulmonary shunting. Diagnostic testing involves identifying an intrapulmonary shunt, with the most sensitive test being transthoracic contrast echocardiography. Chest CT scan is useful in characterizing PAVM in patients with positive intrapulmonary shunting. Transcatheter embolotherapy is the treatment of choice for PAVM. Lifelong follow-up is important because recanalization and collateralization may occur after embolization therapy. Surgical resection is rarely necessary and reserved for patients who are not candidates for embolization. Antibiotic prophylaxis for procedures with a risk of bacteremia (eg, dental procedures) is recommended in all patients with PAVM because of the risk of cerebral abscess.

Fanconi anaemia with bilateral diffuse pulmonary arterio venous fistulae: a case report

Background

We report a patient with cytogenetically confirmed Fanconi anaemia with associated diffuse bilateral pulmonary arterio-venous fistulae. This is only the second reported case of diffuse pulmonary arterio-venous fistulae with Fanconi anaemia.

Case Presentation

A 16 year old Sri Lankan boy, with a cytogenetically confirmed Fanconi anaemia was admitted to University Medical Unit, National Hospital of Sri Lanka for further assessment and treatment. Both central and peripheral cyanosis plus clubbing were noted on examination. The peripheral saturation was persistently low on room air and did not improve with supplementary Oxygen. Contrast echocardiography failed to demonstrate an intra cardiac shunt but showed early crossover of contrast, suggesting the possibility of pulmonary arterio-venous fistulae. Computed tomography pulmonary angiogram was inconclusive. Subsequent right heart catheterisation revealed bilateral diffuse arterio-venous fistulae not amenable for device closure or surgical intervention.

Conclusion

To our knowledge, this is the second reported patient with diffuse pulmonary arterio-venous fistulae associated with Fanconi anaemia. We report this case to create awareness among clinicians regarding this elusive association. We recommend screening patients with Fanconi anaemia using contrast echocardiography at the time of assessment with transthoracic echocardiogram. Though universal screening may be impossible given the cost constraints, such screening should at least be performed in patients with clinical evidence of desaturation or when a therapeutic option such as haematopoietic stem cell transplantation is considered. Treatment of pulmonary arteriovenous fistulae would improve patient outcome as desaturation by shunting worsens the anaemic symptoms by reducing the oxygen carrying capacity of blood.

An unusual solitary endobronchial pulmonary arteriovenous malformation in a 10 year-old child

Pulmonary arteriovenous malformations (PAVMs) are relatively rare in children. They may occur both as single isolated anomalies and, much more commonly, as one of many widely distributed arteriovenous malformations (AVMs) in other organs and anatomic locations such as the liver, brain, nose and spine. The latter phenotypically defines the condition known as Hemorrhagic Hereditary Telengiectasia (HHT). We report a case of a 10 year-old female with an isolated endobronchial right lower lobe PAVM. The patient's chest radiograph and fine-cut contrast-enhanced CT (CECT) of the neck and thorax were both uncharacteristically normal and, hence, non-diagnostic. Surgical lobectomy was the only means by which to both diagnose and treat this life-threatening condition. This unique case points out the dilemma facing the physician in such a case with only two management options neither of which is ideal: to either obtain a diagnosis with biopsy which is minimally invasive yet life-threatening due to the potential for fatal hemorrhage, or to perform a pulmonary lobectomy which entails removal of an entire lobe of the lung without a pre-operatively confirmed indication to justify the procedure. To our knowledge, this is the first reported case of a child with an endobronchial PAVM who did not carry the diagnosis of HHT, had normal chest radiography, and had a normal fine-cut CECT of the neck and thorax where such a management dilemma arose. This case points out that a high index of suspicion for PAVMs must be maintained despite normal chest radiography and CECT of the chest. In such cases, empiric lobectomy becomes the sole therapeutic and definitive diagnostic intervention. We hope that such a case published in the literature serves as a guide to physicians confronting similar circumstances as the rarity of such a constellation of variables precludes higher levels of evidence reporting such as a retrospective case series or prospective randomized controlled clinical trials.

Pulmonary arteriovenous fistula within a pulmonary cyst - evaluation with CT pulmonary angiography

Pulmonary arteriovenous malformations (PAVMs) are abnormal direct communications between pulmonary arteries and pulmonary veins. These abnormal communications result in an anatomical right-to-left shunt that reduces the arterial oxygen saturation and may cause hypoxaemia and dyspnoea. Although PAVMs frequently remain undiagnosed, they are associated with severe morbidity in the form of ischaemic strokes and brain abscesses. We report a case of incidental CT angiography depiction of a PAVM within a pulmonary cyst. To the best of our knowledge, no such case has been described previously. On the basis of its appearance and lack of typical clinical features of hereditary haemorrhagic telangiectasia (HHT), we suggest that this PAVM actually represents an acquired fistula from a previously unrecognised focal pulmonary insult, such as trauma or infection, that simultaneously evolved into a pulmonary arteriovenous fistula (PAVF) within a traumatic pulmonary cyst or pneumatocele.

Embolisation des malformations artérioveineuses pulmonaires localisées de l’adulte

OBJECTIVES

To report our experience using embolization in managing localized pulmonary arteriovenous malformations in adults.

MATERIAL

and methods. All patients presenting with localized pulmonary arteriovenous malformations treated with embolization were included in the study. Clinical presentation (respiratory symptoms and previous history of paradoxical embolism) and the characteristics of pulmonary arteriovenous malformations (single or multiple, location, diameter of the afferent artery and simple or complex angioarchitecture) before embolization were analyzed. The details of the procedure, including the number of pulmonary arteriovenous malformations embolized, the number of coils used, and the type of intraoperative complications were recorded. Postembolization clinical and imaging follow-up were described.

RESULTS

Forty-two patients (26 women, 16 men; mean age, 45 years), including 36 with hereditary hemorrhagic telangiectasia were treated with embolization. Twenty-two patients (53%) were dyspneic and 12 (29%) had a previous history of paradoxical embolism prior to embolization. Forty-seven procedures were carried out on a total of 99 pulmonary arteriovenous malformations (mean, 2.3 per patient), using 530 coils (12.6 per patient). The pulmonary arteriovenous malformations were located in the lower lobes in 60% of cases and a simple architecture was reported in 81% of cases. The average diameter of the afferent artery was 6mm. No preoperative complications were reported. After embolization, two patients (5%) presented with a paradoxical embolism and five patients out of 22 (23%) remained dyspneic. The rate of complete occlusion of treated arteriovenous malformations was 92% using computer tomography.

CONCLUSION

Embolization is a highly effective and safe technique for treating pulmonary arteriovenous malformations. Improvement in dyspnea and prevention of paradoxical embolism can be expected. A high technical success rate can be obtained by experienced interventional radiologists.