Concurrent pulmonary arteriovenous malformation and pulmonary embolism causing stroke: a therapeutic dilemma

Background As pulmonary arteriovenous malformation (PAVM) include a right-to-left shunt, it can be accompanied by fatal complications such as stroke and brain abscess due to paradoxical embolism. A concurrent PAVM and pulmonary embolism (PE) is a rare condition. Therefore, the sequence of management has not been established. Case presentation A 62-year-old female patient was transferred to our hospital with a sporadic simple PAVM and concurrent bilateral PE. On chest computed tomography (CT), the acute PE was extended to the segmental pulmonary artery where the feeding artery of PAVM originated. Despite the anticoagulation, the patient complained of left sided weakness on the fifth day of admission, and magnetic resonance imaging revealed an acute infarction in the right lateral thalamus, which was thought to be caused by paradoxical embolism. This situation could lead to a dilemma between the risk of thrombus migration during PAVM embolization and another embolic event due to delayed shunt occlusion during anticoagulation. After a multidisciplinary discussion, a delayed endovascular embolization was performed for PAVM after confirming the complete resolution of PE with 4 months of anticoagulation. The cause of PE in this patient was eventually diagnosed as antiphospholipid syndrome. Conclusion The authors reported a rare case of concurrent PAVM and PE that led to an embolic stroke during hospitalization. This patient was managed with delayed endovascular embolization for PAVM after an anticoagulation for PE and stroke. It is thought to be valuable in deciding for a treatment plan for this rare condition.

Pearls & Oy-sters: Cerebral Abscess Secondary to Pulmonary Arteriovenous Malformation in Hereditary Hemorrhagic Telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal-dominant condition which is linked to a myriad of neurological complications arising from vascular malformations of the brain, spinal cord, and lungs. Our case describes a previously healthy 3-year-old male who presented to hospital with fever of unknown origin and was found to have a brain abscess stemming from a pulmonary arteriovenous malformation (PAVM). This etiology was identified after a period of diagnostic delay; the medical team was suspicious for a proximal embolic source due to the presence of multiple tiny infarcts seen on MRI brain, but transthoracic echocardiogram and head and neck angiogram were unremarkable. Fortunately, an enhanced CT chest was performed, identifying a moderately-sized PAVM. PAVMs are associated with intracranial abscesses due to shunting and loss of the normal filtering effects of the lung capillary bed. Impaired pulmonary filtration can permit paradoxical thromboemboli and septic microemboli to enter systemic circulation, predisposing patients with PAVMs to cerebral abscess and ischemic stroke. Screening for PAVMs with contrast enhanced echocardiogram or enhanced CT chest may be considered in patients with cryptogenic brain abscess or recurrent embolic stroke of unknown origin. PAVMs are often associated with hereditary hemorrhagic telangiectasia (HHT). As many features of HHT have delayed clinical manifestation, genetic testing for HHT should be considered in patients with PAVM, even in the absence of other clinical features. In our case, genetic testing returned positive, confirming a new diagnosis of HHT type 1.

Complex, Isolated Pulmonary Arteriovenous Malformation in Two Children With Severe Cyanosis.

We present two cases of Isolated complex pulmonary arteriovenous malformations in two children presenting with cyanosis and exercise intolerance. We present the anatomical features and the management of each case. One patient was treated with surgical ligation of the draining vein, and one patient was treated percutaneously by closure of the feeding segmental artery.

Pulmonary Arteriovenous Malformation in Combination With Stroke.

BackgroundAs pulmonary arteriovenous malformation (PAVM) include a right-to-left shunt, it can be accompanied by fatal complications such as stroke and brain abscess due to paradoxical embolism. There are few PAVM patients accompanied by concurrent pulmonary embolism, so the treatment sequence has not been established. Case presentationA 62-year-old female patient was transferred to our hospital with a simple PAVM and concurrent bilateral pulmonary embolism (PE). The acute thromboembolus was extended to the proximal segmental artery where the feeding artery originated. Anticoagulation was started, but on the fifth day of admission, the patient complained of left side weakness and brain magnetic resonance imaging revealed an acute infarction in the right lateral thalamus. This situation could lead to a dilemma between the risk of thrombus migration during catheter manipulation in PAVM embolization and another embolic event due to the late occlusion of the shunt during anticoagulation. This complex situation was successfully managed with delayed endovascular embolization for PAVM after four months of anticoagulation. The cause of PE in this patient was eventually diagnosed as antiphospholipid syndrome (APS).ConclusionThe authors reported a rare case of APS-induced PE in the PAVM feeding artery course that led to stroke during hospitalization. We successfully treated this patient with delayed endovascular embolization for PAVM after anticoagulation for PE and stroke. It is thought to be valuable in deciding for a treatment plan for this rare condition.

Idiopathic Pulmonary Arteriovenous Malformation - A Rare Entity

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.

Ultra-short echo time magnetic resonance angiography using a modified signal targeting with alternative radio frequency spin labeling technique for detecting recanalized pulmonary arteriovenous malformation after coil embolization

Pulmonary arteriovenous malformation (PAVM) is a rare vascular anomaly, for which transcatheter embolization with metallic coils is the standard of care. Although detecting recanalization after embolotherapy is crucial, direct visualization of residual flow with computed tomography or magnetic resonance (MR) imaging is generally difficult due to metal artifacts. We present a case of recanalized PAVM after coil embolization detected by ultra-short echo time MR angiography using a modified signal targeting with an alternative radio frequency spin labeling technique.