Massive pulmonary arteriovenous malformation presenting with tamponading haemothorax

Management of pulmonary arteriovenous malformations involves additional factors aside from the diameter of feeding arteries: a 3-year case-case retrospective analysis

Background

Pulmonary arteriovenous malformations (PAVMs) are rare but cause various manifestations. Although the diameter of feeding arteries has been linked to treatment decisions, relationships among the characteristics of PAVMs, clinical symptoms, and treatment effect remain unclear. The present study was performed to investigate how collective characteristics of PAVMs relate to clinical symptoms and to provide proper treatment recommendations for patients with PAVMs.

Methods

We retrospectively analysed 838,447 patients’ radiographic data and medical records from January 2018 to December 2020. Patients were included if a PAVM was radiographically detected for the first time in our hospital. Ordered multivariable logistic regression and hierarchical multiple regression were performed to analyse the relationships between characteristics of PAVMs and various clinical symptoms. We investigated the management of PAVMs in four tertiary university hospitals.

Results

Detection rate of PAVMs was 0.025% (207/838,447), and 37.6% of patients (78/207) also had hereditary haemorrhagic telangiectasia. Eight patients were diagnosed with bilateral diffuse PAVMs. Two hundred thirty-six lesions were detected in 199 patients, and the mean diameter of the feeding artery was 4.13 ± 1.92 mm. Most PAVMs were the simple type and located in the peripheral pulmonary area. In total, 34.3% of patients (71/207) were symptom-free; remaining patients showed various manifestations, and respiratory symptoms were most common (dyspnoea on exertion, 47.8%). The diameter of the feeding artery and the type and the number of PAVMs were correlated with hypoxaemia (P < 0.001, P < 0.001, and P = 0.037, respectively). The collective characteristics of PAVMs were not related to the severity of central nervous system symptoms (largest diameter of feeding artery, P = 0.8; largest diameter of sac, P = 0.42; number of PAVMs, P = 0.35; type of PAVMs, P = 0.99). Various symptoms were greatly relieved after treatment. The hospital investigation showed that management of PAVMs was not generally appreciated in clinical practice.

Conclusions

Our study revealed a low detection rate of PAVMs and a low degree of association with hereditary haemorrhagic telangiectasia in the general population. Considering the connection between collective characteristics of PAVMs and various clinical symptoms, clinicians should consider the type and number of PAVMs, the largest diameter of the feeding artery, and clinical symptoms when managing patients with PAVMs.

Iatrogenic pulmonary artery perforation associated with 5-Fr catheter manipulation during pulmonary arteriovenous malformation embolization with a vascular plug

Vascular plugs have been increasingly used because they have lower recanalization rates than coil embolization in pulmonary arteriovenous malformation (PAVM) embolization. To deliver the vascular plug close to the PAVM, a large-diameter catheter should be advanced into the feeding pulmonary artery, which carries a risk of vascular damage. Fifty-three-year-old women was admitted to our hospital for embolization of a single PAVM. Pulmonary angiography revealed a simple PAVM with a tortuous, small feeding artery in the right middle lobe, and feeding artery negotiation was attempted using a 5-Fr headhunter-type catheter to deliver the vascular plug. However, unintentional arterial perforation occurred suddenly when the guide wire was withdrawn after the catheter was advanced to the feeding artery adjacent to the sac. Immediate embolization using a vascular plug and microcoils at the proximal site of the perforation was performed to stop both PAVM shunt flow and bleeding. To prevent such a catheter-induced complication, it is necessary to select a diagnostic catheter with appropriate stiffness and angle and to switch to a small-diameter delivery system depending on the situation.

Massive haemorrhagic complications of ruptured pulmonary arteriovenous malformations: outcomes from a 12 years' retrospective study

Background

The life-threatening haemorrhagic complications of pulmonary arteriovenous malformations (PAVMs) are extremely rare, and only described in isolated cases. This study was designed to comprehensively investigate management of ruptured PAVMs.

Methods

We retrospectively assessed clinical and imaging data of ruptured PAVMs to summarize incidence, clinical characteristics, and outcomes following embolisation between January 2008 and January 2021.

Results

Eighteen of 406 (4.4%) patients with PAVMs developed haemorrhagic complications. Twelve of 18 patients were clinically diagnosed with hereditary haemorrhagic telangiectasia (HHT). Haemorrhagic complications occurred with no clear trigger in all cases. Eight of 18 patients (44.4%) were initially misdiagnosed or had undergone early ineffective treatment. 28 lesions were detected, with 89.3% of them located in peripheral lung. Computed tomography angiography (CTA) showed indirect signs to indicate ruptured PAVMs in all cases. Lower haemoglobin concentrations were associated with the diameter of afferent arteries in the ruptured lesions. Successful embolotherapy was achieved in all cases. After embolotherapy, arterial oxygen saturation improved and bleeding was controlled (P < 0.05). The mean follow-up time was 3.2 ± 2.5 years (range, 7 months to 10 years).

Conclusions

Life threatening haemorrhagic complications of PAVMs are rare, they usually occur without a trigger and can be easily misdiagnosed. HHT and larger size of afferent arteries are major risk factors of these complications. CTA is a useful tool for diagnosis and therapeutic guidance for ruptured PAVMs. Embolotherapy is an effective therapy for this life-threatening complication.

Hemothorax due to rupture of pulmonary arteriovenous malformation: an interventional emergency

Spontaneous hemothorax as a result of a ruptured pulmonary arteriovenous malformation (PAVM) is a life-threatening event and requires immediate interventional therapy. We present two patients who survived following emergent embolization. Definitive thoracentesis was delayed until embolization was performed. The tamponade provided by the hemothorax may have prevented exsanguination, suggesting to us that drainage of blood from the pleural space should be delayed until the PAVM has been treated. Hemorrhage from a PAVM may be the first manifestation of hereditary hemorrhagic telangiectasia. Genetic testing and screening for other family members should be considered.