Smoking Significantly Impacts Persistence Rates in Embolized Pulmonary Arteriovenous Malformations in Patients with Hereditary Hemorrhagic Telangiectasia

Correlation between pre-operative VE-cadherin and DLL4 and the maturation after primary arteriovenous fistula in uremic patients

Aims

Uremic patients require dialysis to replace the declined kidney function, and arteriovenous fistula (AVF) is a commonly used dialysis access route. Our study aimed to explore vascular endothelial cells cadherin (VE-cadherin) and Delta-like ligand 4 (DLL4) expression in uremic patients undergoing primary AVF surgery and their correlation with AVF maturation.

Methods

We conducted a prospective study that included n = 55 voluntary uremic patients receiving their initial AVF procedure for renal replacement therapy, subjects were divided into a mature group and a failure group based on whether the AVF matured within 3 months post-operatively. We analyzed the association of VE-cadherin and DLL4 with AVF maturation by examining their expression levels in serum and the endothelium of cephalic veins.

Results

Pre-operative serum VE-cadherin, in the mature group measured 125.07 (106.77-167.65) ng/L, and DLL4 was 92.78 (83.83-106.72) pg/mL, while the failure group had VE-cadherin at 95.40 (79.03-107.16) ng/L (P = 0.001), and DLL4 at 60.42 (43.98-80.15) pg/mL with a statistical significant; (P = 0.002), binary logistic regression analysis indicated a significant association between cephalic vein diameter, VE-cadherin, DLL4 levels, and AVF immaturity (P = 0.024, P = 0.014 respectively). Immunohistochemical staining showed slightly higher VE-cadherin levels in the mature group than in the failure group (P = 0.366). DLL4 was primarily located in the cell membrane and cytoplasm, concentrated in the inner membrane, with significantly higher levels in the mature group compared to the failure group (P = 0.027).

Conclusion

The failure group exhibited lower levels of VE-cadherin and DLL4 in serum and vascular tissue, these results suggest that VE-cadherin and DLL4 might play pivotal regulatory roles in the onset and the progression of fistula immaturity, potentially serving as promising targets for future interventions.

Transarterial Embolization of Simple Pulmonary Arteriovenous Malformations: Long-Term Outcomes of 0.018-Inch Coils versus Vascular Plugs

PURPOSE

To compare the safety, effectiveness, and persistence rates of 0.018-inch coils with those of Amplatzer vascular plugs (AVPs; Abbott Vascular, Abbott Park, Illinois) for the treatment of pulmonary arteriovenous malformations (PAVMs) in response to a growing concern that 0.018-inch coil embolization would increase the long-term persistence rate.

MATERIALS AND METHODS

This is a retrospective, single-center study of a database (2002-2020) of 633 PAVM embolizations. Complex PAVMs and those not embolized with 0.018-inch coils or plugs were excluded. PAVM embolization material was classified into 4 groups: (a) 0.018-inch nonfibered coils (NFCs), (b) 0.018-inch fibered coils (FCs), (c) NFCs and FCs, or (d) plugs. Persistence was defined as flow through the PAVM on digital subtraction angiography (DSA) or as <30% diameter reduction of the aneurysmal sac on unenhanced computed tomography (CT). Kaplan-Meier analysis and Cox regression were used to assess PAVM's persistence-free survival.

RESULTS

A total of 312 PAVM embolizations with NFCs (43 PAVMs), FCs (127 PAVMs), NFCs and FCs (12 PAVMs), or plugs (130 PAVMs) in 109 patients (28% men; mean age = 49 years) were included. All PAVM embolizations were technically successful without any major adverse events. PAVM persistence-free survival rates at 10 years' follow-up were 40.8% versus 44.7% in the NFC and FC groups (P = .22) and 47.3% versus 81.0% in the 0.018-inch coil (NFC or FC) and plug groups (P < .0001), respectively. There were 0.43 (79/182) and 0.08 (10/130) re-embolization procedures per PAVM in the 0.018-inch coil and plug groups, respectively (P < .001).

CONCLUSIONS

PAVM embolization with 0.018-inch coils was safe, but persistence rate with PAVM embolization was significantly higher than that with plugs, with no significant differences between FCs and NFCs.

Diagnosis and endovascular management of pulmonary arteriovenous malformations

Pulmonary arteriovenous malformations (PAVM) are abnormal communication of a branch of the pulmonary artery and pulmonary vein circumventing the intervening pulmonary capillaries. This results in a right-to-left (R-L) shunt and its related manifestations, which include hampered gas exchange leading to hypoxaemia, dyspnoea, paradoxical emboli leading to stroke, cerebral abscess, myocardial infarction and pulmonary haemorrhage due to rupture of the PAVM. Endovascular transcatheter embolization of the feeding vessels with coils or occlusion devices is the current standard care of treatment and preferred treatment modality. The articles aim to provide insights into the current trends in diagnosis, the current recommendations, approach and management options for patients with PAVM.

Arteriovenous Malformations in the Setting of Osler-Weber-Rendu: What the Radiologist Needs to Know

Osler-Weber-Rendu, also known as Hereditary Hemorrhagic Telangiectasia, is an autosomal dominant disease with phenotypic manifestations that include pulmonary, cerebrospinal, hepatic, and other visceral arteriovenous malformations (AVMs). Pulmonary AVMs can result in hypoxemia, hemoptysis, or stroke due to paradoxical embolism. The mainstay of treatment is transcatheter embolization. Central nervous system and abdominal visceral AVMs contribute to morbidity of the disease. Radiologists should be familiar with the imaging manifestations and treatment algorithm of AVMs in Osler-Weber-Rendu to effectively guide patient care.

Idiopathic and hereditary haemorrhagic telangiectasia associated pulmonary arteriovenous malformations: comparison of clinical and radiographic characteristics

AIM

To determine whether there are differences between idiopathic and hereditary haemorrhagic telangiectasia (HHT) associated pulmonary arteriovenous malformations (PAVMs) (HHT-PAVM) regarding clinical and radiographic characteristics, and the results of embolotherapy.

MATERIALS AND METHODS

A retrospective analysis was undertaken of all adult and adolescent patients who were diagnosed with a PAVM on chest computed tomography (CT) from January 2006 until August 2019.

RESULTS

In total, 41 patients with idiopathic PAVMs and 194 patients with genetically confirmed HHT and PAVMs were included. Idiopathic PAVMs were more frequently observed in female patients, were more solitary, and predominantly located in the lower lobes. The diameter of the feeding artery and type of PAVM (simple versus complex) were similar. Embolotherapy results were comparable between both groups with similar re-embolisation rates.

CONCLUSIONS

PAVMs of idiopathic origin are predominantly found in women, more frequently located in the lower lobes, and solitary compared to HHT-PAVMs; however, the outcome of treatment is the same, suggesting that treatment and follow-up should be similar in both groups.

Approach to Pulmonary Arteriovenous Malformations: A Comprehensive Update

Pulmonary arteriovenous malformations (PAVMs) are abnormal direct vascular communications between pulmonary arteries and veins which create high-flow right-to-left shunts. They are most frequently congenital, usually in the setting of hereditary hemorrhagic telangiectasia (HHT). PAVMs may be asymptomatic or present with a wide variety of clinical manifestations such as dyspnea, hypoxemia, or chest pain. Even when asymptomatic, presence of PAVMs increases patients' risk of serious, potentially preventable complications including stroke or brain abscess. Transcatheter embolotherapy is considered the gold standard for treatment of PAVMs. Though previous guidelines have been published regarding the management of PAVMs, several aspects of PAVM screening and management remain debated among the experts, suggesting the need for thorough reexamination of the current literature. The authors of this review present an updated approach to the diagnostic workup and management of PAVMs, with an emphasis on areas of controversy, based on the latest literature and our institutional experience.