Pulmonary Arteriovenous Fistula:A Case Report And Review Of The Literture

Objective:Pulmonary arteriovenous fistula is a rare disease with atypical symptoms that can be easily misdiagnosed.This paper aims to improve the understanding of the clinical manifestations,diagnosis,differential diagnosis,treatment of pulmonary arteriovenous fistula by literature review and a case report.Materials and methods:To report a clinic case from Department of thoracic surgery of Qilu Hospital of Shandong University about pulmonary arteriovenous fistula,and to study case reports included in CNKI,then to give a literature review.Result:Pulmonary arteriovenous fistula is a rare disease in clinic,the etiology is that pulmonary vessels expand and come into the formation of cavernous hemangioma,one or more pulmonary arteries directly connect with veins without capillaries.Clinical symptoms are due to shunt or rupture of blood vessels.According to the causes it can be divided into primary arteriovenous fistula and acquired pulmonary arteriovenous fistula.The former one may be associated with congenital artery malformations.,especially HHT;the latter can be caused by trauma,tumor,inflammation,degenerations etc..The disease can occur in all parts of the lung,but the most in the right lower lobe.Pulmonary arteriovenous fistula clinical symptoms mainly depends on the degree of shunt fistula,lacking of specific clinical symptoms.Some may have no symptoms,while the most common clinical manifestations were exertional dyspnea and cyanopathy.The disease can be misdiagnosed as other pulmonary diseases,such as tuberculosis,bronchiectasis,lung cancer and lung metastasis due to symptoms such as hemoptysis,hematemesis,syncope,cerebral embolism and so on.Patients with a longer history and symptoms such as severe illness,cyanosis acropachy may be misdiagnosed as cyanotic congenital heart disease.Imaging examination includes X-ray,CTA,DSA,MRI,etc...X-ray can be used as a simple screening method.CT,especially multi-slice spiral CT,can significantly improve the detection rate of small lesions.DSA can clearly and completely show the presence of shunt pulmonary arteriovenous vascular structure,and its location,shape,extent diameter and flow size,is the gold standard for diagnosis of pulmonary arteriovenous fistula.If the treatment is not timely,it can lead to structure changes of the heart and lung,so as to worsen the prognosis.Current treatments include surgery and interventional therapy.Surgical excision is a type of radical treatment.Severe pulmonary arteriovenous fistula is an indication of bilateral lung transplantation.Interventional therapy is a non-surgical treatment as a new method developed in recent years.By the means of intervention embolization technology,it leads to less trauma and faster recovery.One advantage is that it can be used in patients cannot or unwilling to accept surgery,such as patients with congenital heart disease.But operators' experience,skills,equipment requirement is essential.Conclusion:Pulmonary arteriovenous fistula is rare in clinic,and it is usually manifested by hypoxia,pulmonary infection,hemoptysis and other atypical symptoms.For those who have the above symptoms,chest X-ray examination can be first screening,and CTA can be used to avoid misdiagnosis.Treatment can be chosen according to the patient' basic situation.