Introduction
Pulmonary arteriovenous malformation (AVM) is a rare abnormality of the blood vessels in the lungs. It is a problem in which there are abnormal communications between a pulmonary artery and a pulmonary vein. This causes irregularity in the regular gas exchange and filtration of blood.
Aetiology
It can either be congenital or acquired. Usually, congenital cases are secondary to Hereditary Haemorrhagic Telangiectasia.
Acquired causes include prior chest surgery, injury, infections such as schistosomiasis and actinomycosis, heart condition like Mitral stenosis. Rare conditions such as Fanconi's syndrome, hepatic cirrhosis related hepatopulmonary syndrome, and metastatic carcinoma are also acquired.
Pulmonary AV malformations can be present from birth and develop in adulthood. Many individuals with Pulmonary AV Malformations will later develop Hereditary Hemorrhagic Telangiectasia
Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder characterised by multiple arteriovenous malformations (AVMs) that lack intervening capillaries and result in direct connections between arteries and veins.
The most common clinical manifestation is spontaneous and recurrent nosebleeds, beginning on average at the age of 12 years. Telangiectasis (minor AV Malformations) is characteristically found on the lips, tongue, buccal and gastrointestinal mucosa, face and fingers.
Presentation
Most patients are asymptomatic. The majority of cases often develop by the fourth and sixth decades of life. However, patients with hereditary hemorrhagic telangiectasia develop symptoms by the second decade of life.
However, it can also present with the following symptoms:
- Breathlessness on exertion
- Cough
- Blood-stained sputum
- Bleeding from nose
- Chest pain
- Palpitations
- Shortness of breath
Investigations
Diagnosis of pulmonary AV malformations is as follows:
- Chest X-ray
- Contrast-enhanced CT scan
- MRI with or without MR angiogram
- Radionuclide lung scan
- Pulmonary angiography
- Transthoracic contrast Echocardiogram (TTCE)
Pulmonary AVM Symptoms
Let’s discuss pulmonary AVM symptoms. There are many Pulmonary AVM symptoms. Here are the symptoms of pulmonary arteriovenous malformations (PAVMs):
- Shortness of breath particularly when upright or during exertion.
- Bleeding is coughing blood around the lungs.
- Decreased oxygen level
- Weak artery and vein walls,
- Clots or bacteria in the lung circulation
- Chest pain
- Other symptoms like cough, clubbing, dysarthria, syncope, vertigo, cyanosis, migraine headaches, murmurs, bruits, tinnitus, dizziness, and diplopia.
Pulmonary AVM Causes
Let’s discuss Pulmonary AVM causes. Here are the factors that cause Pulmonary AVM.
- Congenital heart disease
- Mutations
- Chronic infections
- Trauma
- Liver cirrhosis
Pulmonary Arteriovenous Malformation Diagnosis
A combination of noninvasive methods, imaging studies, and other tests can be used to diagnose pulmonary arteriovenous malformation (PAVM). A few of the tests that are used to diagnose a PAVM include :
- Bubble study: In this method, the bubbles will go through the AVM and could be detected by the ultrasound.
- CT angiography: It helps measure and enumerate the lung AVMs.
- Pulmonary angiography: It helps to look into and treat abnormal blood vessels.
- Contrast-enhanced echocardiography: Helps confirm the presence of a right-to-left shunt.
- Radionuclide perfusion lung scanning: Helps confirm the presence of a right-to-left shunt.
Treatment of Pulmonary AV Malformations
Definite treatment for pulmonary arteriovenous malformations (PAVM) involves therapeutic embolisation or surgical resection. Therapeutic embolisation includes angiographic embolisation with a metal coil or balloon occlusion.
Conclusion
Though the patients present asymptomatically and the findings are incidental, the condition may be life-threatening. Adequate treatment availability and technological advancement play a significant role in bringing the individual back to normalcy.
FAQs
1) How serious is a pulmonary avm?
Pulmonary arteriovenous malformations (PAVMs) could become serious and life-threatening, but detecting it early and providing treatment could help improve outcomes.
2) What is the aim of Pulmonary AVM Radiology?
Pulmonary AVM Radiology will help find out the patients at risk for pulmonary arteriovenous malformation (PAVM) by understanding symptoms like dyspnea, hypoxemia, and exercise intolerance.
3) What is Pulmonary AVM embolization?
Pulmonary AVM embolization refers to a minimally invasive method that helps treat the abnormal connections between the pulmonary artery and vein in the lungs.
4) What is the purpose of AVM lung surgery?
The aim of AVM surgeries, including AVM lung surgery, is to help prevent bleeding by clearing off or lowering the tangled blood vessels. This will permit blood to flow normally through the capillaries.
