Pulmonary arterio-venous malformation: a catastrophe

Pulmonary Arteriovenous Malformations (PAVM) are abnormal fistulous connections between a pulmonary artery and a pulmonary vein that generate a right-to-left shunt by avoiding the normal pulmonary capillary bed. We report an unusual case of a young female patient who presented to the department of Obstetrics and Gynaecology with Bleeding per vagina diagnosed as Failed intrauterine pregnancy; Unilateral pedal edema and Breathlessness. Pulmonary Thromboembolism was suspected and Computed Tomography pulmonary angiogram (CTPA) was advised for, which showed abnormal communication between dilated left main pulmonary artery and dilated tortuous superior pulmonary vein. Multiple adjacent solid and ground glass nodules were also noticed which were suggestive of initial telangiectatic state of PAVMs. Most of PAVMs are related to Hereditary Hemorrhagic Telangiectasia, whereas only 10 to 20% are isolated sporadic cases. Pregnancy has been considered as a precipitant factor for PAVMs in most of the cases, patients and pregnant women affected by PAVMs are asymptomatic, but when the clinical manifestations occur, they are often related to the right-to-left shunting and may include dyspnoea, hypoxia, and pulmonary hypertension. Moreover, presence of one or multiple PAVMs during pregnancy is associated with an increased risk of severe complications such as rupture, haemothorax, and hypovolemic shock. Hence this case reports highlights the necessity for the radiologists to think in terms of PAVM as a differential diagnosis beyond the suspicion of Pulmonary thromboembolism to look for any abnormal arteria venous communication while reporting CTPA in pregnant women with breathlessness and foresee the catastrophic complications in an already known case of PAVM during pregnancy. Also, the radiologists should identify subtle solid or ground-glass nodules adjacent to large PAVMS which are the initial telangiectatic stage of PAVMs.