A rare case of pulmonary artery to left atrium fistula

Abstract

Abstract Background The first description of right pulmonary artery-to left atrium communication was done by Friedlich and coauthors in 1950. The right pulmonary artery and left atrium are directly connected by the right pulmonary artery to left atrial fistula through a thin-walled aneurysm. Here, we describe a female adult patient who underwent investigation for dyspnea and had Type 1 right pulmonary artery to left atrium connection. Case presentation Twenty-two-year-old female presented with history of breathlessness (New York Heart association classification grade III) for 3 years. On initial examination, her saturation was 60% with no clinical evidence of cyanosis. Initial radiographic examination and CT pulmonary angiogram revealed a dilated communication between the right inferior pulmonary artery and left atrium. The patient was then referred for cardiac MRI. The MR imaging showed the following findings: Dilated right ventricle and atrium with Ostium secundum type of atrial septal defect. Large focal outpouching was noted arising from the right inferior pulmonary artery whose inferomedial portion appeared to communicate with left atrium. The final diagnosis was right pulmonary artery to left atrial fistula-Type I with ostium secundum type atrial septal defect. Midline sternotomy was performed for ligation of this fistula with septal correction. Post surgery, patient began to improve clinically and her saturation in room air increased to 92% Conclusions Right pulmonary artery to left atrial fistula is different from the pulmonary AV fistula and its rarity directs the need for imaging to diagnose the condition and for management selection. The fistulous connection, which most frequently originates from the posterior wall of the descending branch of RPA and inserts into the LA, is readily seen on CT/catheter angiography. Due to the rarity of this entity and much fewer evidences in imaging, we have reported a type 1 right pulmonary artery to left atrium connection.

Keywords

• Right pulmonary artery-to left atrium communication
• Atrial septal defect
• CT angiography