Transcatheter Proximal Coil Blocking with n-Butyl-2-Cyanoacrylate Injection via the Pulmonary Artery Alone for Rasmussen’s Aneurysm

Case Reports in Radiology
19 Apr, 2019 ,

 A 51-year-old man came with Rasmussen’s aneurysm that was successfully treated by proximal coil blocking with n-butyl-2-cyanoacrylate (NBCA) injection via the pulmonary artery alone. With proximal coil blocking, a sufficient amount of NBCA could be injected without unintended reflux of the NBCA cast to the proximal pulmonary artery. 

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A 51-year-old man was referred to our hospital for treatment of hemoptysis. One week before, he presented with coughing up of approximately 1 cup of bright red blood, which was diagnosed as active pulmonary tuberculosis. He had poorly controlled diabetes mellitus.

When he arrived at our hospital, hemodynamic status was stable, and there were no abnormal signs or symptoms, except for low-grade fever and mildly elevated C-reactive protein. Contrast-enhanced computed tomography (CT) revealed a 7 mm round pseudoaneurysm within a cavitary lesion in the left upper lobe of the lung. The pseudoaneurysm was thought to originate from a branch of the left superior segmental pulmonary artery. He was diagnosed with Rasmussen’s aneurysm and underwent interventional treatment.

A 5-Fr catheter (SHK, Terumo Clinical Supply, Gifu, Japan) was advanced to the left bronchial artery. A left bronchial angiography depicted the aneurysm via a shunt from the bronchial to the pulmonary artery. However, we could not advance the microcatheter to a more peripheral branch near the lesion, because the anastomosis was small and tortuous. Eventually, subintimal dissection developed in the left bronchial artery and we failed to embolize the aneurysm via the left bronchial artery.

Subsequently, a 5-Fr guiding catheter (Envoy, Codman Neurovascular, Raynham, Massachusetts, USA) was advanced to the left main pulmonary artery. Left main and left superior segmental pulmonary angiography could not depict the aneurysm. However, we noted an abrupt disappearance of the left superior segmental pulmonary artery, which indicated retrograde flow from the bronchial to the pulmonary artery. The tapering was in the branch that was suspected as the parent artery of the aneurysm on CT. Based on these findings, we were able to identify the parent artery and reach the aneurysm using the microcatheter.

Two microcatheters were placed in the aneurysm and pulmonary artery proximal to the aneurysm. A 1.7-Fr microcatheter (Echelon, ev3, Irvine, California, USA) and a 1.9-Fr microcatheter (Carnelian Marvel, Tokai Medical Products, Aichi, Japan) were inserted in parallel through a guiding catheter. The 1.7-Fr microcatheter was positioned proximal to the aneurysm, whereas the 1.9-Fr microcatheter was advanced into the aneurysm.

Because we decided to choose NBCA for embolization, we first performed proximal superior segmental pulmonary artery embolization proximal to the aneurysm using the 1.7-Fr microcatheter, with 3 coils measuring 3 mm × 6 cm, 2.5 mm × 6 cm, and 2 mm × 8 cm (ED COIL10 ExtraSoft Type R, Kaneka Medix, Osaka, Japan) to prevent unintended reflux of the NBCA.

Thereafter, a 0.8 mL mixture of NBCA and iodized oil (Lipiodol, Guerbet Japan, Tokyo, Japan) (NBCA:Lipiodol = 1:3) was retrogradely injected into the aneurysm through the remaining 1.9-Fr microcatheter. The aneurysm was filled with the mixture of the NBCA and iodized oil, but the feeding artery could not be embolized retrogradely.  

Although postembolization bronchial angiography could not be performed due to the subintimal injury in the left bronchial artery, postembolization pulmonary angiography did not show the residual aneurysm.

After treatment, he remained stable without further hemoptysis, and there were no other side effects or complications. Follow-up CT performed 2 months later confirmed successful embolization of the aneurysm.