Imaging findings and complications of transcatheter interventional treatments via the inferior phrenic arteries in patients with hepatocellular carcinoma

OBJECTIVE: To evaluate imaging findings and complications from transcatheter interventional treatment of hepatocellular carcinoma via the inferior phrenic arteries. MATERIAL & METHODS: 40 procedures in 25 patients (19 men; age range, 57–89 years) were retrospectively reviewed in this study. In all procedures, a micro-catheter was selectively inserted in the right inferior phrenic artery (n = 39) or left inferior phrenic artery (n = 1), and transcatheter arterial chemoembolization (n = 39) or transcatheter arterial embolization (n = 1) was performed. Imaging findings and patient charts were reviewed, and complications until time of discharge (median hospitalization period, 10.5 days; range, 3–21) were assessed. RESULTS: On angiography or computed tomography during angiography, collateral circulation from the right inferior phrenic artery to the pulmonary artery was seen in eight of 39 procedures (seven patients, 28%). In seven of these procedures, Lipiodol deposition was seen on the unenhanced computed tomography just after the procedure (post-procedure computed tomography) in the pulmonary arteries or pleura, and in six procedures, the deposited Lipiodol was noted to have spread into adjacent lung fields on the one week follow-up computed tomography. Branches of the right inferior phrenic artery were seen along the right margin of the heart in 18 procedures, and Lipiodol deposition was seen along the right margin of the heart on post-procedure computed tomography in four procedures. Complications occurred in 21 of 39 procedures of right inferior phrenic artery intervention (53%): shoulder pain in 18 (45%), pleural effusion in 14 (35%), basal atelectasis in 11 (28%), paroxysmal atrial fibrillation in two (5%) and hemoptysis in one (3%). In 14 procedures (35.9%), pleural effusion was seen on follow-up computed tomography examinations, and 11 (28.2%) of these procedures also showed basal atelectasis. However, only three procedures with pleural effusion showed Lipiodol deposition on the post-procedure computed tomography. In one patient who underwent transcatheter arterial chemoembolization twice via the right inferior phrenic artery, atrial fibrillation occurred after both procedures. CONCLUSIONS: Transcatheter arterial chemoembolization or transcatheter arterial embolization via the inferior phrenic artery in patients with hepatocellular carcinoma was relatively safe. Shoulder pain was the most frequent complication, and required only conservative treatment. There was no clear connection between pleural effusion or basal atelectasis and collateral circulation from the right inferior phrenic artery to the pulmonary artery depicted on angiography, computed tomography during angiography or post-procedure computed tomography.