Discussion
A fragmented central venous portal catheter with distal segment embolisation is a rare but well-documented complication, and may pose difficulties during retrieval. The true incidence rate of the fractured portal catheter is unknown and may range from 0.5-1% [1]. The most frequent fractured site of the catheter is at the anastomosis between injection port and catheter [2]. The most common location of a distal segment embolisation is between the superior vena cava and right atrium. Besides, migration to the right ventricle or pulmonary artery is occasionally found. A percutaneous transvenous retrieval technique should be tried first because it is feasible, less invasive and less risky, although some unusual complications have been reported in the real world [3].
Most of the fragmented catheter can be removed successfully via transfemoral access. Other access sites such as the internal jugular venous approach have been reported. As for the distal segment migration into the coronary sinus, there is only one reported case thus far and it was successfully retrieved from right basilar vein access via the loop-snare technique [4].Catheter migration into the middle cardiac vein has yet to be reported in the literature. In this case, we first approached from the right femoral venous route because the inferior vena cava (IVC) is large enough to have most loop-snares inserted, and quite safe during manipulation of the device. However, this access failed due to the broken tip being pointed cranially and because there was a sharp angle between the loop snare and the proximal fractured segment. The orifice of the coronary sinus is situated along the inferomedial surface of the right atrium, and the curve of the lumen points cranially toward the superior vena cava and the internal jugular vein. Hence it is extremely difficult to retrieve the fragmented catheter from the IVC access. On the contrary, the transjugular venous approach would be technically easier because the alignment between the fractured catheter and lasso is more coaxial.
In conclusion, once it is highly suspected that the broken port catheter has migrated into the coronary sinus, a CT is strongly recommended as a tool to define the location of the fragmented catheter, and transjugular venous retrieval is a feasible and effective approach.