Transvenous Retrograde Thoracic Duct Cannulation in a Porcine Model: A Technical Note on Initial Feasibility

Thoracic duct embolization (TDE) is a valuable minimally invasive treatment for chylous leaks. Pre-clinical evaluation of emerging embolic materials in appropriate animal models is crucial. This study aimed to establish and assess the technical feasibility of transvenous retrograde thoracic duct cannulation, a key component for TDE, in a porcine model.

This prospective feasibility study, with institutional animal care committee approval, used five healthy female Large White pigs (mean weight, 50.2 ± 8.9 kg). Under general anesthesia, interstitial lymphangiography of the left forelimb with Lipiodol was performed for guiding transvenous retrograde cannulation. Following percutaneous femoral vein access, retrograde thoracic duct cannulation was attempted using an angiographic catheter and microcatheter assembly. Post-mortem necropsy examined the thoracic duct junction anatomy.

Interstitial lymphangiography visualized the thoracic duct terminus in three pigs. Selective venography consistently demonstrated the thoracic duct ampulla converging at the junction of the left internal and external jugular veins. The angiographic catheter successfully engaged the thoracic duct ampulla in all five cases. Subsequent microcatheter cannulation of the thoracic duct was achieved in three of five pigs. Necropsy confirmed the thoracic duct ampulla's location between and caudal to the junction of the left internal and external jugular veins.

Transvenous retrograde cannulation of the thoracic duct is technically feasible in the porcine model, offering a platform for pre-clinical TDE research. Technical refinements are warranted to improve success rates.