AvalonElite Double Lumen Cannula for Total Cavopulmonary Assist in Failing Fontan Sheep Model with Valved Extracardiac Conduit.

ABSTRACT

The AvalonElite double lumen cannula (DLC) provides total cavopulmonary assist (CPA) in failing Fontan sheep, but recirculation limits reliability. To improve CPA performance, a two-valve extracardiac conduit (ECC) was used to bracket infusion blood toward pulmonary artery (PA). A total cavopulmonary connection with failing Fontan circulation adult sheep model was created with valved ECC (n = 6). The valved ECC was connected to superior/inferior venae cavae (SVC/IVC) and right PA. The AvalonElite DLC was inserted from right jugular vein with infusion opening between the ECC valves. The DLC drainage lumen withdrew blood from SVC/IVC, and the infusion lumen returned blood to ECC. A failing Fontan sheep model with valved ECC was successfully created. Central venous pressure increased from 9 ± 1 to 17 ± 1 mm Hg, systolic arterial pressure decreased from 103 ± 9 to 51 ± 13 mm Hg, and cardiac output decreased from 3.6 ± 0.3 to 1.4 ± 0.2 L/min. Serum lactate significantly increased, indicating poor tissue perfusion. At 4 L/min pumping flow, the AvalonElite DLC returned hemodynamics/lactate to baseline levels throughout 6 hour CPA. Necropsy revealed intact/well-functioning ECC valves and well-positioned DLC with no visible thrombosis. The AvalonElite DLC provides reliable CPA performance in failing Fontan sheep with valved ECC.