Abstract 16981: Mechanical Circulatory Support by Impella Improved Failing Single Ventricle Physiology in Pigs
Background: There are a growing failing classic Fontan population in adolescents and adults. We tested a novel micro-axial pump (Impella 5.0) to support the failed Fontan circulation in a pig model.
Methods: The Fontan model was established in juvenile pigs by connecting right atrium to main pulmonary artery, tricuspid valve destruction. The Impella catheter was inserted from distal main pulmonary artery to right atrium (Figure 1 ). The pig was put on pure Fontan physiology without Impella support for 10 min, then Impella assistance began. Hemodynamics, blood gas analysis and echocardiogram data were compared at baseline (T0), Fontan without Impella assistance (T1), 1h, 3h, 6h, 12h (T2, T3, T4, T5) post Fontan with Impella assistance.
Results: Seven pigs successfully underwent Fontan completion. Four of them survived over 12 hours after operation, and one survived 6 hours. Two pigs died within 3 hours from device malfunction. Mean arterial pressure significantly decreased on T1 when compared to T0 (25.6±2.6 vs 58.1±5.3 mmHg, P<0.01), and it increased after Impella assistance (39.6±7.8, 39.7±10.9, 39±7.4, 31.3±5.1 mmHg at T2, T3, T4, T5, P<0.01). Central venous pressure was significantly high on T1 compared to baseline (2.9±1.1 vs 13.4±1.1, P<0.01), and effectively low on T2-T5 (5±2.6, 3.5±1.8, 3.8±2.2, 3.3±2.6, P<0.01). Mean mixed venous saturation decreased from 71.1±11.6% at T0 to 23.6±9.3% at T1 (P<0.01), while Impella assistance normalized it to baseline value gradually (P<0.01). Echocardiogram exam revealed that cardiac output and stroke volume significantly decreased when on pure Fontan circulation compared to baseline, while they were remarkably improved by Impella assistance (P<0.01).
Conclusions: The pigs with classic Fontan circulation hardly survived without Impella assistance, which indicates failing Fontan physiology. Impella assistance improved hemodynamics, normalized systemic perfusion, and maintained sufficient cardiac output.
- © 2013 by American Heart Association, Inc.