Alternative approach for right ventricular failure after left ventricular assist device placement in animal model

Abstract

Objectives: Right ventricular failure after left ventricular assist device (LVAD) implantation is associated with high mortality. This study was designed to evaluate the effectiveness of an atrial septostomy with a membrane oxygenator incorporated in an LVAD as a novel approach for right ventricular failure after LVAD implantation.

Methods: The outflow and inflow cannulae were placed in the carotid artery and left ventricular apex, respectively. A centrifugal pump and an oxygenator were sequentially placed between the inflow and outflow cannulae in seven anesthetized goats. While right ventricular failure was induced by pulmonary artery banding, a balloon atrial septostomy was performed using a 19-mm balloon catheter under echocardiographic guidance. We investigated the effects of the interatrial shunt on LVAD flow and haemodynamics.

Results: Development of right ventricular failure decreased LVAD flow (2.7 ± 0.6-0.9 ± 0.6 l/min), causing a state of shock [mean arterial pressure (MAP) of 41 ± 12 mmHg]. Following a balloon atrial septostomy, LVAD flow and MAP were significantly improved to 2.7 ± 0.4 l/min (P < 0.001) and 53 ± 18 mmHg (P = 0.006), respectively, while right atrial pressure decreased from 18 ± 5 to 15 ± 5 mmHg (P = 0.001). Furthermore, arterial blood oxygenation was maintained by the membrane oxygenator incorporated in the LVAD.

Conclusions: In the present model of right ventricular failure after LVAD implantation, LVAD flow was significantly increased and haemodynamics improved without compromising systemic oxygenation by the use of an interatrial shunt and a membrane oxygenator incorporated in the LVAD. Our results indicate that this novel approach may be less invasive for a right ventricular failure after LVAD implantation.

Keywords: Animal model; Circulatory assist device; Heart failure; extracorporeal membrane oxygenation.