Minimally invasive insertion of an equine stented pulmonary valve with a built-in sinus portion in a sheep model

OBJECTIVES: This study evaluated the feasibility of inserting a new equine stented-valve with a sinus portion in a lamb survival model, through a minimally invasive thoracotomy with right ventricular access without cardiopulmonary bypass.

BACKGROUND: Extant surgical or percutaneous methods for inserting biological valves in the right outflow tract have drawbacks and limitations.

METHODS: A decellularized equine valved jugular vein, sutured to a self-expanding stent with a sinus portion, was placed through a minimal right thoracotomy using a newly developed flexible hydraulic release device in seven lambs. The approach through the right ventricle into the pulmonary valve position is achieved on a beating heart.

RESULTS: The stented valves were correctly positioned in the right outflow tract, were competent up to 6 months as confirmed by angiography and echocardiography, and were well-tolerated by the animals, with endothelialization of the valve demonstrated at 6 months.

CONCLUSIONS: The newly developed hydraulic release system allowed for safe and reliable insertion of an equine stented-valve with a sinus portion, through a right transventricular approach on a beating heart, in a sheep survival model.