Percutaneous temporary aortic valve: a proof-of-concept animal model

An early prototype of a temporary aortic valve (TAV) catheter system was evaluated for its potential to serve as an integrated device for aortic valve intervention and replacement. The prototype consisted of two essential components: a central catheter for the delivery of aortic valve interventional tools (valve debulking, resection, replacement); and a balloon-inflatable temporary valve for hemodynamic support when the native aortic valve is removed. After valve replacement, the TAV catheter system is designed to be readily withdrawn from the subject.

Individual aspects of both components of the prototype were examined in experiments with four pigs. The central catheter was used to deliver a self-expanding stent for native aortic valve ablation to create acute severe aortic insufficiency (AI). The balloon-TAV was deployed in the proximal aorta to control the induced AI. Electrocardiographic (ECG), cardiac output (CO), pulmonary wedge pressure (PWP), left ventricular (LV) pressure, and aortic pressure proximal and distal from the TAV were recorded.

The central catheter was successful in delivering and deploying the valve ablation stent at the annulus to create massive AI; the LV diastolic pressure was increased from 12.6 +/- 1.1 to 32.4 +/- 2.0 mmHg (p < 0.001) with valve ablation. The deployed TAV in the proximal aorta led to a re-narrowing of the distal pulse pressure with a drop in the LV diastolic pressure to 21.5 +/- 1.5 mmHg (p < 0.001). During TAV support, some PWP lowering and a CO rise occurred, but these did not achieve statistical significance; no significant acute ECG changes were noted.

In this early prototype, the TAV catheter system demonstrated the potential to serve as an integrated device for both aortic valve modification and replacement.