The present disclosure relates generally to percutaneous heart pumps including a self-expandable and collapsible impeller housing fabricated from a mesh of a shape memory alloy, such as nitinol, and a base polymer coating and a top polymer coating. Specifically, the present disclosure relates to highly flexible and fluid-impermissible polymer coatings having improved adherence and performance properties on the metallic surfaces of the impeller housing mesh thus improving the overall performance of the percutaneous heart pumps.