A balloon catheter device (400) of the present invention includes an elongate catheter shaft (401) comprising multifilar cable tubing having a proximal portion and a distal portion. The proximal portion includes a coating that allows the shaft to provide a patent fluid passage, and a part of the distal portion inside a balloon (406) may be uncoated or otherwise open to the balloon lumen, allowing for passage of fluid through the shaft into the balloon lumen.