Patent ID: 7909794

Claim:
A balloon catheter assembly comprising: a catheter body having a first lumen extending from a proximal end thereof through at least a portion of the length of the catheter body, the catheter body being provided with a fluid discharge aperture for discharging fluid from the lumen; a balloon secured to an exterior surface of the catheter body, the balloon being expandable between a relaxed state and an expanded state in response to a positive fluid pressure differential between the interior and the exterior of the lumen; the catheter body being formed with at least one balloon inflation aperture fluidly interconnecting the lumen and the interior of the balloon such that fluid from the lumen can be received in the balloon through the at least one balloon inflation aperture so as to result in expansion of the balloon from the catheter body; and an autoregulation valve provided on one of the balloon and the catheter body, the valve being adapted to restrict the flow of fluid through the fluid discharge aperture at fluid pressure differentials lower than a predetermined fluid pressure differential, and to expand a fluid flow path between the lumen and the fluid discharge aperture at pressure differential levels equal to or greater than the predetermined fluid pressure differential; the first lumen providing fluid flow and fluid communication with the balloon by way of the balloon inflation aperture and to exit the catheter by way of the fluid discharge aperture, wherein the autoregulation valve comprises a one-way valve including a valve seat provided within the catheter lumen proximally of the fluid discharge aperture, the seat being formed with a valve aperture therein in fluid communication with the lumen and having an internal diameter smaller than that of the lumen, a valve member disposed within the catheter lumen distally of the seat, and a valve spring disposed within the catheter lumen distally of the valve member and adapted to bias the valve member into seating engagement with the seat, the spring being selected to close the valve aperture at pressure levels within the lumen below the predetermined pressure differential, and to permit the valve to be lifted from engagement with the valve seat at pressure levels equal to or greater than the predetermined pressure differential, thereby opening the fluid discharge aperture to flow of fluid from the lumen.