Single sensor pressure differential device

A method of sensing the pressure differential between two spaced-apart locations in a biological fluid-filled vessel comprising the steps of:

• providing a pressure sensor having a transducer, a catheter body coupled to the transducer, and an elongated conduit having one end adjoining the transducer and another end spaced from the transducer;
• inserting the sensor into the vessel with a portion of the catheter body extending externally from the vessel;
• manipulating the sensor to a region of interest in the vessel including the substeps of positioning the transducer at a first location in the vessel and positioning the conduit other end at a second location in the vessel spaced from the first location;
• filling the conduit with fluid so that the fluid-filled conduit is indicative of the fluid pressure at the second location;
• and
• sensing, with the transducer positioned in the region of interest and the conduit filled with fluid, the pressure differential between the fluid adjoining one side of the transducer in the vessel at said first location and the fluid at said second location.

An angioplasty catheter for sensing the blood pressure differential between spaced locations in a blood vessel, comprising:

• an elongated catheter body;
• a housing coupled to one end of the catheter body and adapted to be received in the blood vessel;
• a guidewire-receiving passage coupled to the housing;
• dilation means coupled to the housing and having a balloon selectably outwardly expandable from the housing;
• and
• means coupled to the housing for sensing the pressure differential between locations on each side of the balloon with the housing received in the blood vessel, including--
• a deformable member mounted to the housing proximal relative to the balloon and having an outer surface oriented outwardly away from the housing and an inner surface oriented inwardly into the housing,
• a conduit coupled to the housing having one end opening at a location distal relative to the balloon and another end adjoining the inner surface of the member, and
• means coupled to the member for indicating the deformation of the member in response to a blood pressure differential across the member, the indicating means including elongated electrical leads received in the catheter body.