Pigtail catheters and relates methods for measuring a pressure gradient across a bodily narrowing are disclosed. A pigtail catheter can comprise a proximal shaft segment and a distal shaft segment. The proximal shaft segment can include double lumen tubing defining a proximal pressure lumen and a non-coaxial, distal pressure lumen. In an example, the distal pressure lumen has a generally circular cross-sectional shape, and the proximal pressure lumen has a generally crescent or kidney cross-sectional shape that wraps partially around the distal pressure lumen. The distal shaft segment can include at least one distal orifice positionable distal to the bodily narrowing and at least one proximal orifice positionable proximal to the bodily narrowing. Each orifice can have a diameter of at least about 0.018 inches, for example. A manifold can be coupled to a proximal end of the proximal shaft segment and can include a proximal pressure port in communication with the proximal pressure lumen and a distal pressure port in communication with the distal pressure lumen.

An intravascular sensor device can be used to guide treatment of a diseased blood vessel in the body of a patient. In some examples, the intravascular sensor device includes a pressure sensor and an ultrasound transducer. The intravascular sensor device is used to measure a pressure within the diseased blood vessel and acquire an ultrasound image of the diseased blood vessel. The pressure may be measured during hyperemic blood flow that is caused by a pharmacologic vasodilator drug. The measured pressure can be used to calculate a fractional flow reserve value. The ultrasound image can be used to determine a physical dimension of the blood vessel, such as cross-sectional area. The fractional flow reserve value and physical dimensions of the blood vessel can be used to optimize patient treatment.

An apparatus for assessing the severity of stenosis in a blood vessel includes an elongate body including a distal portion and a centering assembly. The centering assembly is actuatable to selectively center the elongate body in the vessel. A pressure sensor is disposed adjacent the centering assembly and is configured to detect fluid pressure in the vessel. A processing system receives the measured pressure from the pressure sensor, receives data representing the cross-sectional area of the vessel, receives data representing the size of the distal portion, calculates a offset correlation based on the size of the distal portion and based on the size of the vessel, and calculates a fractional flow reserve (FFR) for the vessel as an index of stenosis severity taking into account the offset correlation and the measured fluid pressure from the pressure sensor.

A system includes a processor circuit configured to receive a first set of data. The first set of data includes two pressure measurements and a flow measurement from the vasculature of a patient obtained while the sympathetic nervous system of the patient is not under stimulation. The processor circuit calculates a blood flow resistance value based on the first set of data. The processor circuit then receives a second set of data. The second set of data also includes two pressure measurements and a flow measurement from the vasculature of the patient obtained while the sympathetic nervous system of the patient is stimulated. The processor circuit calculates another blood resistance value based on the second set of data. The processor circuit then compares the two blood flow resistance values to determine whether a denervation procedure would be effective to mitigate the nerve system's response to stimulation. The processor circuit outputs to a screen display metrics obtained from the measurement procedure.

A system includes a processor circuit in communication with an anatomical measurement device. The anatomical measurement device receives a metric associated with a sympathetic response of a patient. The sympathetic nervous system of the patient is then stimulated. The anatomical measurement device then receives another metric associated with a sympathetic response of the patient while the sympathetic nervous system is stimulated. The processor circuit then provides an output based on the comparison.

Systems for determining fractional flow reserve are disclosed. An example system may include a pressure sensing guidewire for measuring a first pressure, a second pressure sensing medical device for measuring a second pressure, and a processor coupled to the pressure sensing guidewire and coupled to the second pressure sensing medical device. The processor may be designed to generate a plot of the magnitude of the second pressure over time, identify one or more time intervals of the plot that have a slope less than zero, determine a mean of the second pressure, and calculate the ratio of the first pressure to the second pressure when (a) the second pressure is less than or equal to the mean of the second pressure and (b) during the one or more time intervals when the slope of the plot is less than zero.

Disclosed herein is a stent antenna that is inserted into a body and used, including a main branch having a mesh shape, a plurality of branched branches which are branched off from the main branch and each have a mesh shape, and a feed line connected to the main branch to supply power to the stent antenna.

In part, the disclosure relates to computer-based methods, devices, and systems suitable for performing intravascular data analysis and measurement of various types of data such as pressure and flow data. The disclosure relates to probes and methods suitable for determining an event in a cardiac cycle such as flow threshold such as a peak flow, a fraction thereof, other intravascular parameters or a point in time during which peak flow or a change in one of the parameters occurs. An exemplary probe includes one or more of a pressure sensor, a resistor, a flow sensor and can be used to generate diagnostic data based upon measured intravascular and other parameters. In part, the disclosure relates to methods and systems suitable for determining a coronary flow reserve value in response to one or more of intravascular pressure and flow data or data otherwise correlated therewith.

A prosthetic valve comprises a frame assembly having a first opening at an inflow portion of the frame assembly and a second opening at an outflow portion of the frame assembly, a first sensor device situated at the inflow portion of the frame, and a second sensor device situated at the outflow portion of the frame. Each of the first sensor device and the second sensor device is configured to sense a physical parameter and provide a sensor signal. The prosthetic valve further comprises a transmitter assembly configured to receive the sensor signals from the first sensor device and the second sensor device and wirelessly transmit a transmission signal based at least in part on the sensor signals.

A sensor implant device includes a shunt structure comprising a flow path conduit and a plurality of arms configured to secure the shunt structure to a tissue wall, and a pressure sensor device attached to one of the plurality of arms of the shunt structure. The pressure sensor device comprises one or more sensor elements, an antenna, control circuitry electrically coupled to the one or more sensor elements and the antenna, and a housing that houses the control circuitry.