A ventricular support system including a light source, a fiber optic splitter, two or more filters, an intravascular blood pump having two or more sensor heads, and a photodetector is disclosed. At least some of the light transmitted by the light source is split by the fiber optic splitter such that a portion is transmitted to each of the two or more filters. Each portion of light is filtered by one of the two or more filters and transmitted to one of the two or more sensor heads. Light beams reflected from each of the two or more sensor heads are combined by the fiber optic splitter. At least some of the combined light beams are received by the photodetector. By only using a single light source and a single photodetector with the two or more sensor heads, the ventricular support system may have improved portability.

Method for determining a blood pressure value including the steps of: providing a pulsatility signal, determining a time-related feature and a normalized amplitude-related feature on the basis of the pulsatility signal; and calculating a blood pressure value on the basis of a blood pressure function depending on the time-related feature, the normalized amplitude-related feature and function parameters.

A torque coil 10 includes a first filar configured in an inner layer 14 that is helically wound in a constricted state such that it defines an inner lumen providing access between a proximal and distal end of the torque coil. A second filar is configured in an outer layer 18 that is helically wound over the inner layer in a constricted state. At least one of the first and second filars includes a signal transmitting material surrounded by an isolating material thereby allowing transmission of signals between the proximal and distal end of the torque coil in one of the layers. At least one of the first and second filars includes a torque transmitting material thereby configuring the torque coil to transfer torque from the proximal to the distal end.

A sleep apnea and obesity comorbidity treatment system includes a transceiver and a control module. The control module is configured to: receive sensor data, where the sensor data is indicative of a glucose level of a patient and a ketones level of the patient, transmit the sensor data to a remote feedback device, receive feedback information from the remote feedback device based on the sensor data, and where the feedback information provides indications to the patient to maintain or alter a behavior of the patient based on the glucose level and the ketones level, and based on the feedback information, performing an operation to maintain or alter at least one of a diet or physical activity of the patient.

The invention relates to restricting flow through a vascular access site such as an arteriovenous (AV) fistula or a graft using intravascular measurements to guide the procedure. The invention provides systems and methods for using intravascular detection to guide the restriction of flow through an AV fistula or graft. An intravascular instrument such as an imaging catheter or guidewire with measuring capabilities is inserted into a vessel proximal to an access site and used to evaluate the access site, which is banded to obtain healthy flow as indicated by the intravascular instrument. In certain aspects, the invention provides a method for improving a hemodialysis fistula or graft by inserting an intravascular instrument into a vessel proximal to the fistula or graft, making a measurement with the intravascular instrument, and restricting flow through the fistula or graft until the measurement obtains a predetermined value.

Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a medical device for measuring blood pressure. The medical device may include an elongated shaft having a proximal region and a distal region. An optical fiber may extend along the proximal region. The optical fiber may be secured to an inner surface of the shaft. An optical pressure sensor may be coupled to the optical fiber. The optical pressure sensor may be disposed along the distal region. A sealing member may be attached to the optical fiber and may have a surface engaged with the inner surface of the shaft.

Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a medical device for measuring blood pressure. The medical device may include an elongated shaft having a proximal region and a distal region. An optical fiber may extend along the proximal region. An optical pressure sensor may be coupled to the optical fiber. The optical pressure sensor may be disposed along the distal region. A centering member may be coupled to the optical fiber and positioned adjacent to the optical pressure sensor.

Medical devices and methods for making and using medical devices are disclosed. An example method may include a method for calculating fractional flow reserve including providing a pressure sensing guidewire, advancing the pressure sensing guidewire through a blood vessel to a first position distal of an intravascular occlusion, determining a distal pressure within the body lumen with the pressure sensing guidewire, proximally shifting the pressure sensing guidewire to a second position proximal of the occlusion, determining a proximal pressure within the body lumen with the pressure sensing guidewire, measuring an aortic pressure, and calculating a pressure drift. The pressure drift may be the difference between the aortic pressure and the proximal pressure. The method may also include calculating a drift-compensated fractional flow reserve. The drift-compensated fraction flow reserve may correspond to (the distal pressure+the pressure drift) divided by the aortic pressure.

A system and method are presented for detecting and measuring pressure within a region of a body lumen or vessel. The pressure sensing system includes a light source for transmitting light through a pathway of polarization maintaining fiber optic wire. A distal portion of the polarization maintaining fiber optic wire is engaged to and extends along a guidewire. The distal portion of the fiber optic wire includes pressure sensing station(s) made up of fiber Bragg gratings (FBG). The light transmitted to and reflected from the FBGs on the two polarization modes of the polarization maintaining fiber optic wire can be analyzed to provide one or more pressure values.

Medical devices including optical connector cable assemblies are disclosed. An optical connector cable assembly may include an optical connector cable having a first optical fiber extending therefrom. The optical connector cable may include a distal connector configured to connect to a guidewire. The distal connector may include an inner housing and a guidewire locking mechanism. The distal connector may also include an actuator. Actuation of the actuator may move the inner housing from a first position to a second position. When the inner housing is in the first position the guidewire locking mechanism is configured to secure the guidewire and the guidewire is rotatable with respect to the optical connector cable. When the inner housing is in the second position the guidewire locking mechanism is in an open state for receiving or removing the guidewire.