Subcutaneous hemodynamic monitoring devices, systems and methods

Inventors

Garza, Aimee • Sewell, Tanzania

Assignees

Coravie Medical Inc

Abstract

An implantable sensor system using one or more sensor implants comprised of micro-electrical mechanical system (MEMS) sensors for the accurate and continuous measurement of physiological hemodynamic signals such as diastolic and systolic blood pressure. Sensor implants are configured to be subcutaneously injected to a placement site adjacent a blood vessel. In some embodiments, sensors comprise micromachined ultrasonic transducers.

Core Innovation

The invention provides an active hemodynamic monitoring system with a subcutaneous/injectable hemodynamic sensor implant configured to be placed within tissue adjacent a target blood vessel in a patient. The implant includes micromachined ultrasonic transducers, including pMUT/cMUT ultrasound transducers, controlled to send pulses and receive pulse echoes representing inner and outer walls of the target blood vessel at one or more sensing locations. The system generates data representative of the pulse echoes for subsequent hemodynamic determinations.

The system further provides sensing and data handling elements for patient condition and reliable measurements, including an accelerometer to detect patient movement and generate movement data, and a temperature sensor to detect patient temperature and generate temperature data. A communication module receives the ultrasound echo data and, when present, the movement and temperature data, and wirelessly transmits the received data for external processing. A local control module external to the patient wirelessly receives and relays the data to a computing device.

The computing device receives the relayed data and user input patient specific information comprising at least an initial patient diastolic blood pressure, and executes an instruction set to determine pulse wave velocity for the target blood vessel and blood pressure for the patient using at least the ultrasound echo data and the input patient specific information. The described approach supports deriving blood pressure over time based on pulse wave velocity and correlations referenced in the description (e.g., Ma et al.).

The implant includes tissue fixation mechanisms to secure the sensor implant in tissue spaced from the target blood vessel, including tissue adhesion promoting coatings and structural fixation means such as three-dimensional surface irregularities, tines, wings, or flaps. In certain embodiments, the tissue fixation is configured to secure the sensor implant at a sensing distance of about 2 mm to about 50 mm from an outer wall of the target blood vessel, including placement via an injection device configured to place the sensor implant at the specified sensing distance. The architecture also supports variations such as multiple ultrasound transducers at spaced sensing locations and transmitting echo data for pulse wave velocity and blood pressure determination.

Claims Coverage

The partial content provides four independent claims. Across these claims, the main inventive coverage centers on a subcutaneous sensor implant adjacent a target blood vessel using one or more ultrasound transducers at one or multiple sensing locations, optional patient-movement and temperature sensing, wireless data transmission with external local control, and computing blood pressure using pulse wave velocity together with an initial diastolic blood pressure input.

Across the independent claims, the core claim coverage is directed to subcutaneous sensor implants placed adjacent a target blood vessel that use ultrasound transducers to obtain pulse-echo data representing inner and outer vessel walls, optionally combine movement and temperature sensing, wirelessly transmit the data to an external local control, and compute pulse wave velocity and blood pressure using relayed ultrasound data together with an input comprising at least an initial diastolic blood pressure. Additional coverage is provided by specifying tissue fixation means, including adhesion-promoting coatings and structural fixation features, and, in one claim, securing the implant at a defined sensing distance from an outer vessel wall.

Stated Advantages

Documented Applications