Systems and methods include a heat transfer body with opposing major surfaces formed from a thermally conductive substrate in intimate thermal interaction with an alumina exterior surface that extends across the major surfaces of the body. In an illustrative example, the heat source may be a substantially planar, silicone-based heater source (P-SBHS). The heat transfer body may be configured to thermally interact, for example, heat from a heat source proximate a first of the major surfaces to a second of the major surfaces. A temperature sensor module may be located, for example, proximate to the first major surface such that a temperature sensor thermally interacts with the first major surface. The temperature sensor module may, for example, insulate the temperature sensor from the P-SBHS.

A ventricular assist device incorporating a rotary pump, such as a rotary impeller pump is implantable in fluid communication with a ventricle and an artery to assist blood flow from the ventricle to the artery. The device includes a pump drive circuit supplying power to the pump, one or more sensors for sensing one or more electrophysiological signals such as electrogram signals in and a signal processing circuit connected to the sensors and the pump drive circuit. The signal processing circuit is operative to detect the sensor signals and control power supplied to the pump from the pump drive circuit so that the pump runs in a pulsatile mode, with a varying speed synchronized with the cardiac cycle. When an arrhythmia is detected, the pump drive circuit may also run the pump in an atrial arrhythmia mode or a ventricular arrhythmia mode different from the normal pulsatile mode.

A ventricular assist device incorporating a rotary pump, such as a rotary impeller pump is implantable in fluid communication with a ventricle and an artery to assist blood flow from the ventricle to the artery. The device includes a pump drive circuit supplying power to the pump, one or more sensors for sensing one or more electrophysiological signals such as electrogram signals in and a signal processing circuit connected to the sensors and the pump drive circuit. The signal processing circuit is operative to detect the sensor signals and control power supplied to the pump from the pump drive circuit so that the pump runs in a pulsatile mode, with a varying speed synchronized with the cardiac cycle so that it operates in copulsation or counterpulsation with the cycle. The cardiac cycle for purposes of synchronization can also be based on an average of two or more cardiac cycles.

Systems and methods for use in monitoring treatment of pressure-related conditions, such as hydrocephalus, include an implantable vessel, and a meter including one or more microfluidic channels connected to the vessel. The microfluidic channels may be configured to detect at least one of pressure and fluid flow rate through the vessel and to be read out remotely by a wirelessly coupled external device. The meter may include a passive resonant (LC) circuit. A dynamic flap may be included in the microfluidic channel that may act as part of the LC circuit. An external device may also be configured to inductively couple remotely to the LC circuit, with-out physical connections to the implantable vessel or pressure meter, and to display a pressure acting on the pressure meter and/or a fluid flow through the meter.

A driveline and driveline system for an active implantable device provides for communication over the power conductors in the driveline. The driveline includes four conductors, two for the positive power connection and two for the negative power connection. Communication in the driveline is performed using Power Line Communication (PLC) technology on the four conductors, superimposing a communication signal on the conductors such that the four conductors provide both power and communication capability. The four conductors provide redundant paths for both power and communication, so the failure of one of the conductors in the driveline does not affect operation of the driveline. The four conductor driveline cable and system provides a more robust driveline cable that does not fail with the failure of one of the conductors without increasing the diameter of the driveline, which would increase the risk of infection where the driveline passes through the skin.

Systems and methods for use in monitoring treatment of pressure-related conditions, such as hydrocephalus, include an implantable vessel, and a meter including one or more microfluidic channels connected to the vessel. The microfluidic channels may be configured to detect at least one of pressure and fluid flow rate through the vessel and to be read out remotely by a wirelessly coupled external device. The meter may include a passive resonant (LC) circuit. A dynamic flap may be included in the microfluidic channel that may act as part of the LC circuit. An external device may also be configured to inductively couple remotely to the LC circuit, with-out physical connections to the implantable vessel or pressure meter, and to display a pressure acting on the pressure meter and/or a fluid flow through the meter.

A ventricular assist device incorporating a rotary pump, such as a rotary impeller pump is implantable in fluid communication with a ventricle and an artery to assist blood flow from the ventricle to the artery. The device includes a pump drive circuit supplying power to the pump, one or more sensors for sensing one or more electrophysiological signals such as electrogram signals in and a signal processing circuit connected to the sensors and the pump drive circuit. The signal processing circuit is operative to detect the sensor signals and control power supplied to the pump from the pump drive circuit so that the pump runs in a pulsatile mode, with a varying speed synchronized with the cardiac cycle so that it operates in copulsation or counterpulsation with the cycle. The cardiac cycle for purposes of synchronization can also be based on an average of two or more cardiac cycles.

A ventricular assist device incorporating a rotary pump, such as a rotary impeller pump is implantable in fluid communication with a ventricle and an artery to assist blood flow from the ventricle to the artery. The device includes a pump drive circuit supplying power to the pump, one or more sensors for sensing one or more electrophysiological signals such as electrogram signals in and a signal processing circuit connected to the sensors and the pump drive circuit. The signal processing circuit is operative to detect the sensor signals and control power supplied to the pump from the pump drive circuit so that the pump runs in a pulsatile mode, with a varying speed synchronized with the cardiac cycle. When an arrhythmia is detected, the pump drive circuit may also run the pump in an atrial arrhythmia mode or a ventricular arrhythmia mode different from the normal pulsatile mode.

Systems and methods are provided for regulating the transfer of energy inductively between an implantable device and an external charging system, wherein the energy transfer rate is regulated by varying an operating frequency of an inductive energy transfer circuit of the implantable device responsive a temperature measured within the implantable device.

Systems and methods include a heat transfer body with opposing major surfaces formed from a thermally conductive substrate in intimate thermal interaction with an alumina exterior surface that extends across the major surfaces of the body. In an illustrative example, the heat source may be a substantially planar, silicone-based heater source (P-SBHS). The heat transfer body may be configured to thermally interact, for example, heat from a heat source proximate a first of the major surfaces to a second of the major surfaces. A temperature sensor module may be located, for example, proximate to the first major surface such that a temperature sensor thermally interacts with the first major surface. The temperature sensor module may, for example, insulate the temperature sensor from the P-SBHS.