Abstract: Delivery of an implantable wireless receiver-stimulator (R-S) into the heart using delivery catheter is described. R-S comprises a cathode and an anode and wirelessly receives and converts energy, such as acoustic ultrasound energy, to electrical energy to stimulate the heart. Conductive wires routed through the delivery system temporarily connect R-S electrodes to external monitor and pacing controller. R-S comprises a first temporary electrical connection from the catheter to the cathode, and a second temporary electrical connection from the catheter to the anode. Temporary electrical connections allow external monitoring of heart's electrical activity as sensed by R-S electrodes to determine tissue viability for excitation as well as to assess energy conversion efficiency.

Abstract: Method and systems for optimizing acoustic energy transmission in implantable devices are disclosed. Transducer elements transmit acoustic locator signals towards a receiver assembly, and the receiver responds with a location signal. The location signal can reveal information related to the location of the receiver and the efficiency of the transmitted acoustic beam received by the receiver. This information enables the transmitter to target the receiver and optimize the acoustic energy transfer between the transmitter and the receiver. The energy can be used for therapeutic purposes, for example, stimulating tissue or for diagnostic purposes.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: A controller-transmitter transmits acoustic energy through the body to an implanted acoustic receiver-stimulator. The receiver-stimulator converts the acoustic energy into electrical energy and delivers the electrical energy to tissue using an electrode assembly. The receiver-stimulator limits the output voltage delivered to the tissue to a predetermined maximum output voltage. In the presence of interfering acoustic energy sources output voltages are thereby limited prior to being delivered to the tissue. Furthermore, the controller-transmitter estimates the output voltage that is delivered to the tissue by the implanted receiver-stimulator. The controller-transmitter measures a query spike voltage resulting from the electrical energy delivered to the tissue by the receiver-stimulator, and computes a ratio of the predetermined maximum output voltage and a maximum query spike voltage. The maximum query spike voltage is computed by detecting a query spike voltage plateau.

Abstract: Delivery of an implantable wireless receiver-stimulator (R-S) into the heart using delivery catheter is described. R-S comprises a cathode and an anode and wirelessly receives and converts energy, such as acoustic ultrasound energy, to electrical energy to stimulate the heart. Conductive wires routed through the delivery system temporarily connect R-S electrodes to external monitor and pacing controller. R-S comprises a first temporary electrical connection from the catheter to the cathode, and a second temporary electrical connection from the catheter to the anode. Temporary electrical connections allow external monitoring of heart's electrical activity as sensed by R-S electrodes to determine tissue viability for excitation as well as to assess energy conversion efficiency.

Abstract: Method and systems for determining the location or identify of implantable devices are disclosed. An implantable device generates an electrical output and then modifies the output at a pre-configured interval for a pre-configured period. A sensor detects the modified output and locates or identifies the implantable device based on the modified output.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: Delivery of an implantable wireless receiver-stimulator (R-S) into the heart using delivery catheter is described. R-S comprises a cathode and an anode and wirelessly receives and converts energy, such as acoustic ultrasound energy, to electrical energy to stimulate the heart. Conductive wires routed through the delivery system temporarily connect R-S electrodes to external monitor and pacing controller. R-S comprises a first temporary electrical connection from the catheter to the cathode, and a second temporary electrical connection from the catheter to the anode. Temporary electrical connections allow external monitoring of heart's electrical activity as sensed by R-S electrodes to determine tissue viability for excitation as well as to assess energy conversion efficiency.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: Delivery of an implantable wireless receiver-stimulator (R-S) into the heart using delivery catheter is described. R-S comprises a cathode and an anode and wirelessly receives and converts energy, such as acoustic ultrasound energy, to electrical energy to stimulate the heart. Conductive wires routed through the delivery system temporarily connect R-S electrodes to external monitor and pacing controller. R-S comprises a first temporary electrical connection from the catheter to the cathode, and a second temporary electrical connection from the catheter to the anode. Temporary electrical connections allow external monitoring of heart's electrical activity as sensed by R-S electrodes to determine tissue viability for excitation as well as to assess energy conversion efficiency.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: Visual electrode ablation systems are described herein which include a deployment catheter and an attached imaging hood deployable into an expanded configuration. In use, the imaging hood is placed against or adjacent to a region of tissue to be imaged in a body lumen that is normally filled with an opaque bodily fluid such as blood. A translucent or transparent fluid, such as saline, can be pumped into the imaging hood until the fluid displaces any blood, thereby leaving a clear region of tissue to be imaged via an imaging element in the deployment catheter. An electric current may be passed through the fluid such that it passes directly to the tissue region being imaged and the electrical energy is conducted through the fluid without the need for a separate ablation probe or instrument to ablate the tissue being viewed.

Abstract: A method of ablating a tissue region within a blood-filled environment comprises restraining a fluid within a visualization field in a portion of the blood-filled environment and visualizing the tissue region through the fluid within the visualization field. The method also includes transmitting ablating electrical energy from the fluid into the visualized tissue region.

Abstract: Method and systems for optimizing acoustic energy transmission in implantable devices are disclosed. Transducer elements transmit acoustic locator signals towards a receiver assembly, and the receiver responds with a location signal. The location signal can reveal information related to the location of the receiver and the efficiency of the transmitted acoustic beam received by the receiver. This information enables the transmitter to target the receiver and optimize the acoustic energy transfer between the transmitter and the receiver. The energy can be used for therapeutic purposes, for example, stimulating tissue or for diagnostic purposes.

Abstract: Method and systems for optimizing acoustic energy transmission in implantable devices are disclosed. Transducer elements transmit acoustic locator signals towards a receiver assembly, and the receiver responds with a location signal. The location signal can reveal information related to the location of the receiver and the efficiency of the transmitted acoustic beam received by the receiver. This information enables the transmitter to target the receiver and optimize the acoustic energy transfer between the transmitter and the receiver. The energy can be used for therapeutic purposes, for example, stimulating tissue or for diagnostic purposes.

Abstract: Visual electrode ablation systems are described herein which include a deployment catheter and an attached imaging hood deployable into an expanded configuration. In use, the imaging hood is placed against or adjacent to a region of tissue to be imaged in a body lumen that is normally filled with an opaque bodily fluid such as blood. A translucent or transparent fluid, such as saline, can be pumped into the imaging hood until the fluid displaces any blood, thereby leaving a clear region of tissue to be imaged via an imaging element in the deployment catheter. An electric current may be passed through the fluid such that it passes directly to the tissue region being imaged and the electrical energy is conducted through the fluid without the need for a separate ablation probe or instrument to ablate the tissue being viewed.

Abstract: Method and systems for determining the location or identify of implantable devices are disclosed. An implantable device generates an electrical output and then modifies the output at a pre-configured interval for a pre-configured period. A sensor detects the modified output and locates or identifies the implantable device based on the modified output.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.