An implantable system includes an implantable medical device (IMD) and a non-transvenous lead that is configured to be implanted outside of a heart. The IMD includes an output configured to be connected at least to the lead, a current generator (CG) circuit configured to generate pacing pulses, a switching circuit coupled between the CG circuit and the output, one or more capacitors coupled in parallel with the CG circuit and the switching circuit, and a control circuit coupled to the CG circuit. The control circuit is configured to manage the CG circuit to generate the pacing pulses with a constant current at the output.

An implantable system includes an implantable medical device (IMD) and a non-transvenous lead that is configured to be implanted outside of a heart. The IMD includes an output configured to be connected at least to the lead, a current generator (CG) circuit configured to generate pacing pulses, a switching circuit coupled between the CG circuit and the output, one or more capacitors coupled in parallel with the CG circuit and the switching circuit, and a control circuit coupled to the CG circuit. The control circuit is configured to manage the CG circuit to generate the pacing pulses with a constant current at the output.

According to some embodiments, a method of confirming successful ablation of targeted cardiac tissue of a subject using a high-resolution mapping electrode comprises pacing said cardiac tissue at a predetermined pacing level to increase the heart rate of the subject from a baseline level to an elevated level, the predetermined pacing level being greater than a pre-ablation pacing threshold level but lower than a post-ablation pacing threshold level, delivering ablative energy to the ablation electrode, detecting the heart rate of the subject, wherein the heart rate detected by the high-resolution mapping electrode is at the elevated level before the post-ablation pacing threshold level is achieved, and wherein the heart rate detected by the high-resolution mapping electrode drops below the elevated level once ablation achieves its therapeutic goal or target, and terminating the delivery of ablative energy to the ablation electrode after the heart rate drops below the elevated level.

Implantable devices and systems include one or more leads adapted to be emplaced in the internal thoracic vein (ITV) of a patient. The lead may include features to adapt the lead for such placement. An associated device for use with the lead may include operational circuitry adapted for use with a lead having an electrode for sensing and/or therapy purposes coupled thereto. Methods for implantation and use of such devices and systems are disclosed as well.

Implantable devices and systems include one or more leads adapted to be emplaced in the internal thoracic vein (ITV) of a patient. The lead may include features to adapt the lead for such placement. An associated device for use with the lead may include operational circuitry adapted for use with a lead having an electrode for sensing and/or therapy purposes coupled thereto. Methods for implantation and use of such devices and systems are disclosed as well.

Systems and methods for treating a medical condition such as worsening heart failure (WHF) are described. A medical system may sense one or more physiological signals, and generate from the sensed physiological signals a signal metric trend indicating a progression of heart failure. A detector may detect a physiological event leading to WHF. A therapy control circuit may generate a therapy titration protocol using the generated signal metric trend. The therapy titration protocol includes a temporal profile of therapy dosage relative to a target dosage. The therapy control circuit may adjust the target dosage based on patient response. Therapies may be administered by a clinician or automatically delivered to the patient according to the therapy titration protocol.

Systems and methods for treating a medical condition such as worsening heart failure (WHF) are described. A medical system may sense one or more physiological signals, and generate from the sensed physiological signals a signal metric trend indicating a progression of heart failure. A detector may detect a physiological event leading to WHF. A therapy control circuit may generate a therapy titration protocol using the generated signal metric trend. The therapy titration protocol includes a temporal profile of therapy dosage relative to a target dosage. The therapy control circuit may adjust the target dosage based on patient response. Therapies may be administered by a clinician or automatically delivered to the patient according to the therapy titration protocol.

An implantable system for stimulating a human/animal heart, comprising a processor, a memory unit, a stimulation unit, a sensing unit, and a diagnostic unit. The system carries out: a) detecting whether at least one malfunction state of the system is present; b) checking whether an electrode provided for stimulating a His bundle of a heart is connected to the stimulation unit; c) switching an operating state of the system into a safety mode when a malfunction state was detected, the safety mode selected from a first safety mode and a second safety mode, wherein i) the first safety mode is selected when no electrode provided for stimulating a His bundle of a heart is connected to the stimulation unit, and ii) the second safety mode is selected when an electrode provided for stimulating a His bundle of a heart is connected to the stimulation unit.

An implantable system for stimulating a human/animal heart, comprising a processor, a memory unit, a stimulation unit, a sensing unit, and a diagnostic unit. The system carries out: a) detecting whether at least one malfunction state of the system is present; b) checking whether an electrode provided for stimulating a His bundle of a heart is connected to the stimulation unit; c) switching an operating state of the system into a safety mode when a malfunction state was detected, the safety mode selected from a first safety mode and a second safety mode, wherein i) the first safety mode is selected when no electrode provided for stimulating a His bundle of a heart is connected to the stimulation unit, and ii) the second safety mode is selected when an electrode provided for stimulating a His bundle of a heart is connected to the stimulation unit.

A medical having a motion sensor is configured to set an atrial event sensing parameter used for sensing atrial event signals from a motion signal produced by the motion sensor. The medical device sets an atrial event sensing parameter by applying a sensing window during each one of multiple ventricular cycles, determining a feature of the motion signal during the sensing window for at least a portion of the ventricular cycles, and setting the atrial event sensing parameter based on the determined features. The medical device may sense the atrial event from the motion signal according to the atrial event sensing parameter.