A leadless pacemaker (100, 200, 300) and trailing (1, 3, 5) and leading (2, 4, 6) components thereof are disclosed. The trailing component (1, 3, 5) includes a first connecting member (12, 32) and a second connecting member (13), and the leading component (2, 4, 6) includes a third connecting member (23, 42, 62) and a fourth connecting member (24, 63). The first connecting member (12, 32) is configured to be detachably connected to the third connecting member (23, 42, 62) and the second connecting member (13) is configured to be detachably or non-detachably connected to the fourth connecting member (24, 63), thereby achieving interlocking between the trailing component (1, 3, 5) and the leading component (2, 4, 6). Additionally, both the first connecting member (12, 32) and the third connecting member (23, 42, 62) are non-biodegradable. At least one of the second connecting member (13) and the fourth connecting member (24, 63) is biodegradable, or the second connecting member (13) is fitted and connected to the fourth connecting member (24, 63) by an associated biodegradable connecting member. Thus, before the connecting member is degraded, it can be ensured that the trailing component (1, 3, 5) and the leading component (2, 4, 6) are firmly connected together by the four connecting members, facilitating overall retrieval or adjustment of the pacemaker (100, 200, 300). Moreover, after the connecting member is degraded, the trailing component (1, 3, 5) can be easily retrieved.

A leafless biostimulator, such as a leadless pacemaker, includes a housing sized and configured to be implanted within a heart of a patient and includes both primary and secondary fixation features. The primary fixation feature is adapted to rotate to fix the leadless biostimulator to a wall of the heart during initial implantation. Once the leadless biostimulator is implanted, the secondary fixation feature is adapted to resist counter-rotation of the leadless biostimulator. The primary fixation feature may include a fixation helix configured to affix the housing to the heart by rotating in a screwing direction. The secondary fixation feature may include an apex to engage the heart to resist unscrewing of the primary fixation feature.

Delivery devices, systems, and methods for delivering implantable leadless pacing devices are disclosed. An example delivery device may include an outer tubular member including a lumen extending from a proximal end to a distal end thereof and an intermediate tubular member including a lumen extending from a proximal end to a distal end thereof. A distal holding section may be coupled to the intermediate tubular member and define a cavity therein for receiving a proximal implantable leadless pacing device and a distal implantable leadless pacing device in a linear arrangement. The distal holding section may have a proximal body portion and a distal body portion. The proximal body portion may be more flexible than the distal body portion. An inner tubular member including a lumen extending from a proximal end to a distal end thereof may be slidably disposed within the lumen of the intermediate tubular member.

The invention features methods and devices useful for stimulating brain tissue in a subject via electrodes within cranial bone. These methods and devices may be utilized for the detection, prevention, and/or treatment of neurological disorders via electric stimulation. Additionally, the methods and devices disclosed herein may be useful for the treatment, inhibition, and/or arrestment of the growth of tumors.

An example device for detecting one or more parameters of a cardiac signal is disclosed herein. The device includes one or more electrodes and sensing circuitry configured to sense a cardiac signal via the one or more electrodes. The device further includes processing circuitry configured to determine an R-wave of the cardiac signal and determine whether the R-wave is noisy. Based on the R-wave being noisy, the processing circuitry is configured to determine whether the cardiac signal around a determined T-wave is noisy. Based on the cardiac signal around the determined T-wave not being noisy, the processing circuitry is configured to determine a QT interval or a corrected QT interval based on the determined T-wave and the determined R-wave.

Techniques are described for providing a therapeutic pseudo-constant DC current in an implantable stimulator using pulses whose positive and negative phases are not charge balanced. Such charge imbalanced pulses act to charge any capacitance in the current path between selected electrode nodes, such as the DC-blocking capacitors and/or any inherent capacitance such as those present at the electrode/tissue interface. These charged capacitances act during quiet periods between the pulses to induce a pseudo-constant DC current. Beneficially, these DC currents can be small enough to stay within charge density limits and hence not corrode the electrode or cause tissue damage, and further can be controlled to stay within such limits or for other reasons. Graphical user interface (GUI) aspects for generating the charge imbalanced pulses and for determining and/or controlling the pseudo-constant DC current are also provided.

A system may include a leadless cardiac pacing device including a body, a proximal hub, and a helical fixation member opposite the proximal hub; and a first elongate shaft having a lumen extending from a distal end of the elongate shaft proximally into the elongate shaft and a transverse member extending transversely across the lumen. The proximal hub may include a transverse channel extending into the proximal hub, the transverse channel being configured to engage the transverse member.

Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), subcutaneous implantable cardioverter defibrillators (SICD), transvenous implantable cardioverter defibrillators, neuro-stimulators (NS), implantable monitors (IM), may be configured to communicate with each other. In some cases, a first IMD may transmit instructions to a second IMD. In order to improve the chances of a successfully received transmission, the first IMD may transmit the instructions several times during a particular time frame, such as during a single heartbeat. If the second IMD receives the message more than once, the second IMD recognizes that the messages were redundant and acts accordingly.

An implantable leadless cardiac pacing device and associated retrieval features. The implantable device includes a docking member extending from the proximal end of the housing of the implantable device including a covering surrounding at least a portion of the docking member configured to facilitate retrieval of the implantable leadless cardiac pacing device.

A leadless cardiac pacemaker is provided which can include any number of features. In one embodiment, the pacemaker can include a tip electrode, pacing electronics disposed on a p-type substrate in an electronics housing, the pacing electronics being electrically connected to the tip electrode, an energy source disposed in a cell housing, the energy source comprising a negative terminal electrically connected to the cell housing and a positive terminal electrically connected to the pacing electronics, wherein the pacing electronics are configured to drive the tip electrode negative with respect to the cell housing during a stimulation pulse. The pacemaker advantageously allows p-type pacing electronics to drive a tip electrode negative with respect to the can electrode when the can electrode is directly connected to a negative terminal of the cell. Methods of use are also provided.