Medical electrical leads equipped with spacer elements and configured for use during medical procedures such as magnetic resonance imaging (MRI) are disclosed. An illustrative medical electrical lead includes a proximal connector, an insulated lead body including at least one electrode, a helically coiled conductor wire, and a helically coiled spacer element interstitially disposed between adjacent turns of the conductor wire.

An implantable medical device (IMD) is adapted for detecting acoustic chest sounds. The IMD includes a pulse generator having a compartment, the compartment defining an isolated cavity bounded by a back wall. A diaphragm is disposed over and encloses the cavity. An acoustic sensor adapted to sense chest sounds and generate a signal is disposed between the diaphragm and the back wall. The IMD also includes a control circuit disposed within the pulse generator. The circuit is operatively coupled to the acoustic sensor and is adapted to receive the signal.

A device and method for removing a guide catheter from about a cardiac lead is disclosed. The device includes a blade for slitting the catheter so that the catheter may be removed from the lead. The blade includes upper and lower angled cutting surfaces which define a notch. The device includes a portion for receiving the lead and guiding the catheter to the blade.

A system for selective activation of a nerve trunk using a transvascular reshaping lead is provided. One aspect of this disclosure relates to a system for spreading nerve bundles in a nerve trunk. The system includes a lead adapted to be chronically implanted in a blood vessel proximate a nerve trunk, and having an expandable portion adapted to be expanded to reshape the blood vessel to an elongated shape and to reshape the nerve trunk into an elongated shape to spread nerve bundles of the nerve trunk. The system also includes a plurality of electrodes and an implantable device coupled to the lead, where an electrical signal is delivered from the implanted medical device to one of the plurality of electrodes to transvascularly deliver neural stimulation from the electrode to at least one of the nerve bundles of the nerve trunk. Other aspects and embodiments are provided herein.

A method comprising detecting a ventricular tachycardia heart rhythm in a patient, providing anti-tachycardia pacing (ATP) therapy to the patient in response to the ventricular tachycardia heart rhythm, waiting a first time duration after the ATP therapy ends, and monitoring ventricular depolarizations after the first time duration has elapsed. The monitoring includes measuring time intervals between the ventricular depolarizations, and if a consecutive number of the intervals between the ventricular depolarizations are shorter than a first threshold interval value, then the method includes deeming that the ventricular tachycardia rhythm persists. Otherwise, if a fraction of the intervals between the ventricular depolarizations are shorter than a second threshold interval value, then the method includes deeming that the ventricular tachycardia heart rhythm persists, and otherwise deeming that the ventricular tachycardia rhythm is converted.