An implantable cardiac system that includes an implantable cardiac pacemaker or leadless pacemaker (iLP) and a second device such as a subcutaneous implantable cardioverter-defibrillator (S-ICD). The pacemaker includes an R-spike amplifier that amplifies stimulated ventricle excitations or R-waves to increase R-wave to T-wave signal to noise ratio and to improve indirect detection of ventricular rhythm classification by the S-ICD. The S-ICD includes an electrode line for defibrillation, a sensing unit and a stimulation detection unit. The S-ICD records a subcutaneous electrocardiogram between shock electrode poles and provides potentially life-saving therapy based thereon. The system significantly increases the specificity and sensitivity of an S-ICD in combination with an implanted cardiac pacemaker or iLP having an R-spike amplifier.

A method of modifying tissue behavior, comprising: determining a desired modification of tissue behavior for at least one of treatment of a disease, short or long term modification of tissue behavior, assessing tissue state and assessing tissue response to stimulation; selecting an electric field having an expected effect of modifying protein activity of at least one protein as an immediate response of a tissue to the field, said expected effect correlated with said desired modification; and applying said field to said tissue.

A method for producing cardiomyocyte cells including implanting a substrate within a heart such that a first portion of the substrate is in physical contact with an endocardium and a second portion of the substrate is not in contact with the endocardium, maintaining the first portion of the substrate in contact with the endocardium for a time at least sufficient to form trabecular fibers extending between the endocardium and the second portion of the substrate, cutting away the trabecular fibers from the endocardium, cutting away the trabecular fibers from the substrate, and removing the trabecular fibers from the heart, wherein the trabecular fibers include cardiomyocyte cells.

A method for producing cardiomyocyte cells including implanting a substrate within a heart such that a first portion of the substrate is in physical contact with an endocardium and a second portion of the substrate is not in contact with the endocardium, maintaining the first portion of the substrate in contact with the endocardium for a time at least sufficient to form trabecular fibers extending between the endocardium and the second portion of the substrate, cutting away the trabecular fibers from the endocardium, cutting away the trabecular fibers from the substrate, and removing the trabecular fibers from the heart, wherein the trabecular fibers include cardiomyocyte cells.

The present disclosure provides, according to some embodiments, methods and systems for treatment or prevention of ventricular symptoms of atrial fibrillation. For example, methods for applying sub-threshold electric fields to Av node and associated tissue, for example, from inside a coronary sinus.

A method of therapeutically treating a subject includes the steps of: sensing sympathetic nerve activity; communicating the sensed sympathetic nerve activity to a processor; using machine learning in the processor to identify input data sets correlated to a physiological end point in the subject by processing the input data input sets to experientially optimize an algorithmically defined physiological goal defined in output data sets by the machine learning; and dynamically controlling a therapeutic device in real time with the processor using the output data sets to treat the subject mediated by the therapeutic device by establishing or tending to establish the physiological end point in the subject.

An external defibrillator system for assisting manual delivery of chest compressions and ventilations to a patient by a rescuer as cardiopulmonary resuscitation (CPR) includes a speaker, and a processor, memory, and associated circuitry coupled to the speaker. The processor is configured to initiate prompting for the chest compressions and the ventilations manually delivered to the patient by the rescuer as CPR, control the speaker to generate first auditory cues for the chest compressions, and control the speaker to generate second auditory cues for the ventilations with a different sound than the first auditory cues for the chest compressions. The first auditory cues and the second auditory cues assist the rescuer in timing the delivery of the chest compressions and the ventilations.

A method for producing cardiomyocyte cells including implanting a substrate within a heart such that a first portion of the substrate is in physical contact with an endocardium and a second portion of the substrate is not in contact with the endocardium, maintaining the first portion of the substrate in contact with the endocardium for a time at least sufficient to form trabecular fibers extending between the endocardium and the second portion of the substrate, cutting away the trabecular fibers from the endocardium, cutting away the trabecular fibers from the substrate, and removing the trabecular fibers from the heart, wherein the trabecular fibers include cardiomyocyte cells.

A method of modifying cardiac tissue behavior, comprising applying a therapeutically effective electric field having an effect of modifying protein activation levels of at least one protein, and repeatedly applying the field at time intervals timed to increase the activation levels of the at least one protein beyond an activation level achieved by natural and/or paced excitation of the muscle without the application, to an extent about at least as high as a decay of the activation between applications of the field.

The disclosure describes implantable medical systems that respond to occurrence of a lead-related condition by utilizing an elongated coil electrode in defining an alternative pacing therapy vector to maintain optimal drain of an IMD power supply. An exemplary system includes a medical electrical lead having an elongated electrode and an improved sensing and therapy delivery circuitry to provide the alternative pacing therapy vector responsive to the lead-related conditions. The system reconfigures the operation of the sensing and therapy delivery circuitry triggered by the switch to the alternative pacing therapy vector.