Abstract: Methods, systems and computer program products for cardiac pacing are provided. For pacing using biventricular synchronization in a patient, a first stimulation signal is applied to a first region of a heart of the patient at a first time and a second stimulation signal applied to a second region of the heart of the patient at a second time to provide biventricular synchronization stimulation of the heart. Cardiac function of the patient associated with application of the first and the second stimulation signals is sensed and a timing relationship of the first stimulation signal to the second stimulation signal is adjusted based on the sensed cardiac function.

Abstract: A passive conductor assembly for use with an implanted stimulating device having an intracavitarily or transvenously disposed electrode is disclosed. The passive conductor assembly used in combination with the implanted stimulus generator having an intracavitarily or intravenously disposed electrode includes at least one conductive element having a first end and a second end, and/or other contacting sites for contacting a portion of a heart of a subject to be stimulated. The passive conductor is disposed in proximity to the intracavitarily or transvenous electrode which is connected to the implanted stimulus generator such as a pacemaker or defibrillator.

Abstract: Methods, systems and computer program products for combining atrial defibrillation treatment techniques include techniques for reducing the discomfort associated with defibrillation and/or reducing the defibrillation threshold. Techniques include timing the defibrillation shock to reduce discomfort based on a sensed signal, giving the shock relatively early during atrial fibrillation, therapeutic drugs, administering more than one shock in succession, pacing the heart before, after, or during the defibrillation shock or shocks, and placing the shock electrodes in locations that may reduce discomfort.

Abstract: An implantable system for the defibrillation of the atria of a patient's heart comprises (a) a first catheter configured for insertion into the right atrium of the heart, preferably without extending into the right ventricle of the heart; a first atrial defibrillation electrode carried by the first catheter and positioned at the atrial septum of the heart (i.e., an atrial septum electrode); (b) a second atrial defibrillation electrode which together with the first atrial defibrillation electrode provides a pair of atrial defibrillation electrodes that are configured for orientation in or about the patient's heart to effect atrial defibrillation, and (c) a pulse generator operatively associated with the pair of atrial defibrillation electrodes for delivering a first atrial defibrillation pulse to the heart of the patient. The second electrode may be configured for positioning through the coronary sinus ostium and in the coronary sinus or a vein on the surface of the left ventricle, such as the great vein.

Abstract: Methods, systems and computer program products determine and identify a favorable time to deliver cardiac compression to a subject to avoid a vulnerable period of a spontaneous intrinsic cardiac cycle.

Abstract: Electrical activity can be chronically detected in first and second cardiac regions in the subject. Discordant alternans in at least one component of the detected electrical activity can by identified. Interventional therapy can be initiated in the subject responsive to the identification of discordant alternans.

Abstract: Methods for defibrillating a heart in fibrillation can include detecting fibrillation of the heart and applying a defibrillation stimulus to a fastest activating region of the fibrillating heart. Applying electrical stimuli to the region of the heart containing the fastest activating region may cause the “mother rotor” to halt, thereby interrupting fibrillation of the heart. Alternatively, applying the electrical stimuli to a region of a heart not in fibrillation but is likely to include the mother rotor during fibrillation may reduce the likelihood that fibrillation may occur in the heart.

Abstract: An implantable system for the defibrillation of the atria of a patient's heart comprises (a) a first catheter configured for insertion into the right atrium of the heart; a first atrial defibrillation electrode carried by the first catheter and positioned to stimulate Bachmann's bundle, or positioned at the atrial septum of the heart (i.e., an atrial septum electrode); (b) a second atrial defibrillation electrode which together with the first atrial defibrillation electrode provides a pair of atrial defibrillation electrodes that are configured for orientation in or about the patient's heart to effect atrial defibrillation, and (c) a pulse generator operatively associated with the pair of atrial defibrillation electrodes for delivering a first atrial defibrillation pulse to the heart of the patient. The second electrode may be configured for positioning through the coronary sinus ostium and in the coronary sinus or a vein on the surface of the left ventricle, such as the great vein.