Leadless pacemaker system

A system comprising:

• a ventricular pacing device configured for implantation within a ventricle of a heart, the ventricular pacing device configured to sense intrinsic ventricular depolarizations and one of:
• inhibit delivery of pacing pulses responsive to sensed intrinsic ventricular depolarizations;
• or
• deliver pacing pulses to the ventricle responsive to an absence of sensed intrinsic ventricular depolarizations;
• and
• an atrial pacing device configured for implantation within an atrium of the heart, the atrial pacing device being operable without receiving communication from the ventricular pacing device and being configured to:
• detect ventricular activation events;
• and
• deliver pacing pulses to the atrium, each pacing pulse of the pacing pulses being timed based on when respective ventricular activation events are detected by the atrial pacing device;
• wherein the atrial pacing device is configured to deliver pacing pulses at an atrial pacing rate, and wherein the ventricular pacing device is configured to deliver pacing pulses at a ventricular pacing rate that is less than the atrial pacing rate.

A system comprising:

• a ventricular pacing device configured for implantation within a ventricle of a heart, the ventricular pacing device configured to sense intrinsic ventricular depolarizations and one of:
• inhibit delivery of pacing pulses responsive to sensed intrinsic ventricular depolarizations;
• or
• deliver pacing pulses to the ventricle responsive to an absence of sensed intrinsic ventricular depolarizations;
• and
• an atrial pacing device configured for implantation within an atrium of the heart, the atrial pacing device being operable without receiving communication from the ventricular pacing device and being configured to:
• detect ventricular activation events;
• and
• deliver pacing pulses to the atrium, each pacing pulse of the pacing pulses being timed based on when respective ventricular activation events are detected by the atrial pacing device;
• wherein the atrial pacing device is configured to:
• determine a length of an interval between a ventricular activation event of the ventricular activation events and a respective previous atrial event;
• schedule a time at which to deliver a pacing pulse of the pacing pulses to the atrium based on the length of the interval;
• and
• control the delivery of the pacing pulse of the pacing pulses at the scheduled time.

A method comprising:

• sensing intrinsic ventricular depolarizations of a ventricle of a heart using a ventricular pacing device configured for implantation within the ventricle;
• delivering pacing pulses to the ventricle of the heart using the ventricular pacing device responsive to an absence of the sensed intrinsic ventricular depolarizations;
• detecting ventricular activation events using an atrial pacing device that is operable without receiving communication from the ventricular pacing device and configured for implantation entirely within an atrium of the heart;
• and
• delivering, by the atrial pacing device, pacing pulses to the atrium, each pacing pulse of the pacing pulses being timed based on when respective ventricular activation events are detected by the atrial pacing device.

A method comprising:

• sensing intrinsic ventricular depolarizations of a ventricle of a heart using a ventricular pacing device configured for implantation within the ventricle;
• delivering pacing pulses to the ventricle of the heart using the ventricular pacing device;
• detecting ventricular activation events using an atrial pacing device that is operable without receiving communication from the ventricular pacing device and configured for implantation within an atrium of the heart;
• delivering, by the atrial pacing device, pacing pulses to the atrium, each pacing pulse of the pacing pulses being timed based on when respective ventricular activation events are detected by the atrial pacing device;
• delivering pacing pulses at an atrial pacing rate using the atrial pacing device;
• and
• delivering pacing pulses at a ventricular pacing rate that is less than the atrial pacing rate using the ventricular pacing device.

A method comprising:

• sensing intrinsic ventricular depolarizations of a ventricle of a heart using a ventricular pacing device configured for implantation within the ventricle;
• delivering pacing pulses to the ventricle of the heart using the ventricular pacing device;
• detecting ventricular activation events using an atrial pacing device that is operable without receiving communication from the ventricular pacing device and configured for implantation within an atrium of the heart;
• delivering, by the atrial pacing device, pacing pulses to the atrium, each pacing pulse of the pacing pulses being timed based on when the ventricular activation events are detected by the atrial pacing device;
• delivering pacing pulses at an atrial pacing rate using the atrial pacing device;
• delivering pacing pulses at a ventricular pacing rate that is less than the atrial pacing rate using the ventricular pacing device;
• determining a length of an interval between a ventricular activation event of the ventricular activation events and a respective previous atrial event;
• scheduling a time at which to deliver a pacing pulse of the pacing pulses to the atrium based on the length of the interval;
• and
• controlling the delivery of the pacing pulse of the pacing pulses at the scheduled time.

A system comprising:

• a first pacing device configured for implantation entirely within a first chamber of a heart, the first pacing device configured to sense intrinsic depolarizations of the first chamber of the heart and one of:
• inhibit delivery of pacing pulses responsive to sensed intrinsic depolarizations of the heart;
• or
• deliver pacing pulses to the heart responsive to an absence of sensed intrinsic depolarizations of the heart;
• and
• a second pacing device configured for implantation entirely within a second chamber of the heart, the second pacing device being operable without a communication link between the first pacing device and the second pacing device, wherein the second pacing device is configured to deliver pacing pulses to the heart timed based on when respective events, from a chamber of the heart different from the second chamber, are detected by the second pacing device.