Multi-electrode cardiac lead adapter with multiplexer

An adapter connected between a cardiac lead having a distal end including a plurality of electrodes adapted to contact a patient's heart and a proximal end having plurality of terminals, each terminal being connected to one electrode, and a cardiac stimulation device capable of functioning with less electrodes than the number of electrodes in said lead and including a sensing and a stimulation contact, said adapter comprises:

• a first connector that receives said plurality of connector terminals of the cardiac lead;
• a first multiplexer having an input connected to said first connector, a selector connected to the input to couple a first group of electrodes of said cardiac lead, and an output to transfer sensing signals from said first group of electrodes;
• a second multiplexer having an input connected to said first connector,
• a selector connected to said input to couple a second group of electrodes of said cardiac lead, and an output to transfer pacing signals to said second group of electrodes;
• and
• a second connector having contacts connected to said cardiac stimulation device and said output of said multiplexer to transfer said sensing signals and the pacing signals between said groups of electrodes and said cardiac pacing device.

A cardiac pacing system comprising:

• a cardiac lead having a distal end including a plurality of electrodes adaptable to be implanted within a heart and a proximal end having plurality of lead terminals, each lead terminal being connected to one of said electrodes;
• a cardiac stimulation device capable of receiving and functioning with a less number of electrodes than the electrodes in said lead;
• and
• an adapter connected between said cardiac lead and said cardiac stimulation device, said adapter including:
• a first connector that mates with said terminals;
• a multiplexer having an input connected to said first connector, a selector connected to said input to chose a group of electrodes, and an output;
• and
• a second connector compatible with and connected to said cardiac stimulation device;
• and
• being connected to said output to transfer said sensing signals and said stimulation signals between the chosen group of electrodes and the cardiac stimulation device.

A cardiac pacing system comprising:

• a cardiac lead having a distal end including a plurality of implantable electrodes and a proximal end having plurality of lead terminals, each lead terminal being connected to one electrode;
• a cardiac pacing device adapted to function with less cardiac electrodes than the number of electrodes in said lead;
• and
• an adapter connected between said lead and said cardiac pacing device, said adapter including:
• a first connector that mates with said lead terminals;
• a sensing multiplexer having a sense input connected to said first connector, a sense selector connected to said sense input to chose a first group of electrodes from said plurality of electrodes, and a sense output to transfer sensing signals and signals from said first group of electrodes;
• a pace multiplexer having a pace input connected to said first connector, a pace selector connected to said pace input to chose a second group of electrodes from said plurality of electrodes, and a pace output to transfer pacing signals to said second group of electrodes;
• a second connector having contacts and being connected to said cardiac pacing device and said pace output to transfer said pacing signals between said groups of electrodes and said cardiac pacing device;
• a sense control circuit connected to said first multiplexer and said contacts to sense an absence of a pacing pulse from said cardiac pacing device to activate said first multiplexer to connect said first group of electrodes to said second connector such that said cardiac pacing device can sense intrinsic cardiac activity;
• and
• a pace control circuit connected to said second multiplexer and said contacts of the second connector to sense the presence of said pacing pulse to deactivate said first multiplexer and activate said second multiplexer to connect said second group of electrodes to said contacts to allow said pacing pulse to be applied to said second group of electrodes.

A method for selecting electrodes of a cardiac lead to be connected to input contacts of a cardiac stimulation device comprising the steps of:

• placing the cardiac lead in contact with a patient's heart;
• designating a sense electrode from said electrodes;
• designating a pace electrode from said electrodes;
• programming an adapter to connect the designated electrodes to the cardiac pacing device;
• and
• connecting said adapter to said cardiac pacing device and said lead.

A cardiac stimulation system comprising:

• a plurality of electrodes adapted to contact a patient's heart;
• an implantable cardiac stimulating device adapted to sense intrinsic cardiac activity in a patient's heart and to generate stimulation pulses corresponding to said intrinsic cardiac activity;
• and
• an adapter connected to said plurality of electrodes and said cardiac stimulating device, said adapter being constructed and arranged to selectively couple a subset of said plurality of electrodes to said cardiac stimulating device to allow said cardiac stimulating device to sense said cardiac activity and to apply said stimulating pulses.