Apparatus and method for making electrical connections in an implantable pacemaker

A pacemaker connector assembly for detachably, electrically connecting first and second spaced-apart electrodes of a proximal end of a pacemaker lead to first and second terminals of an implantable pacemaker, the pacemaker connector assembly comprising:

• a nonconductive entrance connector having a channel therethrough for receiving the proximal end of the pacemaker lead therethrough, the entrance connector further having a conductive tube molded therein;
• a nonconductive body ring having a channel therethrough for receiving the proximal end of the pacemaker lead therethrough, the body ring having a groove for receiving the conductive tube, the body ring including engagement means for joining the entrance connector at one end of the body ring, the body ring further having a first access window therethrough for making electrical contact with the conductive tube;
• a nonconductive body tip having a recess for receiving a proximal end of the pacemaker lead therein, the body tip having a connector block molded therein, the connector block including means for receiving the first electrode of the pacemaker lead, the body tip having a second access window therethrough for making electrical contact with the connector block, the body tip further including an annular lip protruding from the body tip which is sized for a press-fit to the other end of the body ring;
• a garter spring contact sized to fit inside the conductive tube, the garter spring contact comprising an electrically conductive material;
• and
• means for making respective electrical contact from the connector block and the conductive tube to the first and second pacemaker terminals by way of the first and second access windows, respectively;
• whereby the first and second spaced apart electrodes of the pacemaker lead may be inserted into the body tip and body ring so as to make respective electrical contact with the block electrode and the garter spring contact;
• whereby electrical contact is made between the first and second electrodes of the pacemaker lead and the first and second pacemaker terminals, respectively.

A pacemaker header assembly for detachably, electrically connecting a proximal tip and ring electrode of a proximal end of a pacemaker lead to first and second terminals of an implantable pacemaker, the pacemaker header assembly comprising:

• a molded body tip having a recess for receiving the proximal end of the pacemaker lead therein, the body tip including a first conductive means insert molded so as to form an integral part thereof, the first conductive means having means for making electrical contact with the proximal tip electrode;
• a molded entrance connector having a channel for receiving the proximal end of the pacemaker lead therethrough, the entrance connector including a second conductive means insert molded so as to form an integral part thereof, the second conductive means having means for making electrical contact with the proximal ring electrode;
• a molded body ring having a channel for receiving the proximal end of the pacemaker lead therethrough, the body ring including engagement means for joining the entrance connector to one end of the body ring and for joining the body tip to the other end of the body ring;
• means for making electrical contact from the first and second conductive means to the first second pacemaker terminals, respectively;
• and
• means for housing the molded body tip, the molded entrance connector, the molded body ring, and the contact means in a biocompatible material.

A method of making electrical connections between the proximal end of an implantable lead and the electrical circuits within a sealed housing of an implantable medical device, the housing having a first feedthrough terminal therethrough, the method comprising the steps of:

• making a first nonconductive connector, the first connector including a cavity therein for receiving a proximal tip electrode of a implantable lead, the first connector further including a conductive terminal for making electrical contact with the proximal tip electrode of the implantable lead;
• making a second nonconductive connector, the second connector including a channel for passing the proximal end of the implantable lead therethrough, the second connector further including a first recess;
• making a third nonconductive connector, the third connector including a channel for passing the proximal end of the implantable lead therethrough, the third connector further including a second recess;
• making a first and a second sealing ring;
• inserting the first sealing ring into the first recess of the second connector;
• inserting the second sealing ring into the second recess of the third connector;
• joining the first, second and third connectors together;
• connecting a first conductor at one end to the first feedthrough terminal and at the other end to the conductive terminal, the first, second and third connector, including the conductive terminal, forming a connector subassembly;
• and
• casting the connector subassembly in a body compatible material onto the housing.