Cardiac pacing

Abstract

A cardiac pacing system that includes an implantable pulse generator and electrical leads that include a lead body portion having a distal end and a proximal end, a connector configured to electrically connect the proximal end of the lead body to the pulse generator, and at least one electrode disposed at the distal end of the lead body for delivering electrical stimulation to a patient's heart, wherein the distal end of the lead body is configured to terminate within the mediastinum of the thoracic cavity of the patient, proximate to the heart.

What is claimed is: 
     
         1 . A system comprising:
 a pulse generator including a housing, the pulse generator configured to generate therapeutic electric pulses;   at least one lead configured to electrically couple with the pulse generator and transmit the therapeutic electric pulses generated by the pulse generator, the lead including an electrical impedance detector configured to monitor the electrical impedance of tissue proximate to a distal end of the lead; and   a controller configured to determine a location of the distal end of the lead based on the electrical impedance.   
     
     
         2 . The system of  claim 1 , wherein the electrical impedance detector is at the distal end of the lead. 
     
     
         3 . The system of  claim 1 , the controller further configured to compare the electrical impedance of the tissue with known electrical impedance of tissues stored in computer memory to determine the location of the distal end of the lead. 
     
     
         4 . The system of  claim 1 , the controller further configured to compare the electrical impedance of the tissue with known electrical impedance of tissues stored in computer memory to detect a transition of the distal end of the lead between tissue planes. 
     
     
         5 . The system of  claim 1 , the controller further configured to compare the electrical impedance of the tissue with known electrical impedance of tissues stored in computer memory to detect a type of tissue proximate the distal end of the lead. 
     
     
         6 . A system comprising:
 a pulse generator including a housing, the pulse generator configured to generate therapeutic electric pulses;   at least one lead configured to electrically couple with the pulse generator and transmit the therapeutic electric pulses generated by the pulse generator, the lead including a sensor configured to monitor electrical energy generated by the heart and/or other anatomical structures;   at least one programmable processor; and   a controller configured to determine a location of a distal end of the lead based at least on the electrical energy detected by the sensor.   
     
     
         7 . The system of  claim 6 , the controller further configured to compare the electrical energy detected by the sensor with a model in order to determine the location of the distal end of the lead. 
     
     
         8 . The system of  claim 6 , the controller further configured to identify advancement into a different tissue plane based on a sudden change in the electrical energy detected by the sensor.