Method and apparatus for inspiratory muscle stimulation using implantable device

A system for use in a body having left and right phrenic nerves and left and right pericardiophrenic veins, the system comprising:

• an implantable medical device including:
• a respiratory sensor configured to sense a respiratory signal;
• a respiratory cycle detector configured to detect events indicative of respiratory cycles using the respiratory signal, the respiratory cycles indicative of an intrinsic respiratory rate;
• a respiratory performance monitor configured to detect one or more respiratory performance parameters indicative of respiratory performance from the respiratory signal, the one or more respiratory performance parameters including a minute ventilation;
• a stimulation circuit configured to deliver stimulation;
• and
• a stimulation controller coupled to the respiratory cycle detector and the stimulation circuit, the stimulation controller programmed to control the delivery of the stimulation and including a stimulation rate adjuster programmed to cause the stimulation to be delivered at a stimulation rate that is approximately equal to the intrinsic respiratory rate for a period of time allowing the respiratory cycles to be under control of the stimulation and to decrease the stimulation rate after the period of time at a rate allowing the respiratory cycles to adapt to the stimulation rate until the stimulation rate reaches a specified target respiratory rate, the stimulation controller including a stimulation safety switch programmed to inhibit the delivery of the stimulation using the one or more respiratory performance parameters including the minute ventilation.