Techniques are provided for treating periodic
breathing, such as Cheyne-Stokes
Respiration, using an implantable medical
system. In one technique, diaphragmatic stimulation is delivered during a hyperpnea phase of periodic
breathing via electrical stimulation of the phrenic nerves. Diaphragmatic stimulation is synchronized with intrinsic inspiration so as to increase the amplitude of diaphragmatic contraction during inspiration. This tends to decrease intrathoracic pressure leading to
occlusion of the
respiratory airway.
Occlusion reduces actual ventilation during hyperpnea, thus reducing the cyclic
blood chemistry imbalance that sustains periodic
breathing so as to either mitigate periodic breathing or eliminate it completely. In another technique,
respiration is instead inhibited during the hyperpnea phase of periodic breathing by blocking
phrenic nerve signals to the extent necessary to reduce ventilation to terminate periodic breathing or at least mitigate its severity. Techniques are also described for controlling the type of therapy applied in response to periodic breathing.