Implanted Phrenic Stimulation Impairs Local Diaphragm Myofiber Reinnervation in Amyotrophic Lateral Sclerosis

Diaphragm pacing through laparoscopically implanted intramuscular electrodes led to significant excess mortality in two recent randomized controlled trials in amyotrophic lateral sclerosis (ALS). DiPALS (Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis) and RespiStimALS (Early Diaphragm Pacing in Patients with Amyotrophic Uteral Sclerosis). In the RespiSlimALS study, the decrease in survival observed with active stimulation was associated with an accelerated deterioration of lung function. With the pacing technology used in RespiStimALS, termination of phrenic nerves is stimulated by the diffusion of electrical current through the adjacent diaphragm muscle mass.