Phrenic Nerve Simulation for Central Sleep Apnea is Effective and Safe in the Presence of Concomitant Cardiac Devices

Abstract

Introduction Central sleep apnea (CSA) is common in patients with heart failure. Many of these patients also have cardiac implantable electronic devices (CIED). The remedē® System is an implantable neurostimulator for CSA which transvenously stimulates the phrenic nerve to contract the diaphragm, restoring a normal breathing pattern and improving sleep, oxygenation and quality of life. In the remedē System Pivotal Trial, 44% (64/151) of patients had a prior CIED at the time of phrenic nerve stimulation (PNS) implant. Interaction testing was conducted at implant and therapy initiation (1 month post implant). Hypothesis PNS for the treatment of CSA is effective and safe in patients with a prior CIED. Methods Implant metrics, sleep metrics and related serious adverse events (AE) were compared based on the presence or absence of a CIED in patients enrolled in the remedē System Pivotal Trial. Results Of 64 subjects with a CIED, 33 (52%) had an ICD, 20 (31%) CRT-D, 10 (16%) PM, and 1 (2%) CRT-P. Implant metrics: remedē System implant time (2.7 ± 0.8 hours with vs 2.7 ± 0.9 hours without), fluoroscopy time (42 ± 22 min with vs 44 ± 23 min without) and contrast used (57 ± 51 cc with vs. 59 ± 59 cc without) were similar with or without CIED. Successful placement of a left-sided lead for PNS was similar with and without CIED (60% (38/64) vs. 67% (58/87)) as were improvements in central apnea index (-25.7 ± 18.0 events/hour with vs -19.8 ± 17.9 events/hour without) and oxygen desaturation ≥4% index (-23.4 ± 15.7 events/hour with vs -20.9 ± 19.2 events/hour without). Related serious AE through 24 months were lower in the CIED group overall with 8 events reported in 6 (9%) patients compared to 13 events in 11 (13%) patients in the group without CIED. The only event more prevalent in the CIED group was concomitant device interaction, with 4 CIED oversensing events reported in 3 patients resulting in the delivery of ICD therapy in 2 patients (1 shock, 1 anti-tachycardia pacing). Device interactions could be resolved by re-programming the PNS System in all patients without need for surgical revision. Improved concomitant device interaction testing procedures are part of device training and product labeling. Conclusion Phrenic nerve stimulation can effectively and safely treat CSA in patient with a CIED. Rare device interactions could be handled by reprogramming.