TRANSVENOUS PHRENIC NERVE STIMULATION IMPACT ON PATIENTS WITH HEART FAILURE AND CENTRAL SLEEP APNEA

Abstract

SESSION TITLE: Sleep Disorders Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Epworth Sleepiness Scale (ESS) is used to screen for subjective excessive daytime time sleepiness (EDS) in obstructive sleep apnea (OSA) but has not been validated to define EDS in patients with heart failure (HF) and central sleep apnea (CSA). Our and other laboratories have shown most patients with HF do not report EDS, yet when tested in laboratory by multiple sleep latency test, many exhibit short sleep latency. We hypothesized an ESS of 10-11, the threshold to define EDS in OSA in the general population, is not appropriate for patients with CSA and HF. In the pivotal randomized controlled trial (RCT) of transvenous phrenic nerve stimulation (TPNS), there were 96 patients with CSA and HF with a wide range (0-21) in ESS, with median=8. In this analysis, we investigated the impact of TPNS on outcomes based on ESS ≥8. METHODS: Outcomes were evaluated for subgroups having baseline ESS≥8 vs. ESS<8 within the Treatment (n=30 and 18, respectively) and Control (implanted but therapy inactive for 6 months, n=24 and 24, respectively) groups. Changes in ESS, sleep metrics and quality of life (QoL) were assessed at 6 months. P-values from exploratory analyses comparing results between TPNS ESS subgroups are reported. RESULTS: TPNS treated patients with ESS≥8 had significantly greater ESS improvement (n=30, median 12 at baseline vs 6.5 at 6 months) than the ESS<8 TPNS subgroup (n =18, 5 vs 5) [p<.01]. There were no significant changes in ESS in the Control subgroups with either ESS≥8 (median 13 at baseline vs 12 at 6 months) or ESS<8 (4 vs 4.5). Comparing the ESS≥8 subgroups, 54% of the TPNS subgroup and 19% of Control shifted to from ≥8 to <8 at 6 months (p=0.03). The median apnea hypopnea index (AHI) decreased from 50 to 20 events/hour in the ESS≥8 subgroup (57% of subjects experienced ≥50% reduction in AHI) and from 43 to 28 in the ESS<8 subgroup (60% had ≥50% reduction in AHI) [p=0.98]; the median AHI in both Control subgroups increased at 6 months and ≤10% reduced AHI by ≥50%. In both TPNS subgroups, the arousal and oxygen desaturation indices also improved significantly from baseline whereas Control had minimal change. The Patient Global Assessment improved markedly or moderately in 63% of the TPNS ESS≥8 subgroup compared to 50% of the <8 subgroup (p=0.52). CONCLUSIONS: The results of this RCT suggest in patients with HF and CSA, TPNS significantly improves sleep metrics and QoL independent of ESS. Additionally, TPNS improves EDS significantly in the subgroup with EDS≥8, suggesting ESS≥8 may be a better threshold defining EDS as it identifies a subgroup of HF patients who may benefit most from TPNS therapy in sleepiness and QoL. Similar data with CPAP or ASV are lacking but could be retrieved from previous RCTs which reported no significant change in EDS. CLINICAL IMPLICATIONS: ESS≥8 best defines EDS in patients with HF and may identify potential CSA candidates who could benefit most from therapy. DISCLOSURES: Employee relationship with Respicardia, Inc. Please note: >$100000 Added 04/13/2020 by Robin Germany, source=Web Response, value=Salary no disclosure on file for Lee Goldberg; Consultant relationship with Respicardia Please note: $20001 - $100000 Added 04/09/2020 by Shahrokh Javaheri, source=Web Response, value=Honoraria Employee relationship with Respicardia Please note: >$100000 Added 04/12/2020 by Scott McKane, source=Web Response, value=Salary Employee relationship with Respicardia Please note: >$100000 Added 04/13/2020 by Timothy Meyer, source=Web Response, value=Salary