Experience With Adaptive Servo-Ventilation Among Veterans in the Post-SERVE-HF Era

Abstract

Background: The sleep medicine community has struggled to identify the ideal role for adaptive servo-ventilation (ASV) therapy following a study that found increased mortality in patients with central sleep apnea (CSA) and heart failure with reduced ejection fraction who used ASV therapy. We aimed to identify characteristics of patients who benefit from ASV therapy.

Methods: We performed a record review of all patients treated with ASV therapy at the Hampton Veterans Affairs Medical Center in Virginia from January 1, 2015, to April 30, 2020. Clinical and polysomnographic characteristics of patients adherent to therapy were compared with those that were not adherent.

Results: Our cohort of 31 patients was entirely male with a mean age of 67.2 years, body mass index of 34.0, and Epworth Sleepiness Scale score of 10.9. Primary CSA was initially diagnosed in 3 patients (10%), comorbid obstructive sleep apnea (OSA) and CSA in 9 (29%), and primary OSA in 19 (61%). Seventeen patients (55%) met minimal adherence criteria with ASV therapy. The obstructive apnea-hypopnea index (AHI), as a proportion of the total pretreatment AHI, was higher in adherent patients (81.5%) vs nonadherent patients (46.7%) (P = .02). The median residual AHI was lower in the adherent group, both as absolute values (1.7 vs 4.7 events/h; P = .004) and as a percentage of the pretreatment AHI (3.1% vs 10.2%; P = .002).

Conclusions: Patients using ASV devices regularly have a larger component of obstructive sleep-disordered breathing and obtain greater objective benefit from ASV than those that do not. This understanding may help to identify patients that will most benefit from this debated form of therapy.

FIGURE 1

Central vs Obstructive Contribution to the Pretreatment AHI Abbreviation: AHI, apnea-hypopnea index.

FIGURE 2

Treatment Effect of Adaptive Servo-Ventilation^{a a}Residual apnea-hypopnea index (events per hour and as the proportion of pretreatment apnea-hypopnea index) P < .01.