Sleep Apnea, Atrial Fibrillation Identified in Patients with Heart Failure

Giuseppe Boriani MD, PhD

An implantable cardioverter defibrillator (ICD) algorithm identified severe sleep apnea in heart failure patients and concluded that they were two- to three-fold more likely to experience an atrial fibrillation (AF) episode.

Sleep disordered breathing is frequently cited in patients with heart failure due to multiple factors included hypoxemia, sympathetic activation and systematic inflammation related to obstructive sleep apnea.

Modern pacemakers and ICD have been equipped with algorithms based on the continuous measurement of thoracic impedance in order to detect advanced sleep apnea.

In the present study, an investigative team led by Giuseppe Boriani, MD, PhD, University of Modena and Reggio Emilia, performed an analysis of the Diagnosis of Sleep Apnea in Patient with HF (DASAP-HF) study to investigate the association between AF and ICD-detected sleep apnea.

The study was a prospective, non-randomized multi-center evaluation of patients implanted with an ICD or cardiac resynchonization therapy ICD endowed with the ApneaScan™ diagnostic feature.

Eligible patients had to present with current ICD or CRT-D indication with left ventricular systolic dysfunction, and devices and pacing leads were implanted by means of standard techniques.

Baseline evaluation consisted of demographics and medical history, clinical examination, 12-lead electrocardiogram, and echocardiographic evaluation.

Meanwhile, the sleep study consisted of unattended home nocturnal recordings via sleep apnea monitors with multiple sensors. Sleep apnea was defined by the Apnea hypopnea index (AHI) as 30 or less episodes during the sleep-study night.

Following the sleep study, the implanted devices were interrogated, and data were retrieved.

Endpoints for the study included daily AF burden of ≥5 minutes, ≥6 hours, and ≥23 hours.

A total of 164 patients had usable RDI values during the follow-up period. Among them, 92 (56%) patients were diagnosed with severe sleep apnea.

During the follow-up period, AF burden ≥5 minutes/day was documented in 70 (43%) patients, with 48 (29%) patients experienced AF burden of ≥6 hours/day, and 33 (20%) of patients ≥23 hours/day.

A Cox regression model indicated that device-detected RDI≥30 episodes/h at the time of the polygraphy, and the polygraphy-measured apnea hypopnea index ≥30 episodes/h were not associated with the occurrence of the endpoints.

However, continuously measured weekly mean RDI≥30episodes/h was independently associated with AF burden≥5 minutes/day (HR:2.13, 95%CI:1.24-3.65) (P=0.006), ≥6 hours/day (HR:2.75, 95%CI:1.37-5.49) (P=0.004), and ≥23 hours/day(HR:2.26, 95% CI:1.05-4.86) (P=0.037).

“All these data suggest that information on SA and AF burden may integrate the clinical assessment of an individual patients and facilitate resulting in improved decision making,” the team wrote.

The study, "Association between implantable defibrillator-detected sleep apnea and atrial fibrillation: the DASAP-HF study," was published online in the Journal of Cardiovascular Electrophsiology.