Combination of device-detected heart failure status and sleep-disordered breathing for the prediction of atrial fibrillation occurrence

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. AIMS: Patients with atrial fibrillation (AF) frequently experience sleep disorder breathing, and both conditions are highly prevalent in presence of heart failure (HF). We explored the association between sleep apnea (SA) and the HF status and the incidence of AF in patients with implantable defibrillators (ICD). METHODS: Data were prospectively collected from 411 consecutive HF patients with ICD. The HF status was measured by the multisensor HeartLogic Index, and the ICD-measured Respiratory Disturbance Index (RDI) was computed to identify severe SA. The endpoints were: daily AF burden of ≥5minutes, ≥6hours and ≥23hours. RESULTS: During a median follow-up of 26 months, the time IN-alert HF state was 13% of the total observation period, according to the HeartLogic algorithm (Index >16). The RDI value was ≥30 episodes/h (severe SA) during 58% of the observation period. An AF burden of ≥5 minutes/day was documented in 139 (34%) patients, ≥6 hours/day in 89 (22%) patients, and ≥23 hours/day in 68 (17%) patients. The IN-alert HF state was independently associated with AF regardless of the daily burden threshold: hazard ratios from 2.17 for ≥5 min/day to 3.43 for ≥23 h/day (p<0.01). The occurrence of severe SA was associated only with AF burden ≥5 min/day (hazard ratio 1.55 [95%CI:1.11-2.16], p=0.001). The combination of HF alert and severe SA accounted for only 6% of the follow-up period and was associated with high rates of AF occurrence (from 28 events/100 patient-years for AF burden≥5 min/day to 22 events/100 patient-years for AF burden≥23 h/day). CONCLUSIONS: In patients with heart failure (HF) and implantable defibrillators (ICD), the occurrence of atrial fibrillation (AF) was independently associated with the worsened HF status measured by a multisensor ICD algorithm and with ICD-diagnosed severe sleep apnea (SA). The HF status was independently associated with AF regardless of the daily burden, while severe SA was mainly associated with shorter AF episodes. The coexistence of these two conditions occurs rarely but is associated with a very high rate of AF occurrence. [Figure: see text] [Figure: see text]