The variability and burden of severe sleep apnea and the relationship with atrial fibrillation occurrence: analysis of pacemaker-detected sleep apnea.

STUDY OBJECTIVES

This was a pilot study to evaluate the long-term variability and burden of respiratory disturbance index (RDI) detected by pacemaker and to investigate the relationship between RDI and atrial fibrillation (AF) event in patients with pacemakers.

METHODS

This was a prospective study enrolling patients implanted with a pacemaker that could calculate the night-to-night RDI. The mean follow-up was 348 ± 34 days. The RDI variability was defined as the standard deviation of RDI (RDI-SD). RDI burden was referred to as the percentage of nights with RDI ≥ 26. The patient with RDI ≥ 26 in more than 75% nights was considered to have a high sleep apnea (SA) burden. An AF event was defined as a daily AF duration > 6 h.

RESULTS

Among 30 patients, the mean RDI of the whole follow-up period was 24.5 ± 8.6. Nine (30%) patients were diagnosed with high SA burden. Patients with high SA burden had a higher BMI (26.7 ± 4.8 vs 23.2 ± 3.9, p = 0.036), a higher prevalence of hypertension (86% vs 39%, p = 0.031), and a larger left ventricular diastolic diameter (49.2 mm vs 46.7 mm, p = 0.036). The RDI-SD in patients with a higher burden was significantly greater than that in the patients with less burden (10.7 ± 4.9 vs 5.7 ± 1.4, p = 0.036). Linear regression showed that participants with a higher RDI tended to have a higher SD (R = 0.661; p < 0.001). The mean RDI (OR = 1.118, 95%CI 1.008-1.244, p = 0.044) was associated with AF occurrence.

CONCLUSION

Using a metric such as burden of severe SA may be more appropriate to demonstrate a patient's true disease burden.