FIG. 9:  What about periodic breathing in patients with HFrEF? This Figure references the same data set from the SchlaHF registry, where PSG was not performed; rather, periodic breathing was assessed with a validated automatic pattern recognition algorithm using the ApneaLink device (ResMed).^[1]  This pattern recognition algorithm reports information for: cycle length, the shape of the ventilatory phase, the shape of the beginning of the ventilatory phase, the apnea lengths, and the length of the ventilation phase. 

As reported by Weinreich et al,^[2] patients with HFrEF and OSA may also have a periodic breathing pattern, which in the clinical setting is usually associated with CSA in physicians’ minds, but when assessed objectively with an automatic algorithm, this periodicity also appears in OSA, although the prevalence of a periodic breathing pattern is higher in patients with predominant CSA.