Table 3– Respiratory and sleep characteristics according to the change of cardiac function

	Improved left ventricular EF			Unchanged left ventricular EF			p-value
	Baseline	12 weeks	p-value	Baseline	12 weeks	p-value	p-value
Respiratory characteristic
AHI events·h⁻¹	21±14	11±9	0.010	22±26	23±24	0.756	0.036
Obstructive AHI events·h⁻¹	12±10	6±4	0.008	10±10	14±19	0.166	0.009
Central AHI events·h⁻¹	10±12	6±6	0.342	12±23	6±10	0.287	0.906
P_a,CO₂ mmHg	35.2±4.2	37.6±3.6	0.073	35.2±2.2	37.6±3.4	0.002	0.958
Mean S_a,O₂ %	93.4±1.8	94.4±1.4	0.041	93.8±1.9	94.0±1.5	0.398	0.149
S_a,O₂,min	85.0 ±7.9	86.5±6.3	0.546	85.6±6.3	85.4±6.4	0.335	0.471
Sleep characteristic
Sleep efficiency %	76±1	74±1	0.544	70±1	70±1	0.135	0.150
N3 %	16±6	14±6	0.413	17±9	16±10	0.594	0.717
REM %	17±6	15±7	0.394	16±8	14±7	0.097	0.757
ESS	8±5	7±3	0.886	7±4	6±3	0.617	0.821

Data are presented as mean±SD, unless otherwise stated. EF: ejection fraction; AHI: apnoea/hypopnoea index; P_a,CO₂: arterial carbon dioxide tension; S_a,O₂: arterial oxygen saturation; S_a,O₂,min: minimum arterial oxygen saturation; N3: % of total sleep time spent in N3 sleep stage; REM: % of total sleep time spent in rapid eye movement sleep stage, ESS: Epworth Sleepiness Scale score.