Characteristics of sleep structure in patients with idiopathic pulmonary arterial hypertension

doi:10.3969/j.issn.1672-5301.2017.07.015

Abstract：Objective To investigate the characteristics of sleep structure in patients with idiopathic pul-monary hypertension (IPAH) and the correlation between the right heart function. Methods 15 female patients with idiopathic pulmonary hypertension were selected in February to June, 2015. Patients were evaluated with right cardiac catheterization, pulmonary function, polysomnograph (PSG), 6 minutes walking test (6MWT) and arterial blood gas was analyzed. 20 female healthy women were selected as the control group. Results ⑴The apnea hy-ponea index (AHI) in patients with IPAH was (1.2±2.2)events/h, control group was (0.3±0.5)events/h, there were not significantly different from the normal control group (P>0.05). ⑵The low oxygen saturation (LSpO2) in patients was (86.40±4.2)%, mean oxygen saturation (MSpO2) was (90.51±3.4)%, the cumulative time of pulse oxygen saturation less than 90% of total sleep time (%TRT SpO2<90%)was (36.67±38.3)%, and in the control group those parameters were(93.14±3.3)%,(97.33±0.5)% and(0.03±0.1)% respectively. There were significant-ly different from normal control group(P<0.05). ⑶There was significant difference in the MSpO2 and LSpO2 at non rapid eye movement sleep stage (NREM) N1, N2, N3 between two groups (P<0.05). ⑷The average respiratory frequency of N2 and N3 stage was negative correlated with cardiac output (CO)(t=-0.652,-0.657, P<0.05), LSpO2 was negative correlated with CO and cardiac index (CI)(t=-0.413, -0.346, P<0.05). Conclusion The sleep structure of patients with idiopathic pulmonary arterial hypertension is normal, and there is no sleep disor-dered breathing, but there is a significant nocturnal hypoxia. There is a close relationship between nocturnal hypox-ia and progressive development of pulmonary hypertension and right ventricular dysfunction.