Mandibular Advancement Devices Prevent the Adverse Cardiac Effects of Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS)

Chunyan Liu,Haiyan Lu,Wenjing Kang,Xing Qiao,Zheng Zhou,Shilong Zhang,Xiuchun Yang

doi:10.1038/s41598-020-60034-1

Abstract

Although considerable research highlights the interactions between obstructive sleep apnea-hypopnea syndrome (OSAHS) and cardiovascular diseases, the effect of mandibular advancement device (MAD) treatment on cardiovascular complications in OSAHS patients remains unclear. We evaluated the effect of OSAHS treatment with MADs on the myocardium. All methods in this study were in accordance with relevant guidelines and regulations of the medical ethics committee in Hospital of Stomatology, Hebei Medical University approved the work. Thirty New Zealand rabbits were randomized into three groups: the control group, Group OSAHS, and Group MAD. Hydrophilic polyacrylamide gel was injected into the soft palate of the rabbits to induce OSAHS. In Group MAD, a MAD was positioned after OSAHS induction. All animals were induced to sleep in a supine position for 4–6 h/day for 8 weeks. Echocardiography was used to determine the structure and function of the heart. The histological changes were detected by optical microscopy and transmission electron microscopy (TEM). The levels of ET-1(endothelin-1) and Ang II (Angiotensin II) in the plasma were measured by an enzyme-linked immunosorbent assay (ELISA). The expression of ET-1 mRNA in heart tissue was detected by RT-PCR. Histological abnormalities, left ventricular hypertrophy, and left ventricular dysfunctions were demonstrated in Group OSAHS, and the abnormities were rescued with MAD treatment. Higher levels of plasma ET-1 and Ang II and elevated expression of ET-1 mRNA in cardiac tissue were detected in Group OSAHS compared with Group MAD and the control group. The blood oxygen saturation was negatively correlated with the levels of ET-1 and Ang II. OSAHS-induced elevated levels of ET-1 and Ang II may be attributed to myocardial structural abnormalities and dysfunction. Early treatment of MADs may play an important role in preventing myocardial damage in OSAHS rabbit model.

Highlights

This finding suggested that obstructive sleep apnea-hypopnea syndrome (OSAHS) was successfully induced by palatal gel injection and that mandibular advancement device (MAD) were effective in alleviating the OSAHS-like symptoms in this study
It was shown that there was a significant increase in apnea-hypopnea index (AHI) and a decrease in SaO2 in Group OSAHS (p < 0.05) by PSG, but there were no significant differences in AHI and SaO2 between Group MAD and the control group (p > 0.05) (Fig. 2)
Nasal airflow decreased when apnea or hypoxia appeared, with an associated increase in respiratory effort in Group OSAHS. These results suggest that the OSAHS model was successfully induced and that MAD fabrication was feasible and effective

Summary

Introduction

We aimed to investigate the changes of cardiac structure and function in the rabbit OSAHS model developed in our laboratory[26,27] and to determine the effects of OSAHS on cardiac structure and function and the role of MADs in the remedies of possible injuries. This will provide evidence for the clinical treatment of OSAHS with MADs and further explore the possible mechanism of these changes

Objectives

Methods

Results

Conclusion