心率变异性在妊娠期疾病中的应用研究进展
2018-05-08朱美琳郑文慧程莉莉董有静
朱美琳 郑文慧 程莉莉 董有静
[摘要] 妊娠期母体特殊的生理及心理变化会导致某些疾病的发生,如妊娠期高血压,妊娠期糖尿病、妊娠期睡眠呼吸暂停综合征等。妊娠期疾病的发生发展与妊娠期母体自主神经功能的变化密切相关,如先兆子痫产妇的极低频功率与低频功率(LF)显著升高;妊娠期糖尿病产妇夜间的高频功率(HF)下降明显;妊娠期睡眠呼吸综合征患者LF/HF升高;先天性心脏病产妇的24 h连续正常RR间期的标准差、HF和LF明显降低;心律失常产妇的心率变异性变化存在争议。心率变异性可通过安全无创手段监测自主神经的变化,对评价及预测妊娠期母体系统病变有重要的临床价值。
[关键词] 心率变异性;频域分析;时域分析;妊娠期高血压疾病;妊娠期糖尿病;妊娠期睡眠呼吸暂停综合征
[中图分类号] R714.2 [文献标识码] A [文章编号] 1673-7210(2018)02(c)-0031-04
Research progress in application of heart rate variability in pregnancy disease
ZHU Meilin ZHENG Wenhui CHENG Lili DONG Youjing
Department of Anesthesiology, Shengjing Hospital of China Medical University, Liaoning Province, Shenyang 110000, China
[Abstract] Particular physical and psychological changes in the maternal body during pregnancy can lead to the occurrence of certain diseases, such as gestational hypertension, gestational diabetes, gestational sleep apnea syndrome, etc. The development of pregnancy disease is closely related to the change of maternal autonomic nervous function during pregnancy, for example, the very low frequency (VLF) and low frequency (LF) of pregnant women with preeclampsia increased significantly. The high frequency (HF) of pregnant women with gestational diabetes decreased significantly at night. The LF/HF of pregnant women with sleep apnea syndrome increased. The 24 hours standard deviation of NN intervals, HF and LF of the patients with congenital heart disease were significantly decreased, and the Heart rate variability (HRV) variation of the mothers with arrhythmia was controversial. HRV connected by safe noninvasive means can monitor the change of autonomic nerve and it has important clinical value in the evaluation and prediction of pregnancy maternal system disease.
[Key words] Heart rate variability; Frequency domain analysis; Time domain analysis; Gestational hypertension; Gestational diabetes; Gestational sleep apnea syndrome
心率變异性(heart rate variability,HRV)是指心电图中的RR间期变异性,反映心率连续波动的瞬时变化。由于其产生于自主神经系统对心脏窦房结的调节作用,故可以作为反映心脏自主神经系统平衡的指标,并为评估交感和副交感神经系统的状况及二者的相互作用提供参考。HRV监测手段安全无创,在反映心脏自主神经系统和外周压力感受器调节的灵敏度方面要高于血压、心率等指标[1-2]。因此,HRV不仅在评价及预测妊娠期母体自主神经功能状态上得到广泛应用,而且在评价相关妊娠期疾病的临床作用方面也日益受到人们的关注。
1 HRV的分析方法
HRV分析方法主要包括:频域分析、时域分析、频谱分析、几何分析和非线性分析。另外,压力反射敏感性和心率紊乱度也可以作为HRV的分析方法。频域分析和时域分析在临床上的应用较为广泛。
1.1 频域分析
频域分析多用做短程研究,其指标包括:①反映交感和迷走神经的双重活性的低频功率(LF);②反映迷走神经功能状态的高频功率(HF);③反映心脏交感和迷走神经张力平衡状况的LF/HF;④反映自主神经受血管舒缩张力影响的极低频功率(VLF);⑤反映自主神经的总功率。
1.2 时域分析
通过分析一段时期内相邻RR间期的变异性,利用各种统计方法得出一系列时域统计指标进行时域分析。指标包括:①24 h连续正常RR间期的标准差(SDNN);②24 h内连续5 min平均R-R间期的标准差;③相邻 RR 间期相差>50 ms的个数(NN50);④NN50计数占总RR间期数的百分比;⑤全程相邻RR间期之差的均方根(rMSSD)。
2 妊娠期母体HRV变化
大量研究表明,妊娠期母体在自主神经系统的变化比较显著,已经证实正常产妇妊娠期与非妊娠时期相比,HRV出现明显抑制。Carpenter等[3]认为,从孕早期开始,母体的自主神经功能就开始出现变化。他们的实验通过检测QT间期变异率以及HRV,发现从孕早期开始母体就呈现出交感神经张力增加而迷走神经张力下降的趋势,即LF/HF升高的趋势。同样,也有研究证实,妊娠期LF/HF的升高主要发生在妊娠前6个月[4]。然而,也有一些研究者得到不同的结论,在整个孕期反应交感与迷走平衡的指标LF/HF没有显著变化,孕晚期产妇会发生较明显HRV削减,这可能与孕晚期巨大的子宫对下腔静脉的压迫有关[5]。
3 妊娠合并系统疾病与HRV
3.1 妊娠合并高血压疾病与HRV
妊娠合并高血压疾病是造成围生期母胎死亡的重要因素,在全球范围内,妊高症的发病率已经高达5%~10%[6],其发病机制尚未完全明确。有研究者称,在妊娠期交感神经占据明显优势,而在妊娠期高血压疾病的患者中这种优势更加明显[7-8]。有日本学者认为,亚洲人群中妊娠期高血压疾病的发生率低于白种人,原因在于白种人自主神经系统中交感优势更明显[9]。Hossen[10]利用了频域分析方法成功地区分了先兆子痫产妇与健康产妇,先兆子痫产妇VLF与LF显著升高。Lakhno等[11-12]研究发现,与健康产妇相比,先兆子痫的产妇SDNN和PNN 50明显降低,表明先兆子痫产妇自主神经功能存在不同程度损伤,提示合理的HRV监测可以帮助实现妊娠期高血压疾病的早发现早治疗。
3.2 妊娠期糖尿病与HRV
妊娠期糖尿病(gestational diabetes mellitus,GDM)是2型糖尿病的重要危险因素,目前已经证实2型糖尿病患者的自主神经功能存在不同程度损伤,且其LF/HF较健康人群升高。国外研究对比了GDM产妇与健康产妇夜间的HRV,结果显示,GDM产妇HF较健康产妇明显下降,而LF/HF变化却并不明显[13],提示GDM患者并非呈现出交感优势的状态,可能与GDM患者与2型糖尿病患者的自主神经受损程度不同有关[14-15]。上述研究同时发现,血清中儿茶酚胺的浓度与VLF 、LF及HF成分呈负相关。也有研究指出,妊娠期血糖的升高并未使产妇的HRV出现明显变化,反而使胎儿的SDNN、LF和HF出现一过性下降[16]。尽管如此,仍有学者提出HRV的减少可以成为更好的GDM预测指标,可见监测围生期HRV的变化可用于GDM的预测以及临床干预[17]。
3.3 妊娠期睡眠呼吸暂停综合征与HRV
受妊娠期肥胖以及高龄妊娠的影响,妊娠期睡眠呼吸暂停综合征(obstructive sleep apnoea,OSA)的发生率逐渐升高。一项涵盖了105名孕妇的队列研究发现,在孕早期与孕晚期OSA的发生率分别为10.5%和26.7%[18]。妊娠期OSA可导致包括巨大儿、先兆子痫及宫内迟缓发育等一系列母婴不良反应。研究表明,妊娠期OSA造成的慢性间歇性缺氧会形成机体内的氧化应激反应,使交感神经的张力升高、压力感受器敏感性下降,使产妇LF/HF升高[18-19]。在重度OSA人群中,清醒期的LF/HF与血氧饱和度呈负相关[19]。而国外学者的研究通过更详尽的睡眠研究表明了妊娠期OSA的患者在清醒期LF/HF升高,而在快动眼睡眠期则呈现HRV下降的趋势,这可能与OSA患者睡眠期自主神经功能下降造成的LF下降有关[20]。由此也可以解释年龄作为OSA的重要影响因素的作用机制,与年轻患者相比,高龄患者OSA的发生率较高,自主神经功能下降,睡眠期HRV能量下降,从HRV的角度阐释了高龄妊娠的一定风险。
3.4 先天性心脏病合并妊娠与HRV
正常产妇妊娠期心率有增快趋势,而在大多妊娠合并先天性心脏病的产妇中,由于内源性传导障碍、血流动力学不稳定以及长期服用药物等因素,使得心率增快、心律失常的发生更加普遍[21]。有报道称,合并先天性心脏病的产妇较正常产妇SDNN、HF与LF明显减低[22],提示自主神经功能的损害可能是先天性心脏病产妇妊娠期心血管意外发生的重要始动因子。在妊娠合并先天性心脏病的患者中,HRV的实时监测可以提供较为准确的心脏自主神经功能的评价,进而为临床指导用药、评估病情进展以及为确定终止妊娠的时机提供证据[23]。
3.5 心律失常与HRV
妊娠期间新发心律失常风险较高,可能与孕期自主神经功能及血流动力学稳态的改变有关。围术期心律失常发生率更高,一项针对254名进行剖宫产手术的健康产妇的研究表明,约13%的产妇可发生围术期心律失常[24]。有学者认为HRV的改变是引起妊娠期恶性心律失常及猝死的主要因素[25]。進入孕晚期,自主神经对窦房结的调控功能减弱,QT间期缩短,心率加快,对应HRV能量降低,进而增加围生期心律失常的风险。也有研究者得出的结论认为LF/HF的升高是围生期快速型心律失常的重要危险因素[26]。最终结论有待进一步的实验证实。
3.6 其他妊娠期不良事件与HRV
在一项针对习惯性流产的人群自主神经功能的研究中,LF/HF的升高提示母体交感迷走调节紊乱与不良妊娠有着紧密联系。也有人研究产妇紧张程度与HRV的关系,妊娠期间适当的心理干预可以稳定自主神经系统,降低心血管意外的发生率,增加自然生产的概率[27]。除此之外,高风险妊娠胎儿的HRV分析可以很好地反映胎儿自主神经的发育状况[28-29],但母体HRV与胎儿HRV的相互联系还有待大量实验佐证。
4 展望
综上所述,HRV作为一种新型监测自主神经功能的无创技术,在妊娠期特殊的生理状态中有着日益广泛的应用。期待HRV监测技术的完善与普及,为临床工作者判断自主神经系统功能与疾病的发生、发展和预后带来更大的帮助。
[參考文献]
[1] Vaseghi M,Shivkumar K. The role of the autonomic nervous system in sudden cardiac death [J]. ProgCardiovasc Dis,2008,50(6):404-419.
[2] Ozkececi G,Dursun H,Akoi O,et al. Heart rate variability and heart rate turbulence in patients with polycystic ovary syndrome [J]. Anatol J Cardiol,2016,16(5):323-327.
[3] Carpenter RE,Emery SJ,Uzun O,et al. Changes in heart rate variability and QT variability during the first trimester of pregnancy [J]. Physiol Meas,2015,36(3):531-545.
[4] Stein PK,Hagley MT,Cole PL,et al. Changes in 24-hour heart rate variability during normal pregnancy [J]. Am J Obstet Gynecol,1999,180(4):978-985.
[5] Maser RE,Lenhard MJ,Kolm P. Autonomic modulation in gestational diabetes mellitus [J]. J Diabetes Complications,2014,28(5):684-688.
[6] Malik R,Kumar V. Hypertension in pregnancy [J]. Adv Exp Med Biol,2017,956(2):375-393.
[7] Jarvis SS,Shibata S,Bivens TB,et al. Sympathetic activation during early pregnancy in humans [J]. J Physiol,2012, 590(15):3535-3543.
[8] Flood P,McKinley P,Monk C,et al. Beat-to-beat heart rate and blood pressure variability and hypertensive disease inPregnancy [J]. Am J Perinatol,2015,32(11):1050-1058.
[9] Okada Y,Best SA,Jarvis SS,et al. Asian women have attenuated sympathetic activation but enhanced renal-adrenal responses during pregnancy compared to Caucasian women [J]. J Physiol,2015,593(5):1159-1168.
[10] Hossen A,Barhoum A,Jaju D,et al. Identification of patients with preeclampsia from normal subjects using wavelet-based spectral analysis of heart rate variability [J]. Tec?鄄hnol Health Care,2017,25(4):1-9.
[11] Lakhno I. Autonomic imbalance captures maternal and fetal circulatory response to pre-eclampsia [J]. Clin Hyper?鄄tens,2017,23(1):5.
[12] Murphy MS,Seaborn GE,Redfearn DP,et al. Reduced Heart Rate Variability and Altered Cardiac Conduction after Pre-Eclampsia [J]. PLoS One,2015,10(9):1-11.
[13] Poyhonen-Alho M,Viitasalo M,Nicholls MG,et al. Imba?鄄lance of the autonomic nervous system at night in women with gestational diabetes [J]. Diabet Med,2010,27(9):988-994.
[14] Shaltout HA,Rose JC,Chappell MC,et al. Angiotensin-(1-7)deficiency and baroreflex impairment precede the antenatal Betamethasone exposure-induced elevation in blood pressure [J]. Hypertension,2012,59(2):453-458.
[15] Patey N,Seely AJ,Faure C,et al. Can Monitoring Fetal Intestinal Inflammation Using Heart Rate Variability Analysis Signal Incipient Necrotizing Enterocolitis of the Neonate [J]. Pediatr Crit Care Med,2016,17(4):165-176.
[16] Fehlert E,Willmann K,Fritsche L,et al. Gestational diabetes alters the fetal heart rate variability during an oral glucose tolerance test:a fetal magnetocardiographystudy [J]. BJOG,2016,13(4):335-343.
[17] Scholte AJ,Schuijf JD,Delgado V,et al. Cardiac autonomic neuropathy in patients with diabetes and no symptoms of coronaryartery disease:comparison of 123I-metai?鄄odobenzylguanidine myocardial scintigraphy and heart rate variability [J]. Eur J Nucl Med Mol Imaging,2010, 37(9):1698-1705.
[18] Pien GW,Pack AI,Jackson N,et al. Risk factors for sleep-disordered breathing in pregnancy [J]. Thorax,2014,69(4): 371-377.
[19] Idiaquez J,Santos I,Santin J,et al. Neurobehavioral and autonomic alterations in adults with obstructive sleep apnea [J]. Sleep Med,2014,15(11):1319-1323.
[20] Trimer R,Cabidu R,Sampaio LL,et al. Heart rate variability and cardiorespiratory coupling in obstructive sleep apnea:elderly compared with young [J]. Sleep Med,2014, 15(11):1324-1331.
[21] Aydin E,Ozyuncu O,Kasapoglu D,et al. Clinical analyses of 383 cases with maternal cardiac diseases [J]. J Per?鄄inat Med,2017,17(3):122-128.
[22] Niwa K,Tateno S,Akagi T,et al. Arrhythmia and reduced heart rate variability during pregnancy in women with congenital heart disease and previous reparative surgery [J]. Int J Cardiol,2007,122(2):143-148.
[23] Jelinek HF,Adam MT,Krones R,et al. Diagnostic Accuracy of Random ECG in Primary Care for Early,Asymptomatic Cardiac Autonomic Neuropathy [J]. Diabetes Sci Technol,2017:59(2):763-771.
[24] Shen CL,Ho YY,Hung YC,et al. Arrhythmias during spinal anesthesia for Cesarean section [J]. Can J Anaesth,2000, 47(5):393-397.
[25] Nolte IM,Munoz ML,Tragante V,et al. Genetic loci associated with heart rate variability and their effects on cardiac disease risk [J]. Nat Commun,2017,8:1580-1585.
[26] Franciosi S,Perry FKG,Roston TM,et al. The role of the autonomic nervous system in arrhythmias and sudden cardiac death [J]. Auton Neurosci,2017,205(4):1-11.
[27] Muthukrishnan S,Jain R,Kohli S,et al. Effect of Mindfulness Meditation on Perceived Stress Scores and Autonomic Function Tests of Pregnant Indian Women [J]. J Clin Diagn Res,2016,10(4):1-10.
[28] Moslem B,Mohydeen A,Bazzi O. Monitoring the fetal heart rate variability during labor [J]. Conf Proc IEEE Eng Med Biol Soc,2015:5846-5850.
[29] Verdurmen KM,Eijsvoogel NB,Lempersz C,et al. A systematic review of prenatal screening for congenital heart disease by fetal electrocardiography.Verdurmen [J]. Int J Gynaecol Obstet,2016,135(2):129-134.
(收稿日期:2017-10-29 本文編辑:王 娟)