Extraction of Response Waveforms of Heartbeat and Blood Pressure to Swallowing Using Mixed Signal Processing of Time Domain and Respiratory Phase Domain
Extraction of Response Waveforms of Heartbeat and Blood Pressure to Swallowing Using Mixed Signal Processing of Time Domain and Respiratory Phase Domain
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DOI：
10.3414/me14-01-0050
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发表时间：
2015-01-01
影响因子：
1.7
通讯作者：
Jimbo, Y.
中科院分区：
文献类型：
--
作者：
Numata, T.;Ogawa, Y.;Jimbo, Y.
背景：评估心血管系统对外界刺激的准确反应对于加深对心血管内稳态的理解很重要。目的：提出一种基于时间域和呼吸相域的混合信号处理方法，以提取心率和血压对外界刺激的响应波形，阐明吞咽对心血管系统影响的生理机制。方法：对12名健康受试者在坐姿和站姿下进行测量，要求每个受试者在呼气至吸气之间每隔30分钟吞咽一次S。提取呼吸性窦性心律失常(RSA)波形和与呼吸相关的血压变化作为呼吸时相的函数。结果：吞咽诱发心动过速，在3 S时达到高峰，8 S时恢复，坐位时心动过速明显大于站立时。收缩压、脉压即刻下降，舒张压升高，与心动过速的发生相一致。结论：吞咽诱发的心动过速主要是由于迷走神经活动减少所致，压力感受器反射在恢复过程中可产生快速的振荡反应。
Background: Evaluating the accurate responses of the cardiovascular system to external stimuli is important for a deeper understanding of cardiovascular homeostasis. However, the responses should be distorted by the conventional time domain analysis when a frequency of the effect of external stimuli matches that of intrinsic fluctuations.Objectives: The purpose of this study is to propose a mixed signal processing of time domain and respiratory phase domain to extract the response waveforms of heartbeat and blood pressure (BP) to external stimuli and to clarify the physiological mechanisms of swallowing effects on the cardiovascular system.Methods: Measurements were conducted on 12 healthy humans in the sitting and standing positions, with each subject requested to swallow every 30 s between expiration and inspiration. Waveforms of respiratory sinus arrhythmia (RSA) and respiratory-related BP variations were extracted as functions of the respiratory phase. Then, respiratory effects were subtracted from response waveforms with reference to the respiratory phase in the time domain.Results: As a result, swallowing induced tachycardia, which peaked within 3 s and recovered within 8 s. Tachycardia was greater in the sitting position than during standing. Furthermore, systolic BP and pulse pressure immediately decreased and diastolic BP increased coincident with the occurrence of tachycardia. Subsequently, systolic BP and pulse pressure recovered faster than the R-R interval.Conclusions: We conclude that swallowing-induced tachycardia arises largely from the decrease of vagal activity and the baroreflex would yield fast oscillatory responses in recovery.