Holmqvist Fredrik, Stridh Martin, Waktare Johan E P, Brandt Johan, Sörnmo Leif, Roijer Anders, Meurling Carl J
Department of Cardiology, Lund Univ. Hospital, SE-221 85 Lund, Sweden.
Am J Physiol Heart Circ Physiol. 2005 Aug;289(2):H754-60. doi: 10.1152/ajpheart.00075.2005.
Heart rate during sinus rhythm is modulated through the autonomic nervous system, which generates short-term oscillations. The high-frequency components in these oscillations are associated with respiration, causing sinus arrhythmia, mediated by the parasympathetic nervous system. In this study, we evaluated whether slow, controlled respiration causes cyclic fluctuations in the frequency of the fibrillating atria. Eight patients (four women; median age 63 yr, range 53-68 yr) with chronic atrial fibrillation (AF) and third-degree atrioventricular block treated by permanent pacemaker were studied. ECG was recorded during baseline rest, during 0.125-Hz frequency controlled respiration, and finally during controlled respiration after full vagal blockade. We calculated fibrillatory frequency using frequency analysis of the fibrillatory ECG for overlapping 2.5-s segments; spectral analysis of the resulting frequency trend was performed to determine the spectrum of variations of fibrillatory frequency. Normalized spectral power at respiration frequency increased significantly during controlled respiration from 1.4 (0.76-2.0) (median and range) at baseline to 2.7 (1.2-5.8) (P = 0.01). After vagal blockade, the power at respiration frequency decreased to 1.2 (0.23-2.8) (P = 0.01). Controlled respiration causes cyclic fluctuations in the AF frequency in patients with long-duration AF. This phenomenon seems to be related to parasympathetic modulations of the AF refractory period.
窦性心律时的心率通过自主神经系统进行调节，自主神经系统会产生短期振荡。这些振荡中的高频成分与呼吸相关，导致窦性心律失常，由副交感神经系统介导。在本研究中，我们评估了缓慢、有控制的呼吸是否会导致颤动心房的频率出现周期性波动。对8例（4例女性；年龄中位数63岁，范围53 - 68岁）患有慢性心房颤动（AF）且接受永久性起搏器治疗的三度房室传导阻滞患者进行了研究。在基线静息状态下、0.125赫兹频率控制呼吸期间以及最后在完全迷走神经阻滞后的控制呼吸期间记录心电图。我们使用对颤动心电图的2.5秒重叠段进行频率分析来计算颤动频率；对所得频率趋势进行频谱分析以确定颤动频率变化的频谱。在控制呼吸期间，呼吸频率的归一化频谱功率从基线时的1.4（0.76 - 2.0）（中位数和范围）显著增加至2.7（1.2 - 5.8）（P = 0.01）。迷走神经阻滞后，呼吸频率的功率降至1.2（0.23 - 2.8）（P = 0.01）。有控制的呼吸会导致长期房颤患者的房颤频率出现周期性波动。这种现象似乎与房颤不应期的副交感神经调节有关。
