Stambler B S, Ellenbogen K A
Division of Cardiology, West Roxbury Veterans Affairs Medical Center, MA 02132, USA.
Circulation. 1996 Nov 15;94(10):2515-25. doi: 10.1161/01.cir.94.10.2515.
The mechanism of the small beat-to-beat variations in cycle length of atrial flutter in humans has not been fully explained. We investigated the beat-to-beat control of atrial flutter cycle length using time and frequency analysis techniques.
Mean, SD, and power spectra of atrial cycle lengths were calculated from atrial recordings in 28 patients with type I atrial flutter. In control patients, mean and SD values of atrial cycle length were 265 +/- 37 and 4.9 +/- 1.7 ms. Power spectra contained two or three major peaks with 10.6 +/- 9.2% in band 1 (0.0 to 0.18 Hz), 26.7 +/- 15.9% in band 2 (0.18 to 0.6 Hz), and 63.1 +/- 17.7% in band 3 (0.6 to 2.2 Hz). Isoproterenol infusion (n = 8) increased percentage of total power in band 1 (7.1 +/- 5.6% to 25.7 +/- 18.9%, P < .001). Percentage of total power in band 1 was less in patients receiving (n = 5) versus not receiving (n = 18) oral beta-blockers (2.2 +/- 1.9% versus 10.6 +/- 9.2%, P = .003). Standard deviation (2.5 +/- 1.3 versus 4.9 +/- 1.7 ms, P = .009) and total power (2025 +/- 1350 versus 9768 +/- 8874 ms2, P = .005) were less in heart transplant recipients (n = 5) than control patients. Increases in respiratory rate (n = 6) shifted band 2 frequency peak to higher frequencies (0.26 +/- 0.13 to 0.38 +/- 0.18 Hz, P < .05). Atrial cycle length was longer and monophasic action potential duration was shorter during inspiration than during expiration. Band 3 frequency peak was correlated with heart rate (r = .797, P < .0001).
Atrial flutter cycle length variability has an underlying periodic pattern that is detected by spectral analysis. Atrial flutter is modulated on a beat-to-beat basis by an interplay between the autonomic nervous and respiratory systems and the ventricular rate.
人类心房扑动周期长度逐搏微小变化的机制尚未完全阐明。我们使用时间和频率分析技术研究了心房扑动周期长度的逐搏控制情况。
计算了28例I型心房扑动患者心房记录中的心房周期长度的均值、标准差和功率谱。在对照患者中，心房周期长度的均值和标准差分别为265±37和4.9±1.7毫秒。功率谱包含两到三个主要峰值，频段1（0.0至0.18赫兹）占10.6±9.2%，频段2（0.18至0.6赫兹）占26.7±15.9%，频段3（0.6至2.2赫兹）占63.1±17.7%。静脉输注异丙肾上腺素（n = 8）使频段1中总功率的百分比增加（从7.1±5.6%增至25.7±18.9%，P <.001）。接受（n = 5）与未接受（n = 18）口服β受体阻滞剂的患者相比，频段1中总功率的百分比更低（2.2±1.9%对10.6±9.2%，P =.003）。心脏移植受者（n = 5）的标准差（2.5±1.3对4.9±1.7毫秒，P =.009）和总功率（2025±1350对9768±8874毫秒²，P =.005）低于对照患者。呼吸频率增加（n = 6）使频段2的频率峰值移向更高频率（从0.26±0.13至0.38±0.18赫兹，P <.05）。吸气时心房周期长度更长，单相动作电位持续时间比呼气时更短。频段3的频率峰值与心率相关（r =.797，P <.0001）。
心房扑动周期长度变异性具有潜在的周期性模式，可通过频谱分析检测到。心房扑动在逐搏基础上受自主神经系统、呼吸系统和心室率之间相互作用的调节。
