Spectral analysis of systolic blood pressure in atrial fibrillation
Arai, H.; Sato, H.; Yamamoto, M.; Kirigaya, H.; Aizawa, T.; Fu, L-Tai.
Journal of Cardiology 41(5): 235-239
2003
ISSN/ISBN: 0914-5087 PMID: 12795113 Document Number: 552550
Power spectral analysis was used to analyze fluctuations of systolic blood pressure and heart rate. Non-invasive finger plethysmography and electrocardiography were performed in 20 patients with chronic atrial fibrillation and in 10 age-matched healthy subjects with normal sinus rhythm. The impulse train was stored on a personal computer and the power spectrum of R-R interval and systolic blood pressure were obtained by Fourier analysis (0.01-0.03 Hz). The power spectrum (log power vs log frequency) characteristically revealed a linear regression as 1/f beta. The R-R interval spectrum during atrial fibrillation showed a white noise-like flat spectrum when plotted as log power against log frequency, whereas the systolic blood pressure spectrum during atrial fibrillation showed a 1/f noise-like negative slope linear pattern. The spectrum exponent of systolic blood pressure in patients with atrial fibrillation was significantly lower than that in subjects with normal sinus rhythm (2.3 +/- 0.1 vs 1.3 +/- 0.1, p < 0.0001). Systolic blood pressure fluctuation in patients with atrial fibrillation has a fractal component and is more complex than that of healthy subjects with normal sinus rhythm.