Contribution of arterial tree structure to the arterial pressure fractal behavior
نویسندگان
چکیده
Arterial vascular beds can be characterized considering the arterial segments in terms of their physical properties. These and other trees have an open structure based on repeated bifurcations, following fractal rules. Fractal dimension (FD) quantifies the time series complexity defined by its geometrical representation. Objective: To evaluate the arterial pressure and diameter time series in order to assess the influence of arterial tree structure in arterial pressure fractal dimension (FD). Methods: Simultaneous aortic pressure and diameter were measured in 14 conscious dogs. A pair of ultrasonic crystals, a pressure microtransducer and a pneumatic cuff occluder were positioned in the upper third of the descending aorta. Results: Total reflection induced by the occlusion maneuver decreased FD concomitant to the aortic stiffening and early wave reflection. Conclusion: Arterial pressure fractality is highly dependent on the arterial tree structure.
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