Methods and apparatus for express estimation of the arterial elastic property in a subject

A system for assessing arterial elasticity, comprising:

• a non-transitory, computer readable memory;
• one or more processors;
• and
• a computer-readable medium containing programming instructions that, when executed by the one or more processors, cause the system to:
• impose a rhythmical stimulation to cause an oscillation on the cardiovascular system of a subject, wherein the rhythmical stimulation is induced by causing the subject to perform a paced sighing at a pacing frequency of about 0.066 Hz or about 0.081 Hz;
• measure each of the paced sighing beat-to-beat intervals and PTT responses that are associated with the oscillation on the cardiovascular system of the subject caused by the rhythmical stimulation;
• generate a frequency spectrum for the measured beat-to-beat intervals and PTT responses;
• and
• determine an arterial elasticity of the subject by determining heart rate variability (HRV) based on amplitudes of the beat-to-beat intervals and PTT responses associated with the oscillation at the pacing frequency in the frequency spectrum.