Evaluation of Central and Reflex Cardiovascular Control By Beat-to-Beat Analysis of the 24 Hour Blood Pressure Signal in Man

Abstract

In man neural control of circulation has been mainly studied via laboratory manoeuvars devised to alter in a controlled fashion central and reflex influences on the heart and the systemic blood vessels. However, techniques are now available to monitor 24 hour intra-arterial blood pressure and pulse interval in ambulant subjects (1) thereby studying the involvement of neural factors in cardiovascular modulation in daily life. This paper will deal with this issue to reach the following conclusions: 1) circulation is normally under powerful central influences which are probably responsible for a large fraction of the 24 hour blood pressure and heart rate variability characterizing human beings 2) however, blood pressure and heart rate variabilities are also modulated by negative feed-back mechanisms, i.e. by the arterial baroreflex which play a role in determining the magnitude of these phenomena and 3) this role can be examined in detail by new methods of analysis of the beat- to-beat blood pressure signal.

Key Words:

• Baroreflex
• Beat-to-Beat a nalysis
• Blood Pressure
• Pulse rate