A pilot application of Korotkoff sound delay time in evaluating cardiovascular status.

BACKGROUND Korotkoff sounds have been used to measure systolic and diastolic arterial blood pressures noninvasively for over 100 years. However, most of the research concerning the Korotkoff sound were focused on the origin and frequency component analyzing the Korotkoff sound signal. OBJECTIVE To show that the occurrence time of the Korotkoff sounds for each cardiac cycle demonstrates a characteristic value during the cuff deflating process of blood pressure measurement. METHODS The Korotkoff sound delay time (KDT) decreases as the cuff pressure P deflates and KDT is a function of arterial transmural pressure. In the present research, an experiment system was established to explore the relationship between the KDT and the cuff pressure in different subjects. RESULTS A pilot experiment was conducted to obtain different subjects' KDTs and investigate the relationship between KDT and cuff pressure. CONCLUSION The relationship between KDT and invasive blood pressure was also studied and its potential application in detection of cardiovascular status was discussed.