The Nature of the Korotkoff Signal and its Application for Blood Pressure Measurement
31 August 1986
Analysis of Korotkoff signals recorded under a sphygmomano- meter cuff by a Foil Electret Sensor, which has a flat frequency response from a below 0.1 Hz to above 2,000 Hz reveals three distinct components, K1, K2, and K3. K1 is present above systolic pressure and coincides with the pressure wave, K2 appears at systolic pressure and disappears at diastolic pressure, K3, similarly to K1, resembles the intra-arterial pressure waveform.