Persistence of the diastolic Korotkoff sound

Diastolic Korotkoff sounds have been shown to often appear well below actual diastolic pressures, leading to a large error in pressure readings. The curvilinear brachial artery pressure-lumen relationship was examined as a possible source of sound generation. A sinusoidal pressure was applied in both a mathematical model and an experimental model. It was found that increasing pulse pressure at mean transmural pressures approaching zero led to significant sound generation. It is concluded that the process of arterial collapse can lead to diastolic Korotkoff sound even under zero flow conditions.