New insights into the 120-year-old Korotkoff sound, which would reflect artery stiffness and more cardiovascular diseases

Korotkoff sound generation remains controversial, limiting its physiological interpretation and clinical application. In this cross-sectional observational study, we developed a biomechanical model that couples an arterial wall spring-mass-damper system with Womersley-based blood flow, in which wall motion alters cross-sectional area and flow-related forces excite vibration. Korotkoff sounds were also recorded in 98 participants, including controls and patients with elevated arterial stiffness, hypertension, heart failure, aortic stenosis, or aortic regurgitation. All five pathological groups showed significant differences from controls in selected acoustic features. Cardiac abnormalities were associated with greater low-frequency spectral content, whereas hypertension and elevated arterial stiffness showed distinct amplitude-related characteristics. After calibration, the model showed significant agreement with the clinical data at the level of selected spectral features. These findings provide feature-level mechanistic support linking disease-related cardiovascular alterations to Korotkoff sound variation.