Related Experiment Video
Updated: Aug 4, 2026

Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves
Published on: October 17, 2013
Digital acoustical analysis of normal and bimodal Björk-Shiley 60 degrees convexo-concave heart valves
G A Kien1, B Jeffries, H V Katz
1International Acoustics Incorporated, Palatine, Illinois.
Abstract:
Fracture of the outlet strut of the Björk-Shiley 60 degrees convexo-concave (BS60CC) valve has been attributed to a bimodal closing pattern in certain valves in which the closing disk rotates about the inlet strut, causing upward displacement of the outlet strut and its eventual fracture. This article reports the in vivo studies of the normal BS60CC valve and the in vitro studies of the normal and bimodal BS60CC valves, using a digital acoustical signal processing technique, in which the individual collisions (impact history) of the occluder disk with the components of the valve body are revealed during each closing cycle. In vitro analysis of the closing acoustical signals of normal BS60CC valves showed impact history cluster width (IHCW) means of 2.07 +/- 0.85 ms (standard error), not significantly different from those of 1.86 +/- 0.58 ms (standard error) observed in 38 clinically normal patients with BS60CC valves (p greater than 0.1). The bimodal valves showed IHCW of 6.14 +/- 0.98 ms (standard error), in vitro, which was significantly greater than those observed in the normal in vitro valve group and in the normal patient population (p less than 0.0001).
Related Concept Videos
Heart Valves
The AV valves prevent the backflow of blood from the ventricles to the atria during ventricular contraction. These valves function with the assistance of the chordae tendineae and papillary muscles. When the ventricles are relaxed, the chordae tendineae are slack, allowing blood to flow from the atria into the...
Assessment of the Cardiovascular System IV: Auscultation
Normal Heart Sounds
S1 (First Heart Sound)-
S1 is made by the closure of the mitral and tricuspid valves (atrioventricular valves), marking the beginning of systole.
S2 (Second Heart Sound)-
S2 is made by the closure of the aortic and pulmonic valves (semilunar valves), marking the end of the systole.
Cardiovascular System Abnormal Findings II: Auscultation
Abnormal Heart Sounds
Gallops:
Mitral Valve Prolapse I: Introduction
Mitral Valve Prolapse II: Assessment and Management
Mitral Regurgitation I: Introduction

