Improved in vitro quantification of the force exerted by the papillary muscle on the left ventricular wall: Three-dimensional force vector measurement system

Recent developments indicate that the forces acting on the papillary muscle s can be a measure of the severity of mitral valve regurgitation. Pathologi cal conditions, such as ischemic heart disease, cause changes in the geomet ry of the left ventricle and the mitral valve annulus, often resulting in d isplacement of the papillary muscles relative to the annulus. This can lead to increased tension in the chordae tendineae. This increased tension is t ransferred to the leaflets, and can disturb the coaptation pattern of the m itral valve. The force balance on the individual components governs the fun ction of the mitral valve. The ability to measure changes in the force dist ribution from normal to pathological conditions may give insight into the m echanisms of mitral valve insufficiency. A unique in vitro model has been d eveloped that allows quantification of the papillary muscle spatial positio n and quantification of the three-dimensional force vector applied to the l eft ventricular wall by the papillary muscles. This system allows for the q uantification of the global force exerted on the posterior left ventricular wall from the papillary muscles during simulation of normal and diseased c onditions. (C) 2001 Biomedical Engineering Society.