Non-invasive estimation of left ventricular myocardial fiber stress by using subclavian artery pulse tracings and M-mode echocardiography

Myocardial fiber stress is important when assessing LV function hypertrophy and oxygen demand. Non-invasive estimation of muscle fiber stress may be done by utilizing subclavian pulse traces and M-mode Echocardiography. The authors have developed a formula for fiber stress based on chamber dimensions that are easy to obtain by Echocardiography (wall thickness, diameter and long axis length). In addition, they have developed analysis software for estimation of fiber stress. To obtain normal values, they have examined 10 subjects. The normal values for start ejection stress, peak stress and end ejection stress were 37.1+/-9.0, 51.2 +/-17.9 and 27.8+/-8.4 kPa, respectively (mean+/-2SD). The methodology is promising. However, to determine the clinical usefulness of this method the authors also have to obtain normal values in subjects with cardiac diseases related to pressure or volume overload of the left ventricle