We`ve introduced the regional endocardial length shortening rate to assess the regional wall motion quantitatively and more accurately, presented the normal value and effectiveness in detecting regional wall motion abnormalities.
By definition, the early phases of ischemic heart diseases result in regional wall motion abnormalities. So it's very important to assess regional wall motion quantitatively for diagnosing heart diseases, estimating the effectiveness of treatment and prognosis.
First of all, we've defined the regional endocardial length shortening rate (RELSR) and established the automatic quantitative evaluation system.
After giving 10 min rest to the patient, we recorded the parasternal short-axis views of echocardiograph for 2~3 beats at mitral valve, papillary muscle and apical level. We determined the endocardial contours at diastole and systole. Then we set the boundary points of segments on the diastolic contour according to the 16-segment model for left ventricular segmentation, and tracked them automatically during contraction. We defined the length of segments produced on the systolic and diastolic contours by these points as the regional endocardial length (REL), and calculated the RELSR of each segment by the formula as follows
[(REL at diastole – REL at systole) / REL at diastole]×100(%)
Involving 118 of healthy subjects (10~60 years old) and 31 patients with acute myocardial infarction diagnosed at Pyongyang Medical College Hospital of
Basing on the normal value, we assessed the regional wall motion of the patient's segment as being normal, hypokinetic, or dyskinetic by X-2SD and 0. (X: Mean of normal value in each segment, SD: standard deviation of normal value in each segment)
The sensitivity and specificity of RELSR analysis in detecting regional wall motion abnormalities is 98.19% and 93.82%, respectively.
The result of the study shows that the regional wall motion can be assessed quantitatively by our suggestion so that we can diagnose the ischemic heart diseases and estimate the effectiveness of treatment more accurately.
