Myocardial Tissue Characterization in Echocardiography with Videodensitometry: Evaluation of a New Semi-automatic Software Applied on a Population of Hypertensive Patients

BACKGROUND: The interactions between ultrasound and cardiac muscle can be exploited to characterize abnormalities of myocardial structure in echocardiography. Two different methods permit an objective assessment of myocardial tissue characterization: analysis of the radiofrequency signal and videodensitometry. We conducted a videodensitometric study using a new practical semi-automatic software applied on digital signal to evaluate gray level cyclic variations of myocardial walls. The aim was to determine parameters differentiating healthy and hypertrophic myocardium in hypertensive patients. METHODS AND RESULTS: Echocardiographic examinations were performed on 30 hypertensives vs 30 healthy controls using second harmonic imaging. Dynamic 2D sequences were recorded in digital form and transferred on computer. Region of interest (ROI) was selected on interventricular septum (IVS) and the software automatically analyzed its systolo-diastolic displacements. ROI echo intensity and its cyclic variations were computed. Values were normalized with blood backscatter. The hypertensives had a smaller amplitude of gray level cyclic variation than did the controls (22+/-6 vs 27+/-11; P=0.02), and this parameter was correlated in multivariate analysis with left ventricle fractional shortening (P=0.032) and diastolic pressure(P=0.014). CONCLUSIONS: Magnitude of gray level cyclic variation of IVS can be studied easily with this new semi-automatic software, is altered in hypertensives and correlated with parameters of systolic function.