Computerized system for the assessment of left ventricular function based on ventricular dimensions and intracardiac pressure measurements

• Main Authors: Hnatkova, K., Varma, C., Waktare, J.E.P., Brecker, S.J., Malik, M.
• Format: Conference Proceeding
• Language: English
• Subjects: Biomedical imaging; Catheters; Color; Echocardiography; Hospitals; Morphology; Motion estimation; Pressure measurement; Signal resolution; Testing
• ISSN: 0276-6547
• DOI: 10.1109/CIC.1999.825988

A computer system to calculate left ventricular (LV) cavity dimension (LVD) from M-mode echocardiography, and LV pressure (LVP) from micromanometer tipped catheter simultaneously was developed. An operator marked the LV posterior wall and septal endocardial borders, the LVP tracing, and reference points on a scanned bitmap image of the echocardiogram and LVP trace. Individual lines were automatically recognized in the bitmap, values at individual points were recalculated and missing data interpolated. The time functions of LVD and LVP were constructed. Signal averaging of cardiac cycles was used to increase the resolution of both functions. Characteristics of LVP and LVD functions were calculated, such as pressure dimension loops, their cycle efficiency, dLVD/dt, dLVP/dt, etc. In total, 25 bitmap echocardiographic images were tested. 8% images required readjustment of operator marking. Of 92% processed images, reliable values and morphologies of cycle efficiency loops were obtained in 83% of tracings. Mean value of 67.7/spl plusmn/13.2% of cycle efficiency was noted. Thus, this system offers a possibility to derive the LV cycle efficiency as well as other LV functional parameters precisely and with a restricted manual involvement.