Videodensitometric measurements in contrast-echocardiology

Describes a technique for studying global and regional motion patterns of the right ventricle (RV) using contrast echocardiography in conjunction with videodensitometric measurements. Two ml of echo-contrast (Haemaccel, Behring/Hoechst) was injected as a bolus into a brachial vein. An image sequence visualizing the RV echocontrast filling and elimination was analysed in real-time. The mean image intensity of predefined regions of interest (ROI) at the inflow tract and apex was computed over time. This signal was modelled by two exponentials which time constants were used for discriminating between a group of healthy subjects and patients with arrythmogenic right ventricular dysplasia (ARVD). The ARVD patients had delayed filling and elimination rates in the RV apex region as compared to the controls (p<0.05). Also, for the ARVD patients, the filling rate was lower in the apex region as compared to the inflow tract (p<0.001). In addition to ROI echo-contrast analysis, time-of-arrival and time-of-departure maps were developed. These maps show the overall ventricular-filling and elimination patterns as well as their timings. It was concluded that contrast-echocardiography with real-time video densiometry can be an effective means for studying right ventricular function.