High-Frame-Rate Tri-Plane Echocardiography using a Dense 512-element Matrix Array

Many cardiac diseases, amongst which arrhythmias, are associated with left ventricular (LV) dysfunction, which can be assessed using echocardiography. With the advent of high-frame-rate (HFR) imaging, the high temporal resolution facilitates the detection of the onset of myocardial deformation and can therefore be a useful tool to localize the source of arrhythmias. It has been demonstrated that subsequent 2D HFR recordings taken from the apical view in order to cover the whole LV can be effective in the localization of arrhythmia source. However, this approach requires multiple recordings which takes time and can be affected by heart rate variability. To address this, we propose to automate and synchronize the acquisition of HFR tri-plane images, improving both efficiency and efficacy for clinicians. In this study, we propose and test different sequences including: seven diverging waves (DWs) and 12 DWs with coherent compounding, 12 DWs with sliding window coherent (SWC) compounding, and single line transmit (SLT) as a benchmark. These are deployed using a dense 3.0 MHz, 512-element matrix array. The resulting tri-plane images are evaluated by measuring the resolution of wire targets. The sliding-window coherent compounding with the transmission of 12 DWs in a triangular sequence proves to be optimal, with an average axial and lateral resolution of 0.96 and 2.17 mm respectively and a high frame rate of 1332 Hz.