Volumetric imaging of fast mechanical waves in the heart using a clinical ultrasound system

The detection and quantification of fast myocardial waves, such as the ones following mechanical activation and aortic valve closure (AVC), may reveal important clinical information about both systolic and diastolic cardiac function. Such waves have previously been observed using multiple high frame rate (HFR) 2-D recordings. However, making multiple 2D recordings lengthens the data acquisition process. Moreover, heart rate variability in combination with the short-lived nature of the studied events makes temporal alignment of these multiple 2D recordings challenging. Fast volumetric imaging would mitigate both problems. However, clinical matrix arrays hinder the straightforward implementation of diverging waves (DW), due to sub-aperture processing (SAP). In this paper, a 3×3 DW sequence implemented on a clinical system using a transesophageal echocardiographic SAP-based matrix array has been validated in-vitro. Subsequently, ultrafast 3D tissue Doppler, strain rate and tissue acceleration were recorded for 4 healthy volunteers at 610 vol/s and used to characterize fast myocardial events. Early myocardial ejection shortening was found in the basal and mid septal wall, as well as in the basal inferior wall. In the septal wall, its propagation was measured as 1.1±0.1 m/s. The wave following AVC was seen traveling both laterally and towards the apex at 4.2±1.0 m/s. These findings seem in agreement with previous reports based on 2D HFR imaging, therefore corroborating the suitability of the 3×3 DW sequence to detect fast myocardial events in 3D within a single heartbeat in a clinical setting.

ISBN:9781538633830

Jaar van publicatie:2017

BOF-keylabel:ja

IOF-keylabel:ja

Authors from:Higher Education

Toegankelijkheid:Closed