(33).
Three-dimensional speckle tracking echocardiography is an advanced echo
imaging technique that is postulated to provide a comprehensive
assessment of LV function with additional advantaged over 2D imaging(34), i.e. simultaneous speckle
tracking in more than one direction allowing for assessment of
longitudinal, circumferential and radial strain simultaneously, and
requirement for a single apical acquisition, which in turn, may make
assessment of LV strain more time efficient and thus more applicable in
a busy clinical setting (34).The utility of 3D-LVS has been demonstrated in several pathologies
including ischemic heart disease, cardio-oncology, valvular heart
disease, left ventricular hypertrophy hence certainly applicable for
myocarditis. Furthermore, 3D-LVS has successfully been used to identify
subclinical LV dysfunction (35),and shown to be non-inferior to 2D STE in patients with aortic stenosis(36). Of the included studies,
one study did demonstrate that patients with acute myocarditis in
comparison to controls had lower 3D LV-GLS values. This study also
highlighted that there was a good correlation between 2D- and 3D- GLS
measurements in this study (r=0.84, p<0.01). These findings
are also in keeping with pooled results on 2D LV-GLS from the
meta-analysis in our study. Nonetheless, 3D-STE is still currently used
primarily in the research settings and not in routine clinical practice
given its high image and operator dependency. Some of the disadvantages
of 3D STE which may still serve as barriers for application in routine
clinical use, include the requirements for a stable regular heart rhythm
during image acquisition and analysis, optimal LV images and with good
temporal resolution and a high frame rate. Nonetheless, 3D-LVS may still
have a useful role in the diagnostic work-up in myocarditis