Novel approach to artefact detection and the definition of normal ranges of segmental strain and strain-rate values
AuthorKornev, Mikhail; Caglayan, Hatice Aklay; Kudryavtsev, Alexander V; Malyutina, Sofia; Ryabikov, Andrew; Stylidis, Michael; Schirmer, Henrik; Rosner, Assami
Methods - The study included echocardiograms from men and women aged 40–69 years from two population-based studies, namely the Know Your Heart study (Russia) and the Tromsø Study (Norway). Of the 2207 individuals from these studies, 840 had normal results, defined as the absence of hypertension or indicators of any cardiovascular disease. Two-dimensional (2D) global and segmental S/SR of the three myocardial layers were analysed using speckle tracking echocardiography. Artefacts were assessed with two different methods: visual identification of image-artefacts and a novel conceptual approach of ‘curve-artefacts’ or unphysiological strain-curve formation.
Results - Segmental strain values were found to have significantly reduced in the presence of strain-curve artefacts (14.9%±5.8% towards −20.7%±4.9%), and increased with the foreshortening of the 2D image. However, the individual global strain values were not substantially altered by discarding segmental artefacts. Reduction due to artefacts was observed in all segments, layers, systolic and diastolic strain, and SR. Thus, we presented normal ranges for basal-septal, basal, medial and apical segment groups after excluding artefacts.
Conclusion - Strain-curve artefacts introduce systematic errors, resulting in reduced segmental S/SR values. In terms of artefact-robust global longitudinal strain, the detection of curve-artefacts is crucial for the correct interpretation of segmental S/SR patterns. Intersegmental S/SR gradients and artefacts need to be considered for the correct definition of normalcy and pathology.