The purpose of this study was to compare the accuracy of vendor-specific and independent strain analysis tools to detect regional myocardial function abnormality in a clinical setting.
Background
Speckle tracking echocardiography has been considered a promising tool for the quantitative assessment of regional myocardial function. However, the potential differences among speckle tracking software with regard to their accuracy in identifying regional abnormality has not been studied extensively.
Methods
Sixty-three subjects (5 healthy volunteers and 58 patients) were examined with 7 different ultrasound machines during 5 days. All patients had experienced a previous myocardial infarction, which was characterized by cardiac magnetic resonance with late gadolinium enhancement. Segmental peak systolic (PS), end-systolic (ES) and post-systolic strain (PSS) measurements were obtained with 6 vendor-specific software tools and 2 independent strain analysis tools. Strain parameters were compared between fully scarred and scar-free segments. Receiver-operating characteristic curves testing the ability of strain parameters and derived indexes to discriminate between these segments were compared among vendors.
Results
The average strain values calculated for normal segments ranged from −15.1% to −20.7% for PS, −14.9% to −20.6% for ES, and −16.1% to −21.4% for PSS. Significantly lower values of strain (p < 0.05) were found in segments with transmural scar by all vendors, with values ranging from −7.4% to −11.1% for PS, −7.7% to −10.8% for ES, and −10.5% to −14.3% for PSS. Accuracy in identifying transmural scar ranged from acceptable to excellent (area under the curve 0.74 to 0.83 for PS and ES and 0.70 to 0.78 for PSS). Significant differences were found among vendors (p < 0.05). All vendors had a significantly lower accuracy to detect scars in the basal segments compared with scars in the apex (p < 0.05).
Conclusions
The accuracy of identifying regional abnormality differs significantly among vendors.
Dr. Mirea is permanently affiliated to the Department of Cardiology, University Hospital of Craiova, Romania. This study was supported by a dedicated grant from the American Society of Echocardiography. Dr. Mirea has received a research grant from the European Association of Cardiovascular Imaging. Dr. Pagourelias holds a research grant from the European Association of Cardiovascular Imaging. Dr. Thomas has received honoraria and consulting fees from Edwards Lifesciences, Abbott, and GE. Dr. Voigt holds a personal research mandate from the Flemish Research Foundation; and has received a research grant from the University Hospital Gasthuisberg. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
