Functional myocardial assessment in cine cardiac computerized tomographic angiography using echocardiographic feature-tracking software in patients with and without significant coronary disease

Abstract

Introduction: Cardiac computerized tomographic angiography (CCTA) is perceived as a non-invasive tool for assessment of coronary vessel anatomy. Feature tracking echocardiography has recently emerged as a tool for assessment of regional and global left ventricular function. We aimed to explore the applicability of echocardiographic strain on CCTA cine clips and assess whether global and regional strain parameters are associated with the extent of coronary stenosis. Methods: CCTA studies of 61 consecutive patients were reconstructed to yield cine images in classic echocardiographic long and short views. Siemens Velocity Vector Imaging (VVI) software was applied to generate strain and displacement results. Volumetric and mechanics parameters were compared among patients with no or non-significant coronary artery disease (CAD) and patients with significant CAD. Finally, a comparison of the degree of coronary stenosis to regional segmental strain was performed. Results: Myocardial mechanics parameters could be generated in 60 cases. Ejection fraction (EF) and left ventricular end diastolic volume (LVEDV) were within the normal range in both groups. VVI values were lower in the CAD group (VVI LVEF 59 ± 6 vs. 50 ± 11, p = 0.0002). Global longitudinal and global circumferential strain both were significantly lower in this group. Regional segmental strain was lower in segments affected by coronary stenosis in comparison to unaffected segments. Conclusion: While CT segmentation derived LVEF did not differ among groups, patients with significant coronary stenosis had reduced longitudinal and circumferential contraction. This suggests that application of VVI to CCTA cine clips tracking may help to differentiate significant and non-significant coronary stenosis, adding functional value to anatomic findings in CCTA.

Keywords

• Cardiac computerized tomographic angiography (CCTA)
• Coronary arteries
• Velocity Vector Imaging (VVI)
• Global longitudinal strain (GLS)
• Global circumferential strains (GCS)