Multimodality imaging of aortic dimensions: comparison of transthoracic echocardiography with multidetector row computed tomography.

ABSTRACT

BACKGROUND: With recent advances in multimodality cardiac imaging, a number of methods exist for the noninvasive assessment of aortic disease. Although multidetector row computed tomography (MDCT) remains the gold standard for aortic measurements, there are a number of limitations including radiation and contrast-induced nephropathy. Transthoracic echocardiography (TTE) is an alternative to MDCT for providing accurate anatomic assessment of aortic root and ascending aorta dimensions. OBJECTIVES AND METHODS: To determine the accuracy of two-dimensional (2D) TTE for determining aortic measurements in comparison to MDCT, a retrospective study of individuals with varying aortic root and ascending aorta dimensions was performed. RESULTS: There were 116 patients (77 males, mean age 49 ± 12 years) in total. The maximum aortic diameters by 2D TTE were 26.1 ± 4.3 mm (annulus), 32.4 ± 5.6 mm (sinuses), 30.1 ± 5.9 mm (sinotubular [ST] junction), and 33.4 ± 7.3 mm (ascending aorta). The maximum aortic diameters by MDCT were 30.1 ± 4.1 mm (annulus), 35.8 ± 5.8 mm (sinuses), 33.2 ± 5.9 mm (ST junction), and 37.4 ± 7.6 mm (ascending aorta). There was good to excellent correlation between 2D TTE and MDCT at all four levels of the aorta (annulus r = 0.84; sinuses r = 0.93; ST junction r = 0.93; ascending aorta r = 0.88). There was a consistent underestimation of aortic measurements obtained by 2D TTE when compared to MDCT. CONCLUSION: 2DTTE is a feasible, accurate, and reproducible method for the noninvasive assessment of thoracic aortic diameters as compared to MDCT.