Abstract 238: Aortic Intima-Media Thickness by M-mode or 2-Dimensional Semi-Automated Imaging: Do These Methods Provide Equivalent Results?
Background Aortic (Ao) atherosclerosis is best defined by manual quantitation of intima-media thickness (IMT) using M-mode. However, M-mode imaging is time consuming and requires experience. Thus, we aimed to determine if Ao IMT assessed by M-mode and 2-dimensional (2-D) semi-automated imaging provide similar results.
Methods 57 volunteer subjects (51 women, age 36±12 years) underwent multiplane transesophageal echocardiography (TEE) using a 7 MHz phased array transducer with a 0.1 mm axial resolution. At low depth (3-4cm) and with a narrow sector scan to improve image resolution, 2-D guided M-mode images were obtained to assess IMT of the anterior wall of the proximal, mid, and distal descending thoracic Ao. At each Ao level, 3 IMT measurements were performed from Ao long axis views during end-diastole. Studies were measured off-line using electronic calipers by an experienced observer. A second observer unaware of M-mode results and using 2-D semi-automated imaging performed Ao IMT measurements from long axis images at each Ao level and same site where M-mode measurements were obtained.
Results IMT of proximal, mid, and distal Ao by M-mode was similar to that obtained by 2-D semi-automated imaging (p≥0.19) (Table). Less variability of IMT values occurred by 2-D than by M-mode imaging (coefficient of variation 17% vs 38%). Both imaging methods were highly correlated (overall r=0.69, p<0.001).
Conclusion Assessment of Ao IMT by TEE M-mode and 2-D semi-automated imaging provide equivalent results.
- © 2013 by American Heart Association, Inc.