[Possibilities and limitations of three-dimensional transesophageal echocardiography in the diagnosis of thoracic aorta atherosclerosis]

Complex aortic plaques: hidden danger in aortic stenosis. Role of transesophageal echocardiography

Aortic stenosis is associated with aortic plaques in up to 85% of cases because they share risk factors and pathogenic pathways. Intrinsically, complex aortic plaques carry a high risk of stroke, which has also been demonstrated in the context of aortic stenosis, especially in patients who underwent percutaneous or surgical replacement. Transesophageal echocardiography (TEE) is the imaging test of choice to detect plaques in the thoracic aorta and classify them as complex plaques. Furthermore, the 3D modality allows us to better specify its dimensions and anatomical characteristics, such as added thrombi or the presence of ulcers inside. This review aims to evaluate the use of TEE to detect complex aortic plaques in patients with an indication for percutaneous or surgical aortic valve replacement. To highlight the association between aortic stenosis and complex aortic plaques, we attached to the review some TEE studies from our experience.

Role of Imaging Modalities in the Quantitative Assessment of Atherosclerotic Plaques in the Thoracic Aorta

AIM

Comparative analysis of the height of atherosclerotic plaques (AP) in the descending thoracic aorta (TA) according to two-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE), and contrast-enhanced multislice computed tomography (MSCT).

MATERIAL AND METHODS

The TA was examined using 2D, 3D TEE and contrast-enhanced MSCT in 34 patients (20 men and 14 women aged 68 [62; 71] years). AP heights were compared using the Bland-Altman method and the Spearman correlation analysis. This was a blinded comparative study which assessed the AP morphometry using each of the radiation modalities without knowing the results of the method being compared.

RESULTS

100 APs were examined in the descending TA. The mean height of all analyzed APs in the descending TA was 2.2 mm [2; 2.7] for 2D TEE, 3.1 mm [2.7; 3.55] for 3D TEE, and 3.05 mm [2.55; 3.55] for MSCT. The AP heights measured with 2D TEE was statistically significantly smaller than the heights of similar APs measured either with 3D TEE or MSCT. The mean difference (bias) was 0.88±0.34 mm between 2D and 3D TEE, and 0.83±0.41 mm between 2D TEE and MSCT. The correlation coefficients for the AP heights were r=0.87 (p<0.001) between 2D and 3D TEE and r=0.86 (p<0.001) between 2D TEE and MSCT. There were no differences in the height of similar APs between 3D TEE and MSCT.

CONCLUSION

The three-dimensional reconstruction of AP in the TA by TEE is more accurate for quantitative assessment of AP than a two-dimensional study.

Structural and Functional Disturbances of the Thoracic Aorta in Atherosclerosis of Various Gradations

Aim      To study global aortic circumferential strain in normal conditions and in atherosclerosis of various grades and to determine its role in prediction of structural and functional disorders of the thoracic aorta (TA) and coronary atherosclerosis using 2D speckle-tracking transesophageal echocardiography.Material and methods  182 patients with typical or probable angina were examined. The control group consisted of 11 healthy volunteers. TA was visualized along its entire length. The height of each atheroma was measured, and the total number of plaques in the TA was determined. Five stages of TA atherosclerosis were identified. In the descending TA, the global peak systolic circumferential strain (GCS, %) and the global peak systolic circumferential strain normalized to pulse arterial pressure (PAP) (GCS / PAP∙100) were calculated. All patients underwent coronary angiography. The number of coronary arteries (CAs) with >50 % stenosis was determined, and the SYNTAX Score was calculated.Results TA atherosclerosis was not detected in the control group. Among 182 patients, stage 1-5 TA atherosclerosis was found in 23 (12.6 %), 103 (56.6 %), 43 (23.6 %), 7 (3.8 %), and 6 (3.4 %) cases respectively. GCS and GCS / PAD decreased as the ultrasound stage of TA atherosclerosis increased as compared with the control group: 9.2 % and 15.3 for the control group; stage 1, 5.6 % and 8.9 (p<0.001); stage 2, 4.1 % and 5.9 (p<0.001); stage 3, 4 % and 5.8 (p<0.001); stage 4, 3.7 % and 4.9 (p<0.01); and stage 5, 2.6 % and 3.3 (p<0.01), respectively. ROC analysis showed that GCS ≥5.9 % (area under the curve, AUC, 0.94±0.03; p<0.001) and GCS / PAD ≥11.4 (AUC, 0.97±0.02; p <0.001) were predictors of intact TA. Also, GCS ≤4.85 % (AUC, 0.82±0.04; p<0.001) and GCS / PAD ≤8.06 (AUC, 0.87±0.03; p<0.001) were predictors of hemodynamically significant TA atherosclerosis (stages 3-5). GCS ≤4.05 % (AUC, 0.62±0.04; p=0.007) and GCS / PAD ≤5.95 (AUC, 0.61±0.04; p=0.018) were predictors of hemodynamically significant (>50 %) stenosing atherosclerosis of at least one CA. Furthermore, GCS ≤3.75 % (AUC, 0.67±0.07; p=0.039) and GCS / PAD ≤5.15 (AUC, 0.64±0.07; p=0.045) were predictors of severe and advanced coronary atherosclerosis (SYNTAX Score ≥22).Conclusion      GCS and GCS / PAD are new diagnostic markers of structural and functional disorders of TA in atherosclerosis of various grades. GCS and GCS / PAD are independent predictors of high-grade TA atherosclerosis (stages 3-5) with GCS / PAD demonstrating the highest level of significance. GCS and GCS / PAD are non-invasive predictors of severe and advanced CA atherosclerosis.