Three-dimensional transesophageal echocardiography for descending aortic atheroma: a preliminary study

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.

Aortic calcifications on routine preoperative chest X-ray and perioperative stroke during cardiac surgery: a nested matched case-control study

OBJECTIVES

Perioperative stroke in cardiac surgery is most often embolic in origin. Preoperative chest X-ray (CXR) is routinely used amongst others to screen for relevant aortic calcification, a potential source of embolic stroke. We performed a nested matched case-control study to examine the relationship between aortic calcifications on CXR and the occurrence of embolic stroke.

METHODS

Among all consecutive patients undergoing cardiac surgery in our hospital between January 2014 and July 2017, we selected all patients with perioperative embolic stroke (cases). Controls, all patients without perioperative stroke, were matched on age, sex and type of surgery. All preoperative CXRs were scored for aortic calcifications (none, mild, severe) in the ascending aorta, arch, aortic knob and descending aorta.

RESULTS

Out of the 3038 eligible patients, 27 cases were detected and 78 controls were selected. In the stroke group, mild-to-severe calcifications were found least often in the ascending aorta [9% of patients, 95% confidence interval (CI) 1-29%] and most frequently in the aortic knob (63% of patients, 95% CI 44-78%). The distribution of aortic calcification was comparable in cases versus controls.

CONCLUSIONS

Calcification burden was comparable between the cases and their matched controls. In our study population, CXR findings on aortic calcification were not related to the risk of embolic stroke. In these patients, the correlation between findings on the preoperative CXR and the risk of stroke might, therefore, be too weak to use the CXR directly for the assessment of the safety of manipulating the ascending aorta during surgery.

Role of Echocardiography in Assessment of Cardioembolic Sources: a Strong Diagnostic Resource in Patients with Ischemic Stroke

PURPOSE OF REVIEW

This review will discuss the most frequent sources of cardiac embolism and the role of echocardiography in these different clinical settings, and, in addition, provide suggestions about the choice between transthoracic (TTE) and transesophageal echocardiography (TEE).

RECENT FINDINGS

Stroke is the third leading cause of death in industrial countries, and 15-40% of all ischemic strokes are due to cardioembolism. TTE and TEE are cornerstones in the detection of cardioembolic sources and provide fundamental information about the embolic risk and most suitable treatment of these patients, improving long-term outcomes. Echocardiography is a widely available, inexpensive, and safe diagnostic tool that is almost free from contraindication, and these elements allow the common use of this technique in almost all the patients with ischemic stroke. The most common cardioembolic sources include left atrial appendage thrombosis during atrial fibrillation; vegetations in infective endocarditis; cardiac masses including left ventricular thrombosis, cardiac tumors, etc.; atherosclerotic plaques; and passageways within the heart serving as conduits for paradoxical embolization, e.g., patent foramen ovale.

Reconstruction of the descending thoracic aorta by multiview compounding of 3-D transesophageal echocardiographic aortic data sets for improved examination and quantification of atheroma burden

A robust and efficient approach to reconstruction of the descending thoracic aorta from contiguous 3-D transesophageal echocardiographic (TEE) images is proposed. An ad hoc image acquisition protocol was designed to acquire ordered and partially overlapped 3-D TEE data sets, followed by dedicated image processing to align and fuse all acquired data sets. Alignment strategy implemented pairwise rigid registration guided by a priori knowledge, and it was validated using artificially misaligned images. Image fusion was finally performed to enable visualization and analysis of extended field-of-view of the acquired aorta. The application of different fusion techniques was also investigated. The method was applied to a population of 17 consecutive patients. Qualitative and quantitative results supported the feasibility and accuracy of the proposed approach. In a clinical scenario, its application could allow the quantitative assessment of aortic plaque burden in the descending thoracic aorta from 3-D TEE images.