Contrast-enhanced computed tomography (CT) is an effective tool for assessment of thoracic aortic disease in the modern era. Here, we describe a case of Type A aortic dissection incidentally detected by CT in a 63-year old man. Upon more precise imaging with electrocardiography (ECG)-gated CT, the dissection vanished, revealing it to be an aortic motion artifact. This report highlights the importance of motion artifacts mimicking a dissection flap. CT imaging gated with ECG can distinguish a dissection flap from an artifact.

Acute aortic dissection is a rare but devastating complication during cardiac catheterization. We present the case of an elderly female who incurred a Stanford Type A/DeBakey Type I acute aortic dissection extending into the arch vessels and descending aorta likely occurring during right coronary artery engagement for angioplasty. The patient was treated successfully by immediately sealing the entrance of the dissection via the placement of a stent and anti-impulse therapy. Follow-up computed tomography scan showed complete resolution of the dissection within one month.

Background: Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of thoracic aortic aneurysms (TAAs). Cytokines [Interleukin (IL)-Iβ, IL-2, IL-6, and TNF-α)] increase the expression of MMP-2 and -3. Advanced glycation end products (AGEs) interact with cell receptors to increase the release of cytokines. Circulating soluble receptors for AGEs (sRAGE) and endogenous secretory RAGE (esRAGE) compete with membrane bound RAGE for binding with AGEs and reduce the production of cytokines. It is hypothesized that low levels of serum sRAGE and esRAGE and high levels of AGEs, AGEs/sRAGE, and AGEs/esRAGE would increase the levels of cytokines that would increase the levels MMPs, thus contributing to the formation of TAAs. Methods: The study population was composed of 17 control subjects and 20 patients with TAA. Blood samples were collected for measurement of serum sRAGE, esRAGE, AGEs, cytokines, and MMPs. AGEs, sRAGE, and esRAGE were measured using ELISA kits, whereas the remaining parameters were measured using the Luminex Multi-Analyte system. Results: The levels of sRAGE were lower, while the levels of AGEs, AGEs/sRAGE, AGEs/esRAGE, cytokines and MMPs were higher in patients with TAA compared to controls. The levels of sRAGE were inversely correlated with cytokines and MMPs, while AGEs, AGEs/sRAGE and AGEs/esRAGE were positively correlated with cytokines and MMPs. Cytokines were positively correlated with MMPs. Conclusions: The data suggest that the AGE-RAGE axis may be involved in the pathogenesis of TAA and that low levels of sRAGE and high levels of AGEs, AGEs/sRAGE, and AGEs/esRAGE are risk factors for TAA.

AORTA received almost simultaneously the four separate reports (included in this issue) of iatrogenic aortic dissection following coronary angioplasty [1-3] and transaortic aortic valve replacement [4]. Medical management was successful in all these cases. In an ad hoc review of the literature, we have tabulated the currently available case series of iatrogenic aortic dissection (Table 1). The thrust of these case reports [1-4] and literature review (Table 1) points toward the adequacy of medical management in most cases. For dissections induced by coronary angioplasty, immediate sealing of the inciting proximal coronary tear by stenting appears important in securing safe medical outcome.

The case report by Carrel and colleagues [1] should help surgeons approaching pseudoaneurysms of the coronary button anastomoses after composite graft replacement of the aortic root. We find that such coronary button false aneurysms are uncommon. We have encountered one such false aneurysm among over 500 composite graft root replacements performed (Figure 1). This was in a patient later found to harbor a pathogenic mutation in the TGFBR2 gene (causative of Loeys-Dietz syndrome), which might have contributed to additional tissue weakness. We have repaired several such aneurysms referred from other centers. We believe that careful tightening of the coronary button suture line is of critical importance in avoiding such problems. In our experience, these anastomotic pseudoaneurysms are seen more commonly at the right coronary artery button. These present a special problem, as there is often an accompanying large pseudoaneurysm located anteriorly under the breastbone and in front of the aorta.

Reliable methods for measuring the thoracic aorta are critical for determining treatment strategies in aneurysmal disease. Z-scores are a pragmatic alternative to raw diameter sizes commonly used in adult medicine. They are particularly valuable in the pediatric population, who undergo rapid changes in physical development. The advantage of the Z-score is its inclusion of body surface area (BSA) in determining whether an aorta is within normal size limits. Therefore, Z-scores allow us to determine whether true pathology exists, which can be challenging in growing children. In addition, Z-scores allow for thoughtful interpretation of aortic size in different genders, ethnicities, and geographical regions. Despite the advantages of using Z-scores, there are limitations. These include intra- and inter-observer bias, measurement error, and variations between alternative Z-score nomograms and BSA equations. Furthermore, it is unclear how Z-scores change in the normal population over time, which is essential when interpreting serial values. Guidelines for measuring aortic parameters have been developed by the American Society of Echocardiography Pediatric and Congenital Heart Disease Council, which may reduce measurement bias when calculating Z-scores for the aortic root. In addition, web-based Z-score calculators have been developed to aid in efficient Z-score calculations. Despite these advances, clinicians must be mindful of the limitations of Z-scores, especially when used to demonstrate beneficial treatment effect. This review looks to unravel the mystery of the Z-score, with a focus on the thoracic aorta. Here, we will discuss how Z-scores are calculated and the limitations of their use.