Journal of Vascular and Endovascular Therapy

Keywords

Acute aortic syndromes;Acute aortic syndromes

Short Communication

Acute aortic syndromes include a spectrum of life-threatening aortic conditions. By convention, acute disease is distinguished from chronic disease at an arbitrary time point of two weeks from initial clinical presentation (hyper acute: <24 hours, acute: 1 to 14 days, subacute: >14 to 90 days, chronic: >90 days) and typically manifests with symptoms [1]. Acute aortic syndromes (AASs) are a group of disease involving the thoracic aorta. Including, acute aortic dissection, intramural aortic hematoma, penetrating aortic ulcer [2]. The incidence of AAS is approximately 50–150 cases per million populations per year, 80% of which are dissections, 15% intramural haematomas (IMH) and 5% penetrating ulcers (PAU) [3]. The classic acute aortic dissection is due to the separation of the layers of the aortic wall. A tear in the intimal layer results in the progression of the dissection (either proximal or retrograde) chiefly due to the entry of blood in between the intima and media. An acute aortic dissection is associated with very high mortality [4]. The most common classifications of AASs are those by Debakey and Stanford. Debakey categorizes AASs in type I (involving ascending aorta, arch and descending thoracic aorta) Type II ( limited to ascending aorta) and type III (involving descending aorta distal to left subclavian artery origin). Stanford categorizes AASs in type A (involving ascending aorta) and type B (not involving ascending aorta) (Figure 1) [2].

Figure 1 Aortic dissection classification: DeBakey and Stanford Classifications.

Prognost is most favorable when patients are treated early. Mortality follows a linear increase with diagnostic delay and can be as high as 2% per hour of delay [5].

Acute aortic syndromes cannot be distinguished from each other clinically, and imaging confirmation is necessary to determine the type of acute aortic syndrome, classify the location extent of the pathology, and identify any anatomic complications [1]. CT is the most used imaging technique in the diagnosis of aortic dissection (77%), given that it is available 24h a day even in remote community hospitals and allows whole aorta visualisation and most of the AAS complications [3]. Conclusive diagnosis of AASs requires urgent computed tomography angiography (CTA) of the chest and abdomen or transesophageal echocardiography (TEE), but pretest selection of patients is needed owing to the risks, costs, and hassles of advanced aortic imaging [6]. So, knowing the importance of earlier treatment is needed to establish the best the pretest probability of AAS was the aortic dissection detection risk score (ADD-RS), endorsed by international guidelines on aortic diseases [6]. This process should include specify questions about risk factors, and pain features, as well as a focused examination to identify findings that are associated with AASs, to define a patient as having a low (≤ 0.5%), moderate (0.5%–5%) or high (> 5%) probability for AAS. The committee suggests no further testing in a population with a low pretest probability (prevalence of AAS of ≤ 0.5%). suggests using a strategy starting with D-dimer for excluding AAS in a population with an intermediate pretest probability (prevalence 0.5%–5%), followed by ECG-gated CT in patients with a positive D-dimer test [7]. If D-dimer testing is not readily available, an alternative acceptable strategy includes performing ECG-gated CT alone and recommends using a strategy starting with ECG-gated CT for assessing patients suspected of having AAS in a population with a high pretest probability (prevalence ≥ 5%) (Figure 2) [5].

Figure 2 Clinical decision aid for assessing pretest probability and conditional recommendations for investigation at a low-risk, moderaterisk and high-risk pretestprobability.

The diagnostic flow chart combines the pre-test probabilities according to clinical data, and the laboratory and imaging tests, as should be done in clinical practice in emergency or chest pain units (Figure 3) [8]. Acute aortic syndrome is a difficult-todiagnose aortic emergency. So its proposed recommendations to aid clinicians in risk stratifying patients and, depending on risk level, suggest further investigations needed [5].

Figure 3 Flowchart for decision-making based on pre-test sensitivity of acute aortic syndrome. AAS = abdominal aortic aneurysm; AD = aorticdissection; CT = computed tomography; MRI = magnetic resonance imaging; TOE = transoesophageal echocardiography; TTE = transthoracicechocardiography.

References

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3. Evangelista A, Maldonado G, Gruosso D, Gutiérrez L, Granato C, et al. (2019) The current role of echocardiography in acute aortic syndrome. Echo Res Pract 6: R53-R63.
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8. Erbel R, Aboyans V, Boileau C, Bossone E, Bartolomeo RD, et al. (2015) Corrigendum to: 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases. Eur Heart J 36: 2779-2779.