Imaging and Biomarkers in Acute Aortic Syndromes: Diagnostic and Prognostic Implications

Acute aortic syndrome (AAS) is an emergency and life-threatening condition including aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer and iatrogenic-traumatic aortic injury. An integrated multiparametric approach (clinical history and examination, electrocardiogram, biomarkers and imaging techniques) is recommended in order to make timely and accurate diagnosis, delineate the prognosis, choose the most appropriate therapeutic interventions tailored for the individual patient. Nowadays the best imaging strategy for diagnosing AAS and its complications is a combination of transthoracic echocardiography and computed tomography angiography (CTA). Transesophageal echocardiography tends to be carried out in complicated cases prior to surgical or endovascular therapy, often in the operating room and under general anesthesia. In this regard, intravascular ultrasound and intraluminal phase array imaging may be implemented during the endovascular procedures depending on operator expertise and cost issues. On the other hand, owing to its intrinsic characteristics, magnetic resonance imaging is an ideal imaging technique for serial measurements in patients at risk of AAS or with chronic dissection. Among biomarkers, D-dimer is the closest to "golden status" (high sensitivity and low negative likelihood ratio). Interestingly, 18fluorodeoxyglucose positron emission tomography/CT is increasingly being used along with specific serologic biomarkers (white blood cells, C-reactive protein, fibrinogen and D-dimer) to detect and monitor vascular inflammation affecting the aorta and systemic arteries. It is expected, in the near future, the development of serologic and imaging biomarkers able to early detect clinically-silent pathologic changes in the aorta wall before (primary prevention) and after (secondary prevention) the acute index event.