Aortic dissection: Prompt diagnosis and emergency treatment are critical
ABSTRACTDiagnosing aortic dissection requires a high index of suspicion, as it may mimic other more common conditions that cause chest pain. Prompt diagnosis is key, as it requires emergency evaluation and treatment for optimal chances of survival. This paper reviews key clinical features as well as laboratory and imaging tests.
KEY POINTS
- Aortic surgery is the treatment of choice for dissection of the ascending aorta, whereas dissection of the descending aorta is initially managed medically.
- Look for an underlying genetic predisposition to aortic disease and, in many instances, screen first-degree relatives for aortic disease.
- Long-term management requires serial imaging of the aorta, blood pressure control, and, for many, future aortic procedures.
- Measuring the D-dimer levels may help in decision-making for appropriate imaging in patients presenting with chest pain, as an elevated level raises the suspicion of dissection. However, more study of this and other biomarkers is needed.
- Advances in molecular genetics and the biology of the aortic wall promise to improve the diagnosis and prognosis of aortic disease.
Genetic evaluation
Genetically triggered causes of aortic dissection should be considered. In many circumstances, referral to a medical geneticist or other practitioner knowledgeable in these conditions is important when these disorders are being evaluated (Table 2).
Many of these disorders have an autosomal dominant inheritance, and the patient should be asked about a family history of aortic disease, aortic dissection, or unexplained sudden death. Features of Marfan syndrome, Loeys-Dietz syndrome, and familial thoracic aortic aneurysm syndromes should be sought. Through comprehensive family studies, it is now recognized that up to 20% of patients with thoracic aortic disease (such as aneurysm or dissection) have another first-degree relative with thoracic aortic disease.2,3,24 Thus, first-degree relatives of patients with aortic aneurysm or dissection should be screened for thoracic aortic aneurysm disease.
Research into molecular genetics is providing a better understanding of the genetics of aortic dissection.3 New mutations associated with aortic dissection are being discovered in signaling pathways as well as elements critical for the integrity of the vascular wall.2,3 However, at present, most patients with aortic dissection will not have a specific identifiable genetic defect.
Not only does genetic testing enable the accurate diagnosis of the affected individual, but also treatments are often based on this diagnosis.3 Importantly, the identification of a specific gene mutation (ie, in TGFBR1 or 2, FBN1, ACTA2, MYH11, and COL3A1) in an affected individual has the potential to identify other family members at risk.3
Follow-up imaging
It is important to continue to image the aorta after aortic dissection. Patients may develop progressive dilation or aneurysm formation of the dissected aorta, pseudoaneurysm formation after repair, or recurrent dissection. Many patients require additional surgery on the aorta because of late aneurysm formation.
CT or MRI is usually performed at least every 6 months in the first 2 years after dissection and at least annually thereafter. More centers are choosing MRI for long-term follow-up to avoid the repeated radiation exposure with serial CT.
Patient education
Besides receiving medical therapy and undergoing imaging, patients with aortic dissection should be educated about this condition.5,21 The patient should be aware of symptoms suggesting dissection and should be instructed to seek attention for any concerning symptoms.
Lifestyle modifications are also important. The patient should be educated about safe activity levels and to avoid heavy isometric exercise, such as weight-lifting. Some patients will have to cease their current occupation because of activity restrictions.
