From the Guidelines
To exclude aortic dissection in a patient with chest pain, urgent and definitive imaging of the aorta using CT angiography is recommended as the first-line test due to its high sensitivity and specificity (>95%), wide availability, and speed. This approach is based on the most recent and highest quality study available, which found that CT angiography has a high level of accuracy to detect an aortic disorder, with sensitivity of 99% and specificity of 100% 1. When evaluating a patient with suspected aortic dissection, it is crucial to start with a thorough history and physical examination, focusing on risk factors like hypertension, Marfan syndrome, and family history of aortic disease. Assess for classic symptoms such as sudden, severe, tearing chest pain radiating to the back. Physical examination should include evaluation of blood pressure in both arms (a difference >20 mmHg is concerning), pulse deficits, and signs of end-organ ischemia.
Key Steps in Evaluation
- Laboratory tests should include cardiac biomarkers, D-dimer (which has high sensitivity but low specificity), and basic metabolic panel.
- Imaging studies are the most definitive diagnostic tests, with CT angiography of the chest and abdomen with contrast being the first-line test.
- Alternatives include transesophageal echocardiography (especially useful in unstable patients), MRI (for stable patients with contrast allergies or renal insufficiency), or aortography in select cases.
Management While Awaiting Diagnosis
- Control blood pressure (target systolic <120 mmHg) using IV beta-blockers like labetalol or metoprolol, followed by vasodilators if needed, as early diagnosis is crucial and mortality increases approximately 1% per hour in untreated acute dissections 1.
Importance of Early Diagnosis
- Early diagnosis and management of aortic dissection are critical to reduce morbidity, mortality, and improve quality of life, as highlighted by the guidelines for the diagnosis and management of patients with thoracic aortic disease 1.
From the Research
Excluding Aortic Dissection in Patients with Chest Pain
To exclude aortic dissection in a patient with chest pain, several diagnostic approaches can be considered:
- A thorough history and physical examination to identify high-risk patients and those with symptoms suggestive of aortic dissection, such as chest and back pain that progresses downward 2
- The use of imaging tests, including:
- Computed Tomography (CT) scans, which can confirm the diagnosis of aortic dissection and are particularly useful in high-risk patients, even if laboratory tests such as the D-dimer assay are unremarkable 3
- Transesophageal echocardiography, which can establish the diagnosis of aortic dissection and identify alternate cardiovascular pathology responsible for the symptoms in patients without dissection 4
- Aortography, which can be used to confirm the diagnosis of aortic dissection, although it is less commonly used than CT scans and echocardiography 2, 4
- Maintaining a high level of suspicion for aortic dissection, even in patients with initial negative imaging studies, particularly if they have an ascending aortic aneurysm and recent onset chest pain 5
- Considering early operation in patients with suspected type A aortic dissection, even if initial imaging studies are negative, due to the high risk of mortality associated with this condition 5
Laboratory Tests
Laboratory tests, such as the D-dimer assay, may be used to support the diagnosis of aortic dissection, but they should not be relied upon exclusively, as they may not always be abnormal in patients with dissection 3, 6
- The D-dimer assay may be useful in some cases, but it is not a definitive test for aortic dissection and should be interpreted in conjunction with clinical findings and imaging results 3
Clinical Presentation
Aortic dissection can present with a variety of clinical manifestations, including:
- Chest pain, which is the most common symptom 4, 6
- Back pain, which can occur in conjunction with chest pain or as a separate symptom 2, 4
- Syncope, which can occur in some patients with aortic dissection 4, 5
- Abdominal pain, anuria, pulse deficits, and acute congestive heart failure, which can also occur in patients with aortic dissection 6