What is the evaluation for aortic dissection (Aortic Dissection)?

From the Guidelines

Evaluation of aortic dissection requires immediate imaging with CT angiography of the chest and abdomen with contrast as the first-line diagnostic test. This approach is supported by the most recent and highest quality study, which emphasizes the importance of timely diagnosis and management in reducing morbidity and mortality 1. The study highlights that acute aortic syndrome, including aortic dissection, typically presents with sudden onset of severe, tearing, anterior, or interscapular back pain, and that risk factors include hypertension, family history, and underlying collagen vascular disorders.

Key considerations in the evaluation of aortic dissection include:

• Confirming the presence of aortic dissection
• Classifying the location of the dissection using the Stanford type A or B (and/or DeBakey types I, II, or III)
• Identifying entry and reentry sites
• Evaluating the patency of the false lumen
• Detecting the presence or absence of aortic branch involvement
• Assessing involvement of the coronary ostia
• Evaluating aortic valve competency
• Determining the presence or absence of extravasated blood in the mediastinal, pleural, or pericardial spaces and sizing of the aorta

Initial management includes:

• Pain control with IV opioids
• Blood pressure reduction with IV beta-blockers (esmolol 50-200 μg/kg/min or metoprolol 5mg IV every 5 minutes up to 3 doses) to target systolic BP of 100-120 mmHg, and heart rate below 60 bpm
• If additional BP control is needed, add vasodilators like nicardipine (5-15 mg/hr) or nitroprusside (0.3-10 μg/kg/min)
• Type A dissections (involving ascending aorta) require emergency surgical repair, while uncomplicated Type B dissections (descending aorta only) can often be managed medically, as supported by guidelines from 2010 1 and 2001 1.

Laboratory tests should include complete blood count, basic metabolic panel, cardiac enzymes, and coagulation studies to assess for complications and prepare for potential intervention. Rapid diagnosis and appropriate management are critical as mortality increases approximately 1-2% per hour in untreated acute dissections.

From the Research

Aortic Dissection Evaluation

• Aortic dissection is a life-threatening cardiovascular emergency that requires immediate diagnosis and treatment, mainly associated with hypertension and the Marfan syndrome 2.
• The clinical presentation of aortic dissection can be variable and may mimic other medical and surgical conditions, with the most prevalent symptom being excruciating chest pain 3.
• Essential treatment includes rapid initiation of pharmacologic agents to control hypertension, and aortic dissection involving the ascending aorta necessitates immediate surgical repair 3.

Diagnosis and Imaging

• Transesophageal echocardiography (TEE) has revolutionized the diagnosis of aortic dissection, allowing for rapid and safe assessment of the condition 2.
• Echocardiographic hallmarks of aortic dissection include the presence of a dissection membrane, rupture sites in the membrane, aortic regurgitation, and pericardial effusion 2.
• In suspected cases of acute aortic dissection, immediate imaging with chest computed tomography scan followed by transthoracic echocardiography (TTE) is essential to confirm diagnosis 4.

Management and Treatment

• Immediate medical management of acute aortic dissection aims to control the heart rate, systolic blood pressure, and pain 4.
• Patients with Type A acute aortic dissection should be referred to cardiothoracic surgeons for emergency aortic surgery, while those with Type B acute aortic dissection may require surgical or endovascular interventions if indicated 4.
• The treatment of choice for acute aortic dissection currently includes sodium nitroprusside and intravenous propranolol hydrochloride, with esmolol hydrochloride being a suitable alternative in certain cases 5.
• Beta-blockers are commonly used as first-line therapy for chronic type B aortic dissections to decrease aortic wall stress, although there is limited evidence to support their use compared to other antihypertensive medications 6.