What is acute aortic syndrome?

From the Guidelines

Acute aortic syndrome is a life-threatening condition characterized by disruptions in the aortic wall, including aortic dissection, intramural hematoma, and penetrating aortic ulcer, which requires immediate medical attention to reduce morbidity, mortality, and improve quality of life. According to the most recent guidelines, acute aortic syndrome encompasses these three main entities, which present similarly with sudden, severe chest or back pain often described as tearing or ripping in nature 1.

Key Characteristics

• Aortic dissection: a tear in the inner layer of the aorta allowing blood to flow between the layers
• Intramural hematoma: bleeding into the aortic wall without an intimal tear
• Penetrating atherosclerotic ulcer: an ulceration that penetrates through the intima into the media These conditions are associated with significant morbidity and mortality, with in-hospital mortality rates reaching up to 60% 1.

Diagnosis and Management

Diagnosis typically requires advanced imaging such as CT angiography, MRI, or transesophageal echocardiography. Initial management focuses on pain control and blood pressure reduction, typically using intravenous beta-blockers like labetalol as the first choice due to its alpha- and beta-blocking properties, with a target systolic blood pressure of below 120 mmHg and heart rhythm ≤60 beats per minute 1. If these are insufficient, vasodilators like nicardipine or nitroprusside may be added.

Importance of Centralized Care

Care should be centralized in experienced centers and managed by aorta teams to improve outcomes, with early placement of an arterial line to monitor blood pressure invasively and admission to an intensive care unit being advisable 1. The pathophysiology involves weakening of the aortic wall, often due to hypertension, genetic disorders like Marfan syndrome, or atherosclerosis, leading to structural compromise of this major blood vessel 1.

From the Research

Definition of Acute Aortic Syndrome

Acute aortic syndrome (AAS) refers to a group of severe, life-threatening disorders of the aorta, including:

• Acute aortic dissection
• Intramural haematoma (IMH)
• Penetrating aortic ulcer (PAU) 2, 3, 4, 5
• Unstable thoracic aortic aneurysms 6

Characteristics of Acute Aortic Syndrome

AAS is characterized by:

• Acute presentation of patients with characteristic "aortic pain" caused by one of several life-threatening thoracic aortic conditions 3, 4, 5
• Imminent risk of aortic rupture 4
• High morbidity and mortality if left untreated or misdiagnosed 2, 4

Diagnosis of Acute Aortic Syndrome

The diagnosis of AAS can be made using imaging modalities such as:

• CT scans, particularly multi-detector CT (MDCT) 6
• Echocardiography 2
• MRI 2, 6
• Trans-esophageal echocardiography may be required as a problem-solving tool in select cases 6

Management of Acute Aortic Syndrome

The management of AAS remains a therapeutic challenge and requires a multidisciplinary team approach 2, 3, 4, 5. Treatment options include:

• Endovascular strategies, such as endovascular aortic stent grafts 4, 5
• Open surgical treatment 2, 4
• Medical management, including control of blood pressure to reduce aortic wall stress 2