Thrombus within an aortic aneurysm does not reduce pressure on the aneurysmal wall

Area of Science:

• Vascular Surgery
• Aneurysm Research
• Biomedical Engineering

Background:

• The role of thrombus in abdominal aortic aneurysm (AAA) rupture risk is debated.
• Existing literature presents conflicting evidence on whether thrombus increases or decreases rupture risk.
• Understanding thrombus impact is crucial for endovascular AAA repair strategies, particularly concerning endoleaks.

Purpose of the Study:

• To investigate the relationship between thrombus within an AAA and the pressure exerted on the aneurysmal wall.
• To determine if thrombus presence influences the risk of AAA rupture.

Main Methods:

• Pressure measurements were taken within the aneurysmal thrombus of nine patients undergoing open AAA repair.
• Intra-aneurysmal thrombus pressure was compared to systemic arterial pressure.
• Correlation analysis assessed the relationship between thrombus thickness and pressure transmission to the aneurysmal wall.

Main Results:

• Mean and pulse pressures within the aneurysmal thrombus closely correlated with systemic pressures.
• No significant relationship was found between thrombus thickness and the transmission of mean or pulse pressure to the aneurysmal wall.
• Pressure at the aneurysmal wall was not reduced by the presence of thrombus.

Conclusions:

• Intra-aneurysmal thrombus does not attenuate mean or pulse pressure at the aneurysmal wall.
• The findings suggest that thrombus within an AAA does not reduce the risk of aneurysm rupture.
• This has implications for risk stratification and treatment planning in AAA management.