Reflected wave intensity increases based on aortic diameter after endovascular aortic therapy in a goat model

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Vascular Surgery

Background:

• Endovascular aortic repair (EVAR) is a common treatment for aortic aneurysms.
• Increased reflected waves after EVAR have been linked to adverse left ventricular (LV) diastolic function and poor prognosis.
• The relationship between enhanced reflected waves and aortic dimensions post-EVAR requires further elucidation.

Purpose of the Study:

• To investigate the association between augmented reflected wave amplitude and aortic diameter following EVAR.
• To evaluate the impact of EVAR on wave intensity (WI), aortic diameter, and arterial stiffness.
• To explore the correlation between negative waves (NW) and hemodynamic parameters post-EVAR.

Main Methods:

• EVAR was performed in seven healthy goats.
• Measurements included wave intensity (WI), aortic diameter, and the stiffness parameter β.
• Analysis focused on the relationship between negative waves (NW) and aortic diameter changes after EVAR.

Main Results:

• A significant increase in stiffness parameter β (3.5 ± 0.3 to 15.9 ± 4.7, p=0.018) and a decrease in aortic diameter change (6.9 ± 0.7% to 2.7 ± 0.4%, p=0.018) were observed post-EVAR.
• Negative waves (NW) were significantly amplified after EVAR (-589.8 ± 143.4 to -1192.3 ± 303.7 mmHg·m/sec³, p=0.043).
• NW showed a significant positive correlation with maximum (R=0.707, p=0.038) and minimum (R=0.724, p=0.033) aortic diameters.

Conclusions:

• Reflected waves are enhanced after EVAR and correlate with aortic diameter at the stent-graft landing zone.
• The amplification of NW post-EVAR suggests a potential mechanism for LV diastolic dysfunction.
• Clinicians should consider the implications of smaller aortic landing zone diameters in patients undergoing EVAR regarding potential LV dysfunction.