Embolus Analog Trajectory Paths Under Physiological Flowrates Through Patient-Specific Aortic Arch Models.

Area of Science:

• Cardiovascular Science
• Biomedical Engineering
• Hemodynamics

Background:

• Atrial fibrillation (AF) is the most common cardiac arrhythmia.
• AF is a major risk factor for cardiogenic embolisms and acute ischemic stroke (AIS).
• The influence of AF-induced flow dynamics on embolus trajectory remains under-investigated.

Purpose of the Study:

• To experimentally investigate the trajectory paths of cardiogenic emboli under AF flow conditions.
• To analyze embolus analog (EA) distribution in patient-specific vascular models.
• To compare EA trajectories under steady, normal pulsatile, and AF pulsatile flow.

Main Methods:

• Utilized a physiological simulation system with 720 bovine embolus analogs (EAs).
• Employed four patient-specific vascular models.
• Simulated three flow conditions: steady, normal pulsatile, and AF pulsatile flow.

Main Results:

• EA trajectory paths correlated with flow rate splits (25-31%) in branching vessels.
• AF flow increased EA trajectories to the left (LCCA) and right (RCCA) common carotid arteries by 25% compared to normal pulsatile flow.
• More EAs traveled through the brachiocephalic trunk (BCT) than LCCA or left subclavian; however, among those reaching common carotids, LCCA showed greater EA affiliation.

Conclusions:

• AF flow dynamics significantly impact embolus distribution, favoring pathways to the common carotid arteries.
• Understanding these altered trajectories is crucial for stroke risk assessment in AF patients.
• The study provides novel experimental insights into AF-related embolic stroke mechanisms.