Reversed Auxiliary Flow to Reduce Embolism Risk During TAVI: A Computational Simulation and Experimental Study

Unusual Aneurysm of a Cervical Aortic Arch: Surgical Repair Improves Fluid Dynamics

The cervical aortic arch is a rare congenital vascular abnormality related to the anomalous development of the aortic arch. We present the case of a 6-year-old patient with a large aneurysmal cervical aortic arch who underwent surgical correction and arch reconstruction. Surgical repair was indicated based on the risk of progressive dilation and rupture, aiming to restore correct geometry and hemodynamics. We evaluated preoperative and postoperative hemodynamics using computational fluid dynamics simulations, and we also identified, within the repaired region, an area that remains affected by greater turbulent flow, requiring follow-up surveillance.

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

Atrial fibrillation (AF) is the most common irregular heartbeat among the world's population and is a major contributor to cardiogenic embolisms and acute ischemic stroke (AIS). However, the role AF flow plays in the trajectory paths of cardiogenic emboli has not been experimentally investigated. A physiological simulation system was designed to analyze the trajectory patterns of bovine embolus analogs (EAs) (n = 720) through four patient-specific models, under three flow conditions: steady flow, normal pulsatile flow, and AF pulsatile flow. It was seen that EA trajectory paths were proportional to the percentage flowrate split of 25–31% along the branching vessels. Overall, AF flow conditions increased trajectories through the left- (LCCA) and right (RCCA)-common carotid artery by 25% with respect to normal pulsatile flow. There was no statistical difference in the distribution of clot trajectories when the clot was released from the right, left, or anterior positions. Significantly, more EAs traveled through the brachiocephalic trunk (BCT) than through the LCCA or the left subclavian. Yet of the EAs that traveled through the common carotid arteries, there was a greater affiliation toward the LCCA compared to the RCCA (p < 0.05).