Left atrial appendage inversion: First computational study to shed light on the phenomenon

Area of Science:

• Cardiovascular Surgery
• Medical Device Technology
• Biomedical Engineering

Background:

• Left atrial appendage inversion is a rare but serious complication during cardiac procedures like cardiopulmonary bypass.
• Inversion can lead to mitral valve obstruction and severe patient outcomes.
• The underlying mechanisms and factors influencing appendage inversion remain poorly understood.

Purpose of the Study:

• To investigate the conditions and factors contributing to left atrial appendage inversion.
• To understand the relationship between appendage morphology and inversion susceptibility.
• To explore potential strategies for mitigating or correcting appendage inversion.

Main Methods:

• Utilized four patient-specific left atrial appendage morphologies (chicken wing, cactus, cauliflower, windsock) derived from CT scans.
• Developed numerical models of these morphologies.
• Applied simulated pressure loading patterns to assess inversion and recovery dynamics.

Main Results:

• Appendage morphologies exhibited varying susceptibility to inversion based on their specific shapes.
• Appendage recovery occurred at pressures significantly lower than ventricular pressures.
• Restoring physiological left atrium pressure alone was insufficient for appendage recovery.

Conclusions:

• Appendage morphology is a critical factor determining inversion tendency.
• Low-pressure interventions, potentially via trans-catheter methods, may correct inversion.
• These findings suggest less invasive approaches could be viable alternatives to surgery for managing appendage inversion.