Blood flow analysis with computational fluid dynamics in the left atrium after left atrial plication: a prospective study.

This study aimed to evaluate blood flow stagnation in an enlarged left atrium (LA) and prove that left atrial plication (LAP) could alleviate the stagnation. Five patients with chronic atrial fibrillation who underwent mitral valve surgery followed by LAP for an enlarged LA with a ≥ 60-mm diameter were included. We performed computational fluid dynamics (CFD) analysis using preoperative and postoperative computed tomography and four-dimensional flow magnetic resonance imaging. Additionally, computer graphics were used to create virtual left atrial appendage resection (LAAR) images. We performed CFD analysis to assess blood flow stagnation in the LA for three groups: preoperative, LAAR, and LAP. When the average and constant stagnation volumes were both set to 100 preoperatively, the average stagnation volumes of the LAAR and LAP groups were 67.42 ± 18.64 and 35.88 ± 8.20, respectively. The constant stagnation volumes of these groups reduced to 45.01 ± 7.43 and 21.14 ± 7.70, respectively. The LAP group also had significantly lower average and constant stagnation volumes than those in the LAAR group (p = 0.006 and p = 0.033, respectively). Blood flow stagnation was noted in the LAA and enlarged LA. CFD analysis revealed that LAP for the enlarged LA improved blood flow stagnation more than the virtual LAAR alone. UMIN000049923.