Routine preoperative transthoracic echocardiography for predicting incomplete endothelialization of the watchman left...

Incomplete endothelialization of the left atrial appendage(LAA) occluder potentially affects the long-term efficacy of stroke prevention in atrial fibrillation(AF) patients. This study aims to explore the value of routine preoperative transthoracic echocardiography(TTE) in predicting the endothelialization of Watchman LAA occluder.

This single-center retrospective study included 437 AF patients who underwent the LAA closure with Watchman 2.5 occluder from January 2017 to December 2022. Cardiac CTA was performed 3-6 months after the procedure. Based on contrast infiltration into the LAA cavity, two groups were defined as follows: completely and incompletely endothelialized. The baseline and pre-procedural TTE parameters were analyzed.

The average age was 70.2 years old, with 208 females(47.6 %). The incompletely endothelialized group had an older age (71.4 ± 7.5 vs 69.8 ± 7.6,p = 0.053), a larger left atrial(LA) diameter (44.0 ± 5.9 vs 42.7 ± 6.1 mm,p = 0.045) and a lower left ventricular ejection fraction(LVEF%)(62.5 ± 7.5 vs 63.0 ± 5.4 %,p = 0.016) than the completely endothelialized group. Univariate analysis revealed that incomplete endothelialization was associated with persistent AF(OR:1.68;95 % CI:1.08-2.10;p = 0.021), a higher LA diameter(OR:1.04;95 % CI:1.00-1.07;p = 0.046), a higher left ventricular diastolic diameter(LVDD)(OR:1.05;95 % CI:1.00-1.10;p = 0.032),and the presence of mild mitral stenosis (mean pressure gradient <5 mmHg and mitral valve area > 1.5 cm²,OR:11.29;95 % CI:1.25-102.10;p = 0.031), while it was negatively correlated with mild left ventricular diastolic dysfunction (OR:0.49;95 % CI:0.26-0.94;p = 0.033). Multivariate analysis demonstrated that mild mitral stenosis(OR: 13.79;95 % CI:1.37-139.13;p = 0.026) was an independent predictor for incomplete endothelialization.

Preoperative TTE may predict the outcomes of endothelialization after left atrial appendage occlusion. Mild or severe mitral stenosis is an independent predictive factor for poor endothelial coverage.