Relationship between left ventricular diastolic function and the risk of left atrial appendage thrombus in patients with nonvalvular atrial fibrillation.

Abstract

In patients with nonvalvular atrial fibrillation (NVAF), the impact of left ventricular diastolic function on the risk of left atrial appendage (LAA) thrombus has rarely been studied. This prospective study aimed to investigate the relationship between diastolic function and the risk of LAA thrombus in patients with NVAF. Seventy-six patients with NVAF admitted to receive radiofrequency catheter ablation were prospectively enrolled. All the patients underwent transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) in 24h before ablation. Diastolic function was estimated by TTE including left atrial volume index (LAVI) and E/e', as well as invasive left atrial pressure (LAP) measured during the ablation procedure. LAA peak emptying velocity (LAA-PEV) and the intensity of spontaneous echo contrast (SEC) were determined by TEE. Average E/e', LAVI and mean LAP had a significant positive correlation with the intensity of SEC, the coefficient of correlation were 0.344 (p = 0.002), 0.416 (p < 0.001) and 0.402 (p < 0.001), respectively. After adjustment for CHA2DS2-VASc score and type of AF, multivariate regression analysis revealed that increased LAP (OR 1.144, 95% CI 1.012-1.293, p = 0.031) independently correlated with the risk of LAA thrombus (SEC ≥ Grade 2). LAA-PEV showed a significantly inverse relationship with mean LAP in patients with AF (r = - 0.525, p < 0.001), and in the assessment of elevated LAP with TEE, the LAA-PEV cut-off of 0.40m/s had a sensitivity of 80%, specificity of 81%. Left ventricular diastolic dysfunction may constitute a potential risk for LAA thrombus and stroke. Furthermore, evaluation of LAA emptying with use of TEE is helpful for assessing the LAP status of patients with AF.