Remote dielectric sensing predicts elevated left atrial pressure in patients with atrial fibrillation

Background: There are currently no established non-invasive indices of echocardiography for elevated left atrial pressure (LAP) especially in patients with atrial fibrillation (AF). Remote dielectric sensing (ReDS) is a novel noninvasive electromagnetic energy-based technology that quantifies total lung fluid, enabling the monitoring of volume status in patients with heart failure. The utility of ReDS for estimating LAP in patients with AF remains unknown. Methods: We prospectively investigated patients with AF in whom LAP was directly measured during catheter ablation for AF, and ReDS measurements were conducted the day before ablation. Elevated LAP was defined as LAP >= 15 mmHg. Results: A total of 61 patients were included (median age 66 years, 38 % female). Among them, 26 patients had elevated LAP. There was a positive correlation between ReDS and LAP (r = 0.363, P = 0.004). Receiver operating characteristic curve analysis for the prediction of elevated LAP demonstrated that the best cut-off value of ReDS was 30 %, with a sensitivity of 65 %, specificity of 69 %, and an area under the curve of 0.703 (95 % confidence interval 0.568-0.837). Multivariate logistic regression analysis revealed that ReDS was an independent predictor of elevated LAP, among covariates including left ventricular ejection fraction, the ratio of early transmitral flow velocity to septal mitral annular early diastolic velocity, and left atrial volume index. Conclusions: Our results suggest ReDS could be a valuable marker of elevated LAP even in patients with AF. Further studies are needed to elucidate the effectiveness of a ReDS-guided decongestive strategy in patients with heart failure.