Association Between Cardiovascular Magnetic Resonance‐Derived Left Atrial Dimensions, Electroanatomical Substrate and NT‐proANP Levels in Atrial Fibrillation

Abstract

Background: Enlargement of left atrial ( LA ) size indicates advanced disease stage in patients with atrial fibrillation ( AF ) and is associated with poor success of different AF therapies. Two dimensional echocardiographic LA measurements do not reliably reflect the true size of LA anatomy. The aim of the current study was: 1) to analyze cardiovascular magnetic resonance ( CMR )‐derived LA dimensions and their association with low voltage areas ( LVA ); and 2) to investigate the association between these parameters and NT ‐pro ANP (N‐terminal proatrial natriuretic peptide) levels. Methods and Results: Patients undergoing first AF catheter ablation were included. All patients underwent CMR imaging (Ingenia 1.5T Philips) before intervention. CMR data ( LA volume, superior–inferior, transversal and anterior–posterior LA diameters) were measured in all patients. LVA were determined using high‐density maps and a low voltage threshold P =0.004). All CMR derived LA diameters correlated significantly with persistent AF ( r ²=0.291–0.468, all P r ²=0.187–0.306, all P r ²=0.258–0.352, P P =0.003), females (odds ratio=2.686, 95% confidence interval: 1.047–6.891, P =0.040), and LA volume (odds ratio=1.022, 95% confidence interval: 1.009–1.035, P =0.001) remained significant predictors for LVA . Conclusions: Left atrial CMR parameters are associated with persistent AF , low voltage areas and NT ‐pro ANP levels. LA volume is the most significant predictor for LVA .