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 <0.5 mV. Blood plasma samples from femoral vein were collected before catheter ablation. NT ‐pro ANP levels were studied using commercially available assays. There were 216 patients (65±11 years, 59% males, 56% persistent AF , 26% LVA ) included into analyses. NT ‐pro ANP levels in patients with LVA were significantly higher than in those without (median/interquartile range 22 [13–29] versus 15 [9–22] pg/mL, P =0.004). All CMR derived LA diameters correlated significantly with persistent AF ( r ²=0.291–0.468, all P <0.001), LVA ( r ²=0.187–0.306, all P <0.001), and NT ‐pro ANP levels ( r ²=0.258–0.352, P <0.01). On logistic regression multivariable analysis, age (odds ratio=1.090, 95% confidence interval: 1.030–1.153, 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 ...

Natriuretic Peptides in Heart Failure with Preserved Left Ventricular Ejection Fraction: From Molecular Evidences to Clinical Implications

“…ANP has numerous biological effects, including blood pressure lowering effects and renin-angiotensin-aldosterone system (RAAS) inhibition [16,17,18,19,20]. It may affect apical Na channel and Na/K ATPasis basal activity, determining a decreased sodium reabsorption and increased Na excretion, leading to increased natriuresis [20].…”

“…Recent studies focusing on AF patients found that NT-proANP levels correlate with AF type and LA dimensions [18]. Seewoster et al revealed that NT-proANP correlated with LA dimension as determined by cardiac magnetic resonance [18].…”

“…BNP possess vasodilator effects, promoting natriuresis and diuresis. At the myocardial level, BNP inhibits fibrosis and necrosis [16,17,18,19]. Also, it possesses anti-inflammatory effects through monocytes, B lymphocytes and natural killer cell regulation.…”

“…ANP and BNP activate NPR-A while CNP activates NPR-B [10,11,12,13,14,15,16]. NPR-A is found in the lungs, kidneys, adrenal glands, while NPR-B is predominantly found inside fibroblasts [18,19,20].…”

Left atrial function and NT-proANP as markers of AF progression and impaired outcome in patients with heart failure with preserved ejection fraction

“…Recently we demonstrated that CMR-derived LA-EF is associated with AF progression phenotypes and the presence of LVAs. Although there was a significant association between NT-proANP and different LA size parameters, such as LA volume, anterior-posterior, superior-inferior and transversal diameter, the LA volume remained most significantly associated with biomarkers [1]. In another study, however, the association between advanced AF progression and LA-EF was stronger than with LA size only [2] .…”