Left atrial volume affects the correlation of voltage map with magnetic resonance imaging.

BACKGROUND: The low-voltage area detected by electroanatomic mapping (EAM) is a surrogate marker of left atrial fibrosis. However, the correlation between the EAM and late gadolinium enhancement magnetic resonance imaging (LGE-MRI) has been inconsistent among studies. This study aimed to investigate how LA size affects the correlation between EAM and LGE-MRI. METHODS: High-density EAMs of the LA during sinus rhythm were collected in 22 patients undergoing AF ablation. The EAMs were co-registered with pre-ablation LGE-MRI models. Voltages in the areas with and without LGE were recorded. Left atrial volume index (LAVI) was calculated from MRI, and LAVI > 62 ml/m2 was defined as significant LA enlargement (LAE). RESULTS: Atrial bipolar voltage negatively correlates with the left atrial volume index. The median voltages in areas without LGE were 1.1 mV vs 2.0 mV in patients with vs without significant LAE (p = 0.002). In areas of LGE, median voltages were 0.4 mV vs 0.8 mV in patients with vs without significant LAE (p = 0.02). A voltage threshold of 1.7 mV predicted atrial LGE in patients with normal or mildly enlarged LA (sensitivity and specificity of 74% and 59%, respectively). In contrast, areas of voltage less than 0.75 mV correlated with LGE in patients with significant LA enlargement (sensitivity 68% and specificity 66%). CONCLUSIONS: LAVI affects left atrial bipolar voltage, and the correlation between low-voltage areas and LGE-MRI. Distinct voltage thresholds according to the LAVI value might be considered to identify atrial scar by EAM.

Baseline natriuretic peptides as a predictor of atrial fibrillation recurrence after radiofrequency-based pulmonary vein isolation in a non-heart failure population: A subanalysis from DECAAF II.

BACKGROUND: Brain natriuretic peptide (BNP) is a marker of myocardial stretch and may have prognostic significance in patients with atrial fibrillation (AF) without heart failure (HF). We investigated the association between baseline BNP levels and arrhythmia recurrence following pulmonary vein isolation (PVI) among patients with persistent AF without HF. METHODS: We analyzed 125 patients with persistent AF without HF who had baseline BNP measured from the DECAAF II trial. The primary outcome was arrhythmia recurrence following ablation. The baseline characteristics across the two groups were compared using Chi-square test and Wilcoxon rank test accordingly. Cox regression analysis was used to analyze the association between baseline BNP levels and the primary outcome. RESULTS: Across the entire cohort, 64 (51%) patients experienced arrhythmia recurrence. When comparing patients who experienced arrythmia recurrence to patients who did not, patients with recurrent arrhythmia had higher levels of pre-ablation BNP, as evidenced by differences in means (330.05 pg/mL) compared to patients without recurrent arrhythmia (182.39 pg/mL) (p < .05). A cut-off BNP value of 300 pg/mL provided the largest area under curve (AUC) of receiver-operating characteristic (ROC) curve on univariate logistic regression. On unadjusted Cox analysis, for every 100 unit increase in BNP, the hazard ratio for the primary outcome increased 1.09 (1.026-1.158) times (p = .004). After adjusting for sex, hypertension, and stroke, the results remained significant (HR = 1.8516, CI 95% [1.0139 - 3.381], p = .045). CONCLUSION: In the non-heart failure population, BNP levels predict AF recurrence following PVI in persistent AF patients.

The relationship between atrial fibrillation and coronary artery disease: Understanding common denominators.

Atrial fibrillation (AF) and coronary artery disease (CAD) are highly prevalent cardiovascular conditions. The coexistence of both diseases is common as they share similar risk factors and common pathophysiological characteristics. Systemic inflammatory conditions are associated with an increased incidence of both AF and CAD. The presence of both entities increases the incidence of complications and adverse outcomes. Furthermore, their coexistence poses challenges for the management of patients, particularly with respect to anticoagulation and rhythm management. In this review, we aim to better understand the relationship between AF and CAD by detailing basic molecular pathophysiology, assessing therapeutic guidelines, and describing interactions between the two conditions.