Subjective assessment of complexity and prognosis after pulmonary vein isolation as significant predictor for procedural success.

PURPOSE: Subjective estimation of recurrence after atrial fibrillation ablation is an important tool in clinical use. The aim of this study is to evaluate (1) if the subjective complexity of an atrial fibrillation ablation procedure is correlated with rhythm stability and (2) if the subjective prognosis of the operator has a predictive value. METHODS: We prospectively enrolled patients admitted for ablation of atrial fibrillation. Two scores were given immediately after the procedure by the operator: the complexity and the prognosis scores. With routine follow-ups, we tried to evaluate the correlation between the subjective scores and measured outcome. RESULTS: The study population included 611 patients (63 ± 10 years, 37% females, 61% persistent AF). During follow-up (FU) (median 24, IQR 7-36 months), recurrences occurred in 44% patients. Both scores (prognosis and complexity) correlated significantly with age, persistent AF, LA diameter, procedural characteristics, and recurrences. On multivariable analysis, complexity (OR 1.304, 95%CI 1.016-1.675, p = 0.037) and prognosis (OR 1.443, 95%CI 1.080-1.982, p = 0.013) scores remained significant predictors for arrhythmia recurrences. On ROC analysis, both scores showed significant predictive value for rhythm outcomes after catheter ablation (AUC 0.599 and 0.613, both p < 0.001 for complexity and prognosis scores, respectively). CONCLUSIONS: Complexity and prognosis scores are significant predictors for arrhythmia recurrences after AF catheter ablations and even independent when competing with simple risk factors.

Resting heart rate and incident atrial fibrillation: A stratified Mendelian randomization in the AFGen consortium.

BACKGROUND: Both elevated and low resting heart rates are associated with atrial fibrillation (AF), suggesting a U-shaped relationship. However, evidence for a U-shaped causal association between genetically-determined resting heart rate and incident AF is limited. We investigated potential directional changes of the causal association between genetically-determined resting heart rate and incident AF. METHOD AND RESULTS: Seven cohorts of the AFGen consortium contributed data to this meta-analysis. All participants were of European ancestry with known AF status, genotype information, and a heart rate measurement from a baseline electrocardiogram (ECG). Three strata of instrumental variable-free resting heart rate were used to assess possible non-linear associations between genetically-determined resting heart rate and the logarithm of the incident AF hazard rate: <65; 65-75; and >75 beats per minute (bpm). Mendelian randomization analyses using a weighted resting heart rate polygenic risk score were performed for each stratum. We studied 38,981 individuals (mean age 59±10 years, 54% women) with a mean resting heart rate of 67±11 bpm. During a mean follow-up of 13±5 years, 4,779 (12%) individuals developed AF. A U-shaped association between the resting heart rate and the incident AF-hazard ratio was observed. Genetically-determined resting heart rate was inversely associated with incident AF for instrumental variable-free resting heart rates below 65 bpm (hazard ratio for genetically-determined resting heart rate, 0.96; 95% confidence interval, 0.94-0.99; p = 0.01). Genetically-determined resting heart rate was not associated with incident AF in the other two strata. CONCLUSIONS: For resting heart rates below 65 bpm, our results support an inverse causal association between genetically-determined resting heart rate and incident AF.

Rhythm outcomes after catheter ablation of atrial fibrillation. Clinical implication of biomarkers.

Atrial fibrillation (AF) occurs as the result of numerous complex physiological processes in the atria leading to AF promotion and maintenance. Improved diagnostic techniques have identified various biomarkers which may play an important role in the prediction of AF related outcomes (cardio- and cerebrovascular events, as well as mortality and rhythm outcomes). Biomarkers refer to 'biological markers' and biomarkers in blood, urine as well as imaging marker (eg, dimensions (left atrial diameter and volume), anatomical features (left appendage and pulmonary vein anatomy), and physiological pattern (LAA flow velocity)) may play important role(s) as clinically important indices in relation to outcomes after different therapeutic strategies. However, the main domain in the biomarker field has focused on blood-based biomarkers, which are widely used to predict therapeutic success regarding underlying pathophysiological mechanism, such as inflammation, fibrosis, endothelial damage. This review provides an update of the role of clinically relevant biomarkers in AF, with particular focus on AF rhythm outcomes.