Prognostic value of high-sensitive troponin T for predicting cardiovascular events after atrial fibrillation ablation

Recurrence After Atrial Fibrillation Ablation and Investigational Biomarkers of Cardiac Remodeling

BACKGROUND

Recurrence after atrial fibrillation (AF) ablation remains common. We evaluated the association between recurrence and levels of biomarkers of cardiac remodeling, and their ability to improve recurrence prediction when added to a clinical prediction model.

METHODS AND RESULTS

Blood samples collected before de novo catheter ablation were analyzed. Levels of bone morphogenetic protein-10, angiopoietin-2, fibroblast growth factor-23, insulin-like growth factor-binding protein-7, myosin-binding protein C3, growth differentiation factor-15, interleukin-6, N-terminal pro-brain natriuretic peptide, and high-sensitivity troponin T were measured. Recurrence was defined as ≥30 seconds of an atrial arrhythmia 3 to 12 months postablation. Multivariable logistic regression was performed using biomarker levels along with clinical covariates: APPLE score (Age >65 years, Persistent AF, imPaired eGFR [<60 ml/min/1.73m2], LA diameter ≥43 mm, EF <50%; which includes age, left atrial diameter, left ventricular ejection fraction, persistent atrial fibrillation, and estimated glomerular filtration rate), preablation rhythm, sex, height, body mass index, presence of an implanted continuous monitor, year of ablation, and additional linear ablation. A total of 1873 participants were included. A multivariable logistic regression showed an association between recurrence and levels of angiopoietin-2 (odds ratio, 1.08 [95% CI, 1.02-1.15], P=0.007) and interleukin-6 (odds ratio, 1.02 [95% CI, 1.003-1.03]; P=0.02). The area under the receiver operating characteristic curve of a model that only contained clinical predictors was 0.711. The addition of any of the 9 studied biomarkers to the predictive model did not result in a statistically significant improvement in the area under the receiver operating characteristic curve.

CONCLUSIONS

Higher angiopoietin-2 and interleukin-6 levels were associated with recurrence after atrial fibrillation ablation in multivariable modeling. However, the addition of biomarkers to a clinical prediction model did not significantly improve recurrence prediction.

ABC-AF-Stroke score predicts thromboembolism in non-anticoagulated patients following successful atrial fibrillation ablation: a report from the Chinese Atrial Fibrillation Registry

BACKGROUND

The age, biomarkers, and clinical history (ABC)-atrial fibrillation (AF)-Stroke score have been proposed to refine stroke risk stratification, beyond what clinical risk scores such as the CHA2DS2-VASc score can offer. This study aimed to identify risk factors associated with thromboembolism and evaluate the performance of the ABC-AF-Stroke score in predicting thromboembolism in non-anticoagulated AF patients following successful ablations.

METHODS

A total of 2692 patients who underwent successful ablations with discontinued anticoagulation after a 3-month blanking period in the Chinese Atrial Fibrillation Registry (CAFR) between 2013 and 2019 were included. Cox regression analysis was conducted to present the association of risk factors with thromboembolism risk. The ABC-AF-Stroke score was evaluated in terms of discrimination, including concordance index (C-index), net reclassification improvement (NRI) and integrated discrimination improvement (IDI), clinical utilization by decision curve analysis (DCA), and calibration by comparing the predicted risk with the observed annualized event rate.

RESULTS

After a median follow-up of 3.5 years, 64 patients experienced thromboembolism events. Age, prior history of stroke/transient ischemic attack (TIA), high-sensitivity cardiac troponin T (cTnT-hs), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were independently associated with thromboembolism risk. The ABC-AF-Stroke score performed statistically significantly better than the CHA2DS2-VASc score in terms of C-index (0.67, 95% confidence interval [CI]: 0.59-0.74 vs. 0.60, 95% CI: 0.52-0.67, P = 0.030) and reclassification capacity. The DCA implied that the ABC-AF-Stroke score could identify more thromboembolism events without increasing the false positive rate compared to the CHA2DS2-VASc score. The calibration curve showed that the ABC-AF-Stroke score was well calibrated in this population.

CONCLUSIONS

In this real-world study enrolling non-anticoagulated AF patients following successful ablations, age, prior history of stroke/TIA, level of NT-proBNP, and cTnT-hs were independently associated with an increased risk of thromboembolism. The ABC-AF-Stroke score was well-calibrated and statistically significantly outperformed the CHA2DS2-VASc score in predicting thromboembolism risk.

Preprocedural Troponin T Levels Predict the Improvement in the Left Ventricular Ejection Fraction After Catheter Ablation of Atrial Fibrillation/Flutter

Background

Left ventricular (LV) systolic dysfunction is reversible in some patients once the arrhythmia is controlled. However, identifying this arrhythmia‐induced cardiomyopathy among patients with LV systolic dysfunction is challenging. We explored the factors predicting the reversibility of the LV ejection fraction (LVEF) after catheter ablation of atrial fibrillation and/or atrial flutter in patients with LV systolic dysfunction.

Methods and Results

Forty patients with a reduced LVEF (LVEF <50%; 66.2±10.7 years; 32 men) who underwent atrial fibrillation/atrial flutter ablation were included. Transthoracic echocardiography was performed before and during the early (<4 days) and late phases (>3 months) after the ablation. Responders were defined as having a normalized LVEF (≥50%) during the late phase after the ablation. The LVEF improved from 39.8±8.8 to 50.9±10.9% at 1.2±0.6 days after the procedure, and to 56.2±12.2% at 9.6±8.0 months after the procedure (both for P<0.001). Thirty (75.0%) patients were responders. The preprocedural echocardiographic parameters were comparable between the responders and nonresponders. In the multivariate analysis, the preprocedural high‐sensitivity troponin T was the only independent predictor of the recovery of the LV dysfunction during the late phase after ablation (odds ratio, 1.17; 95% CI, 1.06–1.33; P=0.001), and a level of ≤12 pg/mL predicted recovery of the LV dysfunction with a high accuracy (sensitivity, 90.0%; specificity, 76.7%; positive predictive value, 56.3%; and negative predictive value, 95.8%).

Conclusions

Preprocedural high‐sensitivity troponin T levels might be a simple and useful parameter for predicting the reversibility of the LV systolic dysfunction after atrial fibrillation/atrial flutter ablation in patients with a reduced LVEF.