Creation and Validation of an Algorithm for Predicting the Recurrence of Atrial Fibrillation Following Pulmonary Vein Isolation by Utilizing Real-World Data and Ensemble Modeling Techniques.

Introduction Catheter ablation (CA) of atrial fibrillation (AF) represents a mainstay in the treatment of this increasingly prevalent arrhythmia. Prospective clinical trials investigating the efficacy of CA may poorly represent real-world patient populations. However, many real-world clinical datasets possess missing data, which may impede their applicability in research. Thus, we sought to use ensemble modeling to address missing data and develop a model to estimate the probability of AF recurrence following CA. Methods We retrospectively analyzed clinical variables in 476 patients who underwent an initial CA of AF. Univariate and multivariate logistic regression was performed to determine those variables predictive of AF recurrence. A multivariate logistic model was created to estimate the probability of AF recurrence after CA. Missing data were addressed using ensemble modeling, and variable selection was performed using the aggregate of multiple models. Results After analysis, six variables remained in the model: AF during the post-procedural blanking period, coexistence of atrial flutter, end-stage renal disease, reduced left ventricular ejection fraction, prior failure of anti-arrhythmic drugs, and valvular heart disease. Predictive modeling was performed using these variables for 1000 randomly partitioned datasets (80% training, 20% testing) and 1000 random imputations for each partitioned dataset. The model predicted AF recurrence with an accuracy of 74.34 ± 3.99% (recall: 54.03 ± 8.15%; precision: 89.30 ± 4.21%; F1 score: 81.08 ± 3.65%).  Conclusion We successfully identified six clinical variables that, when modeled, predicted AF recurrence following CA with a high degree of classification accuracy. Application of this model to patients undergoing CA of AF may help identify those at risk of post-procedural AF recurrence.

Spontaneous Closure of a Coronary Artery Bypass Graft Pseudoaneurysm Embedded in a Mediastinal Hematoma.

Coronary artery bypass graft (CABG) pseudoaneurysms are a rare but often unrecognized clinical entity. They are prone to rupture and hemodynamic compromise and should therefore be on the differential in the appropriate patient. We present a case of a gentleman with a recent CABG surgery who presented with acute onset dyspnea and a large pleural effusion. Imaging revealed a saphenous vein graft pseudoaneurysm embedded in a mediastinal hematoma. Four weeks later, prior to planned stenting, the pseudoaneurysm had spontaneously closed. This case highlights an unusual acute presentation of a CABG pseudoaneurysm and a multidisciplinary approach to its management.