Frisch, Daniel R.

Background: Cardiac amyloidosis (CA) in conjunction with atrial fibrillation (AF) presents unique management challenges. CHA2DS2VASc score in these patients is believed to underestimate the risk of ischemic stroke, necessitating a better predictive model in these patients. Methods: Data was obtained from the National Readmission Database (NRD). Outcomes between CA-AF and no-CA-AF were compared using multivariate regression analysis to calculate adjusted odds ratios (aOR). AutoScore; an interpretable machine learning framework, was used to develop a stroke risk prediction model, the predictive accuracy of which was evaluated with an area under the curve (AUC) using the receiver operating characteristic analysis. Results: A total of 11,860,804 (CA-AF 22,687 [0.19%] and no-CA-AF 11,838,117) patients were identified from 2015-2019. The adjusted odds of mortality (aOR 1.41 and 1.29), stroke (aOR 1.78 and 1.74), non-intracranial hemorrhage (aOR 2.10 and aOR 1.85), and intracranial hemorrhage (aOR 14.4 and aOR 4.26) were significantly higher in CA-AF compared with non-CA-AF at both index admission and 30-days, respectively. The CHA 2 DS 2 VASc score had a poor discriminative accuracy for stroke at 30-days in CA-AF (AUC 49%, 95%CI 47%-51%, p=0.54). The machine learning autoscore integrative model revealed that the predictive ability of our newly proposed E-CHADS score (end-stage renal disease (ESRD), congestive heart failure, hypertension, active cancer, dementia, and diabetes mellitus) for 30-day risk of ischemic stroke in CA-AF was excellent (for a cutoff of 52 points random forest score) with an AUC of 80% (95%CI 74%-86%) Conclusion: Cardiac amyloidosis carries a high risk of ischemic stroke that is not accurately predicted by the CHA 2 DS 2 VASc score. Our proposed model (E-CHADS) identifies 3 new variables (ESRD, dementia, and cancer) that have higher discriminative accuracy for ischemic stroke in these patients.

Background: Catheter ablation for atrial fibrillation is a proven alternative to pharmacologic rhythm control in patients with heart failure with reduced ejection fraction (HFrEF). Whether outcomes differ in patients with heart failure with preserved ejection fraction (HFpEF) is of interest. Methods: Medline, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. We extracted or calculated a risk ratio (RR) and 95% confidence intervals (CI) from each study. Primary outcomes of interest include atrial arrythmia recurrence and repeat ablation. Harm outcomes of interest include all-cause mortality, all-cause hospitalizations, cardiovascular hospitalizations, stroke/transient ischemic attack, and cardiac tamponade. Results: We included 7 observational studies comprising 2,525 patients with HFpEF who underwent catheter ablation for atrial fibrillation. There were no significant differences in primary and harm outcomes when comparing catheter ablation for atrial fibrillation in patients with HFpEF to patients with no heart failure. Similarly, there were no significant differences in outcomes when comparing catheter ablation for patients with HFpEF to HFrEF. The certainty in these estimates was low. Conclusions: Non-randomized studies suggest that catheter ablation for atrial fibrillation in patients with HFpEF is associated with similar arrythmia free survival and safety profile when compared to patients with HFrEF and without heart failure. This suggests that patients with AF and HFpEF may benefit equally from catheter ablation as those with AF and HFrEF.