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Background Incident heart failure (HF) is the most common non-fatal event in patients with atrial fibrillation (AF), although strategies for HF prevention are lacking. Objectives To identify modifiable risk factors and estimate the impact of risk factor modification on HF risk in women with new-onset AF. Methods We assessed 34 736 participants in the Women’s Health Study free of prevalent cardiovascular disease at baseline. Cox models with time-varying assessment of risk factors after AF diagnosis were used to identify significant modifiable risk factors for incident HF. Results Over a median follow-up of 20.6 years, 1495 women developed AF without prevalent HF. In multivariable models, new-onset AF was associated with an increased risk of HF (HR 9.03 [95% CI: 7.52-10.85]). Once women with AF developed HF, all-cause (HR 1.83 [1.37-2.45]) and cardiovascular mortality (HR 2.87 [1.70-4.85]) increased. In time-updated, multivariable models accounting for changes in risk factors after AF diagnosis, systolic blood pressure > 120 mmHg, body mass index ≥ 30 kg/m2, current tobacco use, and diabetes mellitus were each associated with incident HF. The combination of these 4 modifiable risk factors accounted for an estimated 62% [23-83] of the population attributable risk of HF. Compared to women with 3 or 4 risk factors, those who maintained or achieved optimal risk factor control had a progressive decreased risk of HF (HR for 2 risk factors: 0.60 [0.37-0.95], 1 risk factor: 0.40 [0.25-0.63], 0 risk factors: 0.14 [0.07-0.29]). Conclusion In women with new-onset AF, modifiable risk factors including obesity, hypertension, smoking, and diabetes accounted for the majority of the population risk of HF. Optimal levels of modifiable risk factors were associated with decreased HF risk. Prospective assessment of risk factor modification at the time of AF diagnosis may warrant future investigation.

Background-In the treatment of patients with refractory atrial fibrillation (AF), the safety and efficacy of atrioventricular nodal ablation (AVNA) versus pharmacotherapy alone remains unclear. Additionally, the impact of AVNA in patients with reduced systolic function is of growing interest. Methods and Results-A total of 5 randomized or prospective trials were included for efficacy review (314 patients), 11 studies for effectiveness review (810 patients), and 47 studies for safety review (5632 patients). All-cause mortality was similar between AVNA and medical therapy (3.1% versus 3.3%; relative risk ratio, 1.05; 95% confidence interval [CI], 0.29 -3.85). There was no significant difference in exercise duration or ejection fraction (EF) with AVNA relative to pharmacotherapy. In subgroup analysis, patients with baseline systolic dysfunction (116 patients; mean EF, 44%) showed significant relative improvement in EF after AVNA (ϩ4% greater; 95% CI, 3.11-4.89). In pooled observational analysis, AVNA was also associated with significant improvement in EF only in patients with systolic dysfunction (ϩ7.44%; 95% CI, 5.4 -9.5). The incidence of procedure-related mortality (0.27%) and malignant arrhythmia (0.57%) was low. At mean follow-up of 26.5 months, the incidence of sudden cardiac death after AVNA was 2.1%. There was significant heterogeneity in quality-of-life scales used; compared with pharmacotherapy, AVNA was associated with significant improvement in several symptoms (palpitations, dyspnea). Conclusions-In the management of refractory AF, AVNA is associated with improvement in symptoms and quality of life, with a low incidence of procedure morbidity. In patients with reduced systolic function, AVNA demonstrates small but significantly improved echocardiographic outcomes relative to medical therapy alone. (Circ Arrhythm Electrophysiol. 2012;5:68-76.)