Abstract Body (Do not enter title and authors here): Background: While atrial fibrillation (AF) clinical trials define treatment success by time to first AF episode > 30 seconds, our previous survey identified patient-defined success as a Toronto AF Severity Score (AFSS) of ≤ 5 (no-mild symptoms, 80% of participants) and an AF episode lasting ≤ 1 hour (60% of respondents). Our objective is to better understand patterns of AF treatment success and failure when defined by patient priorities.

Methods: Using an institutional retrospective cohort of AF patients with either AFSS scores (53.8%) and/or ambulatory ECG (AECG) data (59.4%), we describe the proportion of patients failing to achieve an AFSS ≤ 5 or AF episodes ≤ 1 hour (Figure 1).

Results: Between 2019 and May 2024, 2087 patients with an AFSS symptom score, and 2305 with AECG monitoring were included, of whom 862 (41%) had AFSS scores ≤5 and 1130 (49%) had AF episodes ≤1 hour. Compared to patients with AFSS ≤ 5, 1225 patients (59%) with AFSS > 5 were younger, more likely to be female, and have more comorbid conditions (hypertension, diabetes mellitus, obstructive sleep apnea, and heart failure) without significant differences in treatment, including rhythm control strategies (Table 1). Compared to patients with AF episodes ≤ 1 hour, 1175 patients (51%) with AF episodes > 1 hour were more likely to have received prior ablation, prior cardioversion, and anti-arrhythmic medications.

Conclusion: Less than half of AF patients in clinical practice have AF symptom scores or arrhythmia burdens meeting patient-defined goals, with significant differences in both success measures by patient characteristics. Pursuing goal-oriented treatment in AF research and care may help clinicians identify uncontrolled patients, align treatment to patient priorities, and direct future medical intervention at an individual level.