By Michael H. Crawford, MD
Synopsis: An observational study from China in older patients with persistent atrial fibrillation (AF) has shown that an earlier diagnosis to catheter ablation time of ≤ 12 months compared to > 12 months is associated with lower rates of AF recurrence and adverse cardiovascular outcomes.
Source: Wang S, Guo J, Song Z, et al. Association between diagnosis-to-ablation time and postablation outcomes in older patients with persistent atrial fibrillation. JACC Adv. 2025; Oct 15. doi: 10.1016/j.jacadv.2025.102248. [Online ahead of print].
Several studies have suggested that an early rhythm control strategy for patients with persistent atrial fibrillation (AF) reduces recurrences and increases quality of life (QOL). Thus, these investigators from Shanghai, China, hypothesized that the diagnosis of AF to ablation time (DAT) divided at one year would be an independent risk factor for recurrences and adverse outcomes in older patients with persistent AF.
Between 2020 and 2022, the investigators conducted a multicenter observational study of the effect of DAT on post-ablation outcomes in this population. They recruited patients 65-80 years of age with persistent AF and symptoms refractory to at least one antiarrhythmic agent. Excluded were patients with a history of catheter ablation (CA), cardiac surgery, severe valve disease, or structural heart disease, and those with a life expectancy of < 12 months. DAT was defined as the interval between the documented AF diagnosis and the ablation procedure.
The patients were stratified into two groups: early DAT (≤ 12 months) and late DAT (> 12 months). They had follow-up visits at three months, 12 months, and every six months thereafter that included an electrocardiogram (ECG) and a 24-hour Holter monitor. The primary outcome was a composite of freedom from recurrent AF episodes of > 30 sec duration without antiarrhythmic drug therapy (ADT) after a three-month blanking period on oral anticoagulants, adverse cardiovascular (CV) outcomes (such as death), CV hospitalization (CVH), and ischemic stroke.
The investigators enrolled 587 patients (mean age 71 years, 61% men), 332 in the early CA group and 255 in the late CA group. DAT was performed significantly earlier in the early group compared to the late group (6 vs. 60 months, P < 0.001). Patients in the early group were older than those in the late group (71 vs. 64 years of age, P < 0.001). There were no other significant clinical or echocardiographic differences between the groups.
After 24 months of follow-up, recurrent AF occurred in 32% of the early DAT group and in 41% of the late DAT group (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.52-0.91; P = 0.005). Adverse CV outcomes were found in 22% of early DAT patients and in 35% of late DAT patients (HR, 1.70; 95% CI, 1.23-2.34; P = 0.001). Also, CVH was significantly higher in the late group (HR, 1.57; 95% CI, 1.10-2.26; P = 0.001). However, stroke and death were not significantly different between the two groups.
Sensitivity analyses showed that left atrial dimension on echocardiography was significantly related to AF recurrence (HR, 1.05; 95% CI, 1.02-1.07; P < 0.001). The authors concluded that in older patients with persistent AF, DAT ≤ 12 months was associated with lower AF recurrence rates and adverse outcomes. Thus, early CA may improve clinical outcomes in this population.
Commentary
AF is more common in patients 65 years of age and older, and such patients are at higher risk for CV disease and ischemic stroke. Previous studies have shown that rhythm control often is the preferred strategy since it reduces recurrence rates. It is well known that AF recurrences are strongly associated with increased symptoms, reduced QOL, and increased healthcare use.
If CA is chosen for rhythm control, the issue is what the optimal timing should be. This observational study from China studied older AF patients with AF refractory to at least one antiarrhythmic drug. The authors chose to test CA in ≤ 12 months vs. later. They showed that a shorter DAT time was associated with lower AF recurrence rates and adverse CV outcomes. Death and stroke were not significantly reduced as single outcomes, but their frequency was low in this study and there was a trend in this direction.
There are limitations to this study to consider. First, it is observational, so there could be unmeasured confounders that could reduce any causal implications. Second, the time of AF recurrence documentation may have been later than symptom onset. Third, it is unclear if these results would apply to younger patients. Fourth, there was a big difference in the timing of CA between the two groups (6 vs. 60 months), which suggests that other factors not accounted for affected the time of CA. Finally, AF recurrence was not assessed by an implantable loop recorder, so AF recurrences may have been underestimated.
This study has several implications. An early referral to electrophysiology specialists is warranted in older persistent AF patients. Also, the association of left atrial size with recurrences suggests that imaging to stratify the patient’s suitability for CA is important. In addition, early CA can reduce healthcare costs and improve QOL.
Michael H. Crawford, MD, is Professor Emeritus of Medicine and Consulting Cardiologist, UCSF Health, San Francisco.