Catheter Ablation for AF: Fewer Strokes, Deaths, and HF Hospitalizations

Compared with medical therapy, rhythm control with catheter ablation is associated with lower risk of ischemic stroke after 30 days, as well as less mortality and heart failure (HF) hospitalization, in patients with atrial fibrillation (AF), according to results from a new a meta-analysis.

Over 12 months of follow-up, the absolute reduction in risk for ischemic stroke with catheter ablation compared with control therapy was 0.7%. The benefits of catheter ablation were similar regardless of type of ablation (radiofrequency or cryoablation) or type of AF (paroxysmal or persistent). Surgical ablation, on the other hand, also reduced risks of stroke but was not associated with any other benefits.

In the first 30 days, though, the risk of ischemic stroke was higher with catheter ablation than with medical therapy: 0.5% vs 0.1%.

“As hypothesized, catheter ablation reduced the risk for ischemic stroke at more than 30 days, but it also increased the risk for ischemic stroke at or before 30 days,” write Bryce Montané, MD (Washington University in St. Louis, MO), and colleagues in the paper published last week in Annals of Internal Medicine. According to the study authors, the increased stroke risk may be due to endothelial trauma caused by the catheter during the procedure, resulting in the occurrence of paradoxical emboli.

A sicker population may explain why nonstroke benefits were not seen in the surgical population, they add, noting that the surgical analysis also was underpowered to determine whether ablation prevented HF hospitalizations.

Overall, the findings “suggest that catheter ablation provides durable benefits, especially in patients with HF,” Montané and colleagues say

Luigi Di Biase, MD, PhD (Montefiore Hospital, Bronx, NY), who commented on the results for TCTMD, noted that the combination of improved technology and use of uninterrupted anticoagulation have contributed to lowering stroke risk significantly during catheter ablations.

“There’s always a procedural risk, and over the years we have minimized this,” he said. “The risk is never going to be zero, . . . so the caveat when talking to patients is that catheter ablation is better, but there is some risk of stroke during the procedure.”

DiBiase emphasized that in his experience, the majority of the strokes that do occur with catheter ablation are transient ischemia attacks and are nondisabling. That information often is important in discussions with patients who could require repeat ablation procedures, he added.

“For them to know that [they] can have a better outcome with an easier recovery [compared to surgical ablation], I think it’s very important to convey that,” he said.

Compelling Reasons to Embrace Catheter Ablation

The meta-analysis included 63 RCTs published between 2001 and 2024 with a total of 11,161 patients and a median follow-up of 12 months. Of these, 39 trials compared catheter ablation and control therapy, while 24 trials compared surgical ablation and cardiac surgery without ablation. In trials of catheter ablation, control therapy consisted of antiarrhythmic agents and/or electrical cardioversion. With surgical ablation, all patients underwent the same type of cardiac surgery and were randomly assigned to additional ablation or surgery alone.

Compared with controls, patients who received catheter ablation had a higher risk of ischemic stroke prior to 30 days (RR 6.81; 95% CI 1.56-29.8). But they had a lower risk of ischemic stroke (RR 0.63; 95% CI 0.43-0.92) at 30 days and beyond, as well as reductions in total risk for ischemic stroke (RR 0.77; 95% CI 0.55-1.09) and strokes of any cause (RR 0.77; 95% CI 0.57- 1.05). Similarly, total mortality (RR 0.73; 95% CI 0.60-0.88), all-cause mortality beyond 30 days (RR 0.73; 95% CI 0.60-0.88) and HF hospitalization (RR 0.68; 95% CI 0.55-0.85) were lower compared with medical therapy.

The rates of ischemic stroke at or before 30 days after surgical ablation were lower (RR 0.56; 95% CI 0.21-1.46) when compared with no ablation. Surgical ablation also reduced the risk of ischemic stroke (RR 0.54; 95% CI 0.34-0.86) and strokes of any cause (RR 0.54; 95% CI 0.35-0.82).

According to Montané and colleagues, the reduction in HF hospitalization is an important finding that suggests that controlling atrial contractions may factor into keeping patients out of the hospital.

In an editorial accompanying the study, Jonathan W. Waks, MD, and Peter Zimetbaum, MD (both Beth Israel Deaconess Medical Center, Boston, MA), say the results of the meta-analysis provide further evidence that rhythm control with ablation has significant benefits for patients with AF.

However, they note that trials of pulsed field ablation, a newer technology that is being widely adopted, were not included in this analysis.

Waks and Zimetbaum say that while the reduction in stroke risk is a compelling reason to embrace catheter ablation for rhythm control, this “should not be interpreted as a reason to discontinue thromboembolic prophylaxis if it is otherwise indicated based on guidelines.”

DiBiase also added a caution, noting that 10 of the 39 trials of catheter ablation in this analysis focused primarily on patients with HF, so the mortality data are weighted toward those patients more so than those with AF only.

“So, the mortality data may not be as strong as some of the other outcomes, but it is there and it should be acknowledged,” he said.

While beyond the scope of this investigation, DiBiase also stressed the importance of early rhythm control and its role in the management of AF, which was emphasized in the most recent clinical practice guideline.

Indeed, Montané and colleagues note that in EAST-AFNET 4, early rhythm control with catheter ablation, antiarrhythmic drugs, or cardioversion reduced the risk of both death and stroke, suggesting that attacking the arrhythmia early may help stave off downstream CV events. Unlike the meta-analysis, however, EAST-AFNET 4 did not show a reduction in HF hospitalization with rhythm control.