Hybrid Ablation for Stubborn AFib
Many options are currently available for treating atrial fibrillation (also called AFib or AF), but this heart rhythm disorder can remain stubbornly persistent for some patients. Interest has been growing in a potential treatment option for those patients: hybrid ablation.
The approach attempts to combine the best of two established procedures, catheter ablation and surgical ablation, and it has shown some promise for tough-to-manage atrial fibrillation. But the evidence comes from small studies, and the role of hybrid ablation in treating atrial fibrillation remains unclear. Here is what’s known so far.
Atrial fibrillation basics
First, it’s helpful to understand the different forms of atrial fibrillation:
• Paroxysmal. Episodes of fibrillation begin suddenly, then stop within a week, with or without intervention; they may return frequently or only periodically.
• Persistent. Continuous atrial fibrillation for more than a week.
• Long-standing persistent. Continuous atrial fibrillation that lasts longer than one year.
People who fall into any of those categories may need treatment to maintain a normal heart rhythm. Generally, rhythm-controlling medications are the first choice. But when drugs fail (or cause too many side effects), another option is ablation. This procedure uses an energy source (usually radio waves) to create scar tissue in strategic locations on the heart. The scar tissue disrupts the faulty electrical signals causing the arrhythmia.
While ablation often helps patients with paroxysmal atrial fibrillation, it does not work as well against persistent atrial fibrillation—especially if the condition is long-standing. This is where treatment with hybrid ablation could, theoretically, fit in.
Catheter vs. surgical ablation
Most often, ablation is performed through an electrode-tipped catheter that is threaded through a blood vessel into the heart. It can also be accomplished with minimally invasive surgery, with the surgeon making small incisions in the sides of the chest, allowing a camera-carrying scope, instruments, and an ablation device to be passed through to the heart’s surface.
A key difference between the two procedures is this: Catheter ablation is performed within the heart, while surgical ablation is performed on the heart’s surface. Thus, each approach allows access to different heart structures.
Each procedure has its own advantages. Catheter ablation often uses advanced technologies such as 3-D mapping, which helps ensure there are no gaps along the scar tissue that’s created. Gaps could allow erratic electrical signals to continue, triggering AFib episodes.
Surgical ablation, meanwhile, allows the doctor to clamp off a pouch called the left atrial appendage, which can lower the risk of a future stroke.
The idea behind hybrid ablation is that the two techniques combined might work better than either alone—particularly for people with persistent atrial fibrillation, where the underlying electrical abnormalities may be more complicated.
The hybrid approach
Hybrid ablation is still investigational, though some medical centers offer the procedure. The specifics vary among centers that do perform hybrid ablation. Often, it’s done in two steps: surgical ablation first, followed by catheter ablation days to weeks later. At that point, the heart’s electrical activity is tested, and the catheter can be used to “touch up” any gaps in the scar tissue.
So far, researchers have had some encouraging results. One study published in the Journal of the American Heart Association focused on 50 patients with long-standing atrial fibrillation that had not responded to drug treatment. All patients underwent hybrid ablation, and one year later, 94 percent were atrial fibrillation-free (although four patients still needed medication).
Other small studies have had similar results. A review of nine studies found that anywhere from about 37 to 92 percent of patients were atrial fibrillation-free and off antiarrhythmic medications six months after having hybrid ablation. In most of the studies, that figure was over 70 percent.
There are risks involved, however. A few deaths were reported, and some patients suffered bleeding, collapsed lungs, and fluid buildup around the heart or lungs. Also, if the procedure is done in two steps, that means two hospitalizations and an extra recovery period.
For now, hybrid ablation is not among the atrial fibrillation treatments recommended by the American Heart Association/American College of Cardiology. Studies have been small and short-term, and while the patients involved have usually had persistent atrial fibrillation, they have typically been relatively healthy and in their 50s or 60s.
What’s more, no large, controlled trials have yet tested hybrid ablation against catheter ablation. However, one 2016 study found a discouraging pattern: It compared 24 patients with long-standing atrial fibrillation who opted for hybrid ablation with 35 who chose catheter. The hybrid patients suffered more complications. Two years later, only 19 percent of the hybrid ablation patients were arrhythmia-free after a single procedure, compared with 54 percent of catheter-ablation patients.
Still more needs to be learned about hybrid ablation before it can be widely used. If you have persistent atrial fibrillation that does not improve with medication, catheter ablation may be an option. If that fails, a repeat ablation can sometimes be effective. Talk with your doctor to determine the approach that’s best for you.