Cautious Optimism

I shared a cab ride with a cardiologist training in electrophysiology while I was attending the American College of Cardiology scientific session in Washington, D.C. Talk about being in the right place at the right time.

Our cover story deals with catheter ablation as a treatment for paroxysmal atrial fibrillation, a procedure my fellow passenger and I discussed during our ride to the conference center. Electrophysiologists have options in the energy source for an ablation, with radiofrequency and cryoballoon serving as two pathways. Each offers benefits and limitations, and technical advancements on both fronts may help facilitate ablations and improve outcomes. 

The field of catheter ablation has matured over the years, and experienced electrophysiologists say they have a good idea which patient populations are likely to benefit. My cab companion is entering a field with a scientific foundation and opportunity for growth.

Nonetheless, researchers have not yet provided reliable evidence that ablation reduces the risk of stroke, despite a reduction in recurrence of arrhythmias compared with medical therapy. Large randomized trials are under way that may settle the issue.

Renal denervation, another catheter-based procedure, is still in its infancy. It also treats a condition that carries morbidity and mortality risk: treatment-resistant hypertension. With SYMPLICITY HTN-3 failing to meet its efficacy endpoint, renal denervation could be a bust.

This issue also looks at the future of renal denervation post-HTN-3. The negative results are not likely to be the final chapter, though. The ending could be one of success or failure.

My companion’s first-hand witnessing of the renal denervation letdown may be a valuable lesson. It seems logical that by making patients atrial fibrillation-free, ablation also would reduce their risk of stroke. But until it is proven, it should be couched—as many had said about renal denervation—as cautious optimism.