Atrial fibrillation (A-fib) is the most common arrhythmia in adults — more than 8 million Americans have some classification of A-fib. Of those, researchers estimate about 70% have either persistent A-fib or long-standing persistent A-fib. “A-fib is a serious and growing problem in this country, with over a million cases diagnosed annually,” said Kent E. Morris, M.D., electrophysiologist with Norton Heart & Vascular Institute. “It does carry with it a significantly increased risk of stroke, as well as an increased risk of heart failure. Unaddressed, it certainly can lead to an increase in mortality.”

Recent developments in the treatment for this abnormal heart rhythm include understanding the importance of early rhythm control and the role that catheter ablation and hybrid ablation play in this approach.

Classifications of atrial fibrillation

• Paroxysmal atrial fibrillation is self-limiting and lasts less than seven days. Patients convert spontaneously back to normal rhythm.
• Persistent atrial fibrillation is an episode that lasts longer than seven days or requires some sort of intervention to restore normal sinus rhythm.
• Long-standing persistent atrial fibrillation is defined as continuous atrial fibrillation for longer than one year in duration.
• Permanent atrial fibrillation is defined clinically when the goal of treatment is no longer the restoration of sinus rhythm.

Chronic atrial fibrillation is an older term still used frequently, but it really doesn’t fit into the current classification.

Paroxysmal A-fib vs. long-standing persistent A-fib

These two classes of patients present differently, and it can be unclear at initial presentation into which class they will fall. In paroxysmal A-fib  patients, classic symptoms include a feeling of the heart beating out of the chest, palpitations and the feeling of fluttering. These patients tend to be very acutely symptomatic.

In patients with persistent and long-standing persistent atrial fibrillation, their symptoms are often somewhat vague, though not necessarily less severe. These include fatigue, exertional intolerance, shortness of breath with exertion and decreased energy levels.

“They still may have palpitations at times, but typically the symptoms are more of these other sorts of things like the fatigue, decreased energy, weakness,” Dr. Morris said. “Because these symptoms are not specific to long-standing atrial fibrillation, they often get blamed on myriad other things.”

Comorbidities in long-standing persistent a-fib

There are a number of changes a patient can make to affect their abnormal heart rhythm, including:

• Stopping smoking
• Losing weight
• Addressing sleep issues such as sleep apnea
• Getting enough physical activity
• Addressing high blood pressure
• Reducing or eliminating alcohol intake
• Adequately controlling diabetes mellitus

A hybrid approach to treating persistent A-fib

For the last two decades, catheter ablation via pulmonary vein isolation has been the typical treatment for symptomatic atrial fibrillation that has not responded to antiarrhythmic drug therapy. While effective in some classifications of A-fib, standalone pulmonary vein isolation is not adequate for the advanced long-standing persistent atrial fibrillation patient.

Norton Heart & Vascular Institute offers a Hybrid ablation procedure for A-fib patients with long-standing, persistent symptoms who either are not suitable for standard catheter ablation or have had unsuccessful ablations in the past.

The Hybrid ablation procedure combines epicardial and endocardial ablation. The procedure is performed in two stages. First, Steven M. Peterson, M.D., cardiothoracic surgeon, Norton Cardiothoracic Surgery, performs the epicardial ablation along the posterior left atrial wall. About six weeks later, a cardiac electrophysiologist performs an endocardial ablation.

Patients who have long-standing persistent A-fib and continue to be symptomatic are ideal candidates for the Hybrid ablation procedure.

“This procedure offers a better chance for success for patients who didn’t have many options before,” Dr. Peterson said. “A full thickness burn gives us the best chance of eliminating all the potential triggers of atrial fibrillation.”

The surgical portion of a Hybrid ablation procedure involves making an incision the width of two fingertips underneath the rib cage. The surgeon then uses radiofrequency energy to ablate the epicardial surface of the posterior left atrium.

For the ablation inside the heart, the electrophysiologist inserts a catheter in the groin and then through a transseptal approach maps and ablates inside the left atrium to complete the procedure.

Hybrid Ablation clinical trial

In 2020, the results of the CONVERGE-IDE clinical trial were released, which demonstrated superior effectiveness utilizing a hybrid ablation approach compared to standalone catheter ablation for the treatment of persistent and long-standing persistent atrial fibrillation.

Who is a candidate for a hybrid ablation for their irregular heart rhythm?

“They tend to be persistent or long-standing persistent atrial fibrillation patients,” Dr. Morris said. “Most have moderate to severe left atrial enlargement. Some have had endocardial ablations that failed to manage the irregular heart rhythm. Some of them have not had prior ablations.”

Contraindications include:

• Prior sternotomy
• History of cardiac surgery or mediastinal radiation, which can make it difficult to identify the correct anatomy and access it
• Left atrial appendage thrombus
• Significant coronary or valvular heart disease which might require surgery

Improved outcomes with hybrid ablation

Approximately 250 Norton Heart & Vascular Institute patients have undergone the Hybrid ablation procedure since we began our program in 2017.

“The most recent data shows that our success rate right now is around 80% for one year, remaining in sinus rhythm,” Dr. Morris said. “A fair portion no longer need antiarrhythmic drug therapy, and some patients are able to stop blood thinners.”

“Five or 10 years ago we didn’t have this kind of treatment available for abnormal heart rhythm condition. I think it’s been a game-changer as far as being able to help people return to their quality of life and improve the way they feel.”