Injections of botulinum toxin A (Botox) revolutionized the beauty industry by providing a nonsurgical option for eliminating the appearance of wrinkles. Its value in treating a variety of medical conditions has since been proven, among them excessive sweating, spasticity and vocal tremors.
Now, this potent poison is poised to revolutionize treatment of atrial fibrillation (afib), a distressing type of irregular heart rhythm that can occur for many reasons.
ALBERT Y. SUN, MD, Cardiac Electrophysiology, Duke
This Treatment is an Emerging Area of Research
"In the treatment of atrial fibrillation (afib), targeting the nervous system that controls heart activity instead of the electrical system of the heart is an emerging area of research. This is akin to a mechanic fixing a car's ignition switch instead of the engine itself. This latest study investigating the effects of Botox in the control of afib in patients undergoing coronary artery bypass grafting (CABG) describes a technique to blunt the nervous system's stimulation of the heart. While it is an innovative and potentially novel treatment for postoperative afib, it is important to point out that this treatment is still in its infancy and is only currently applicable in the setting of major cardiac surgery. For the majority of people with afib, which affects approximately five million people worldwide, current treatments, including medications, lifestyle modification, and minimally invasive cardiac ablation, will continue to be the standard of care for the coming future."
Earlier Treatments Not Always Optimum.
Medications are not always successful in preventing the arrhythmia, particularly when it occurs following coronary artery bypass grafting (CABG). Ablation can be more successful, but the procedure is invasive and expensive, and more than one treatment is often needed to banish the arrhythmia.
This is where Botox may have a lead. It appears to be more effective than either alternative, with minimal cost and effort.
At the Annual Meeting of the Heart Rhythm Society in May 2015, researchers presented some astonishing results of a small study. Participants were 60 patients who experienced afib from time to time, and who were undergoing ABG. Researchers divided them into two groups. The first group received Botox injections into the fat surrounding their heart during the CABG surgery; the second group received injections of saline.
One month later, only seven percent of the Botox-treated patients had developed afib, compared to 30 percent of the placebo patients. But the big surprise came over the next 11 months, when afib recurred in 27 percent of placebo patients, but in none of the Botox patients.
The researchers expected Botox's effects to wear off between three and six months after the injection, and were surprised at how long its effects lasted. At present, they can only postulate why it happened.
Business as Usual.
The clinical trial was too small to change practice, and it will be a while before the long-term effects of Botox injections into the heart are known. Nevertheless, the researchers called their finding "potentially gamechanging."