by Nikhil Ramburn and Sat Bir Singh Khalsa, Ph.D.
Cardiac arrhythmias are a group of conditions characterized by an irregular heartbeat. One such condition is atrial fibrillation (AF), which affects the upper chambers of the heart (the atria). Rapid and irregular heartbeats are the primary cause of symptoms associated with AF. These symptoms include palpitations, dizziness, anxiety, and reduced exercise capacity, which eventually result in severely impaired quality of life. AF tends to progress from short episodes to longer, more frequent attacks although asymptomatic episodes are common even in patients who routinely exhibit symptoms. Common medical complications include large variations in blood pressure and an increased risk of stroke. A few lifestyle risk factors have been identified for AF, the most important one being hypertension along with obesity, alcohol, and caffeine consumption.
Despite recent advances in pharmacotherapy, ventricular arrhythmia and AF mortality rates are still high and by the age of 80 years, the lifetime risk of developing AF is approximately 22%. There is increasing epidemiological significance of AF given reports predicting a doubling of AF prevalence by 2050. The current lack of effective treatment for AF exacerbates this grim forecast. Conventional treatment is based on pharmacotherapy and ablative/surgical strategies, both of which have limitations. Antiarrhythmic drug therapy is associated with a relatively high recurrence rate and can paradoxically precipitate more ventricular arrhythmia. On the other hand, catheter ablation can effectively suppress the early stages of AF (paroxysmal AF) but is difficult to achieve with persistent AF or concomitant cardiac disease. Therefore, there is a need for integrative and complementary therapies that go beyond symptom alleviation to treat the underlying lifestyle risk factors and improve the quality of life of individuals with AF.
Yoga therapy may prove to be one such complementary treatment for AF. Yoga is especially known for its ability to affect the autonomic nervous system, including both sympathetic and parasympathetic activity, which results in a positive impact on heart rate and blood pressure. Furthermore, yoga practice has been shown to reduce stress and anxiety thereby improving quality of life for AF patients. Finally, yoga has potential efficacy in addressing underlying lifestyle risk factors, such as obesity, by improving behaviors including eating and physical activity. Yoga practice may also lead to a reduction in excessive alcohol and caffeine consumption by enhancing awareness of the physical body and providing alternative coping tools. In light of these benefits, the efficacy of yoga therapy for AF has been an attractive alternative treatment, especially since there are significantly few, if any, negative side effects and yoga is less expensive than medications or surgery.
There is now a small but growing body of clinical trial research evidence documenting the beneficial effects of yoga on patients with heart arrhythmia. A 2012 study from the Sant Gadge Baba Amravati University in India, was the first to present data on the effects of pranayama (yogic breathing) on markers of myocardial (heart tissue) electrical instability. Researchers evaluated 27 patients after a 12-week program of 36 pranayama sessions. The intensity of the exercises was modified and all participants were successful in completing the pranayama intervention. The results showed numerous promising improvements in cardiovascular health. For example, exercise capacity increased by 25% and the indices of ventricular electrical repolarization dispersion (a marker of heart tissue malfunction) was markedly reduced. This last finding indicates a significant decrease in the patients’ risk of having ventricular dysrhythmia and sudden cardiac-induced death. These marked improvements suggest that more traditional forms of yoga that include pranayama should be considered in clinical yoga therapy applications.
The first study to examine the impact of yoga in patients with AF was published in 2013 in the prestigious Journal of the American College of Cardiology. Researchers from the University of Kansas Hospital and Medical Center evaluated at 53 patients with paroxysmal AF who were between 18 and 80 years old. All patients received Iyengar yoga training for 60 minutes at least twice weekly and sessions consisted of pranayama, physical yoga exercises and relaxation. The results showed that the yoga intervention significantly reduced the number of symptomatic episodes and improved resting heart-rate and blood pressure. In addition, depression, anxiety, and quality of life scores improved significantly, thereby highlighting the efficacy of yoga in addressing the secondary impacts of AF on mental and physical health. These early findings underscore the therapeutic value of a low-cost, non-invasive behavioral treatment like yoga. Future research is needed to elucidate whether the findings are applicable to more chronic forms of AF.
A more recent study by investigators in the Divisioin of Cardiovascular Medicine at the Danderyd Hospital in Stockholm, Sweden was published in 2017. In this clinical trial, 80 patients with paroxysmal AF were randomly assigned to either a standard care control group or received standard treatment in combination with yoga for 12 weeks. The Kundalini Yoga-based intervention (Mediyoga http://en.mediyoga.com/) was adapted for individuals with cardiac diseases and included deep breathing followed by light movements, Sat Kriya, and meditation. The results showed that yoga significantly improved quality of life scores, an important outcome for this patient population. In addition, heart rate and blood pressure scores were significantly lower in the yoga group when compared to those of the control group. Since hypertension is an important risk factor for AF and most patients have poorly regulated blood pressure, these results suggest that yoga may prove to be an important complementary treatment for this condition.
Despite these encouraging preliminary findings demonstrating the efficacy and absence of significant side effects for yoga interventions in AF patients, they are based on very few trials and more studies with larger sample sizes are required to substantiate these results. Future research is also needed to elucidate some of the mechanisms underlying the markers of electrical instability in heart tissue and how yogic breathing and exercises can positively impact the abnormal electrical activity of heart cells.