Everyone at least once in his or her life has experienced changes in heart rhythm and rate: palpitations, heart skipping beats or vice versa - extra beats, etc. The medical term for such conditions is arrhythmia. There are many types of arrhythmia including physiological tachycardia, premature (or extra) beats, bradycardia, atrial fibrillation, paroxysmal supraventricular tachycardia, atrial flutter, ventricular tachycardia and ventricular fibrillation. They can be genetically conditioned or provoked by overuse of drugs, alcohol or smoking as well as underlying diseases including cardiovascular ones.
Some of these arrhythmias are natural and harmless; for example, physiological tachycardia (a heart rate over 100 beats per minute) is a normal response of the body to any physiological (exercise, strenuous physical activity) or psychological stress. In this case, the increased heart rate is temporary, it restores to its normal numbers once the stress is over. Others, however, are quite dangerous (atrial fibrillation, for example) and can be even life-threatening (paroxysmal supraventricular tachycardia).
The influence of stress and anxiety on the health of the cardiovascular system is well recognized. Both acute and chronic stressors are associated with increased arrhythmic risk. Emotional stress that overexcites the nervous system, particularly its sympathetic-adrenal structures, causes the active release of catecholamines – adrenaline and noradrenaline – that disrupt the heart rate provoking arrhythmias such as tachycardia and extrasystoles. Acute emotional stress can lead to the contractile dysfunction of the left ventricle, myocardial ischemia, or disturbance of the heart rate. Although such disturbances are often short-termed, their after-effects can be sometimes fatal. Chronic stress can result in reduced variability of the heart rate, reduced sensitivity of baroreceptors and increased QT dispersion. Patients with significant changes in the neural regulation of the heart caused by stress are at the greatest risk of having fatal ventricular arrhythmias.
Not only stress, but other psychological factors are significant contributors to the development of cardiac arrhythmias. Thus, negative emotions like hostility and anger can raise the risk of atrial fibrillation and sudden emotional excitement can even provoke malignant ventricular arrhythmias.
Nonpharmacological methods of stress management in patients with or without heart diseases include yoga, relaxation therapy, controlled slow breathing, social support and meditation.