The European Society of Cardiology (ESC) Guidelines on supraventricular tachycardia have been published in the European Heart Journal, and on the ESC website.
Supraventricular tachycardia (SVT) refers to a heart rate above 100 beats per minute (normal resting heart rate is 60 to 100). It occurs when there is a fault with the electric system that controls the heart’s rhythm. SVTs are frequent arrhythmias, with a prevalence of approximately 0.2% in the general population. Women have a risk of developing SVT that is two times greater than men, while people 65 years or older have more than five times the risk of developing SVT than younger people.
SVTs usually start and stop suddenly. They arise in the atria of the heart and the conduction system above the ventricles, and are rarely life-threatening in the acute phase, unlike arrhythmias from the ventricles. However, most SVTs, if left untreated, are lifelong conditions that affect the heart’s function, increase the risk of stroke, and affect quality of life. Symptoms include palpitations, fatigue, light-headedness, chest discomfort, shortness of breath, and altered consciousness.
The guidelines provide treatment recommendations for all types of SVTs. Drug therapies for SVT have not fundamentally changed since the previous guidelines were published in 2003.
But Professor Josep Brugada, Chairperson of the guidelines Task Force and professor of medicine, University of Barcelona, Spain, said: “We do have more data on the potential benefits and risks associated with several drugs, and we know how to use them in a safer way. In addition, some new antiarrhythmic drugs are available.”
Antiarrhythmic drugs are useful for acute episodes. For long-term treatment these drugs are of limited value due to relatively low efficacy and related side-effects.
The main change in clinical practice over the last 16 years is related to the availability of more efficient and safe invasive methods for eradication of the arrhythmia through catheter ablation. This therapy uses heat or freezing to destroy the heart tissue causing the arrhythmia.
Professor Demosthenes Katritsis, Chairperson of the guidelines Task Force and director of the 3rd Cardiology Department, Hygeia Hospital, Athens, Greece, said: “Catheter ablation techniques and technology have evolved in a way that we can now offer this treatment modality to most of our patients with SVT.”
SVT is linked with a higher risk of complications during pregnancy, and specific recommendations are provided for pregnant women. All antiarrhythmic drugs should be avoided, if possible, within the first trimester of pregnancy. However, if necessary, some drugs may be used with caution during that period.
“Pregnant women with persistent arrhythmias that do not respond to drugs, or for whom drug therapy is contraindicated or not desirable, can now be treated with catheter ablation using new techniques that avoid exposing themselves or their baby to harmful levels of radiation,” said Prof Katritsis.
What should people do if they experience a fast heartbeat? “Always seek medical help and advice if you have a fast heartbeat,” said Prof Brugada. “If SVT is suspected, you should undergo electrophysiology studies with a view to catheter ablation, since several of the underlying conditions may have serious long-term side effects and inadvertently affect your wellbeing. Prevention of recurrences depends on the particular type of SVT, so ask your doctor for advice. Catheter ablation is safe and cures most SVTs.“