Supraventricular tachycardia (SVT) refers to abnormal regular rapid heart rhythms that originate in the upper chambers of heart. There are many causes but usually this is caused by an abnormal circuit in the heart (i.e. reentry) or by irritable heart tissue in the atria firing rapidly. As a result, many types of SVT are possible. Often the exact SVT diagnosis is not determined unless catheters are placed in the heart and the electrical wiring is studied with a procedure called an EP (electrophysiology) study.
Patients with SVT may feel palpitations, lightheadedness, shortness of breath, chest pain, and occasionally may lose consciousness.
Although medications can sometimes be used to control these rhythms, cardiac ablation is often recommended as it may offer a potentially curative option. During the SVT ablation procedure, an EP study is performed first to determine the exact type, mechanism, and location of SVT. Once this is determined, ablation is performed to rectify the problem.