Supraventricular Tachycardia, Initial Diagnosis and Treatment When supraventricular tachycardia (SVT) causes symptoms, it requires immediate medical attention. Although many physicians believe that the precise type of SVT must be identified before providing treatment, this is not true: treatment can often be started safely and effectively without knowing the exact SVT, by tailoring it to the characteristics of the ventricular response as seen on the electrocardiogram (ECG) and history.