Final answer:
In emergency cases of hemodynamically unstable SVT, urgent cardioversion is the standard treatment to restore normal heart rhythm.
Step-by-step explanation:
If a patient with Supraventricular Tachycardia (SVT) is hemodynamically unstable, it is a medical emergency that necessitates immediate treatment. The standard intervention for an unstable patient with SVT is urgent cardioversion, which is the application of a controlled electric shock to the heart in an effort to restore a normal rhythm. In some cases, antiarrhythmic medications may be used as well. For those who are not unstable but have severe symptoms from an arrhythmia, a less urgent form of cardioversion or defibrillation may be employed, alongside medication such as thinners to reduce the risk of complications associated with arrhythmias.