What is the priority treatment for a patient experiencing unstable SVT?

The priority treatment for a patient experiencing unstable Supraventricular Tachycardia (SVT) is cardioversion. In unstable SVT, the patient may be experiencing symptoms such as hypotension, altered mental status, angina, or signs of heart failure, which signifies that immediate intervention is necessary to restore a normal heart rhythm and stabilize the patient.

Cardioversion is a controlled procedure where an electrical shock is delivered to the heart to reset the rhythm back to normal. This is particularly important in unstable cases, as it helps to quickly alleviate symptoms and prevent further complications associated with sustained tachycardia.

While adenosine can be used to treat SVT by slowing down conduction through the AV node and can sometimes convert SVT to a normal rhythm, it is generally used in stable patients. Digitalis is used to increase cardiac contractility and rate control over time, which is not appropriate for immediate stabilization in an emergency setting. Defibrillation is indicated for life-threatening arrhythmias such as ventricular fibrillation and not for unstable SVT, highlighting why cardioversion is the most critical intervention in this scenario.