What is the immediate treatment indicated for stable Supraventricular Tachycardia (SVT)?

In the management of stable Supraventricular Tachycardia (SVT), adenosine administration is regarded as the first-line treatment option. Adenosine works by blocking the conduction through the atrioventricular (AV) node, which can interrupt the reentrant pathways that are often the cause of SVT. This action typically results in a transient pause in conduction that can restore normal sinus rhythm.

For stable SVT, the vagal maneuvers can also be effective, but the administration of adenosine is generally preferred in acute situations due to its rapid onset of action, making it a cornerstone of treatment. While vagal maneuvers play a role in managing SVT, the quick and effective action of adenosine is a significant advantage in an emergency setting.

Other options like cardioversion are usually reserved for unstable patients presenting with SVT, as it involves synchronized electrical shock. Defibrillation is inappropriate in the treatment of SVT as it is typically used for life-threatening arrhythmias, not for stable SVT. This reinforces the choice of adenosine as the immediate treatment indicated for stable SVT.