In stable patients with supraventricular tachycardia (SVT), what is the first-line approach?

In stable patients with supraventricular tachycardia (SVT), the first-line approach is typically the application of vagal maneuvers. These maneuvers enhance vagal tone, which can help to interrupt the reentrant circuits responsible for most types of SVT. Common vagal maneuvers include the Valsalva maneuver and carotid sinus massage.

The reasoning behind this initial treatment strategy is that it is non-invasive, readily applicable, and can effectively terminate SVT in a significant number of patients. In many cases, vagal maneuvers will convert the arrhythmia back to a normal sinus rhythm without the need for pharmacological intervention or procedural measures, making it an ideal first step in the management of stable SVT.

If vagal maneuvers are unsuccessful, adenosine can then be administered as it works rapidly to interrupt the conduction through the AV node and terminate the arrhythmia. However, the preference for vagal maneuvers as the first approach highlights the focus on patient safety and minimizing invasive or more aggressive treatments in stable patients.