Supraventricular Tachycardia

ECG Findings:

1. A run of at least 4 supraventricular premature beats in a row (see above).
2. Often occurs as paroxysms (bursts).

Etiology: The same as for supraventricular premature beats (see above)

Consequences: Paroxysms of supraventricular tachycardia can result in weakness, syncope, and heart failure when sustained and untreated

Treatment:

1. Efforts to increase the parasympathetic tone and thereby reduce A-V nodal conduction may be useful in slowing the ventricular response, assisting in detecting atrial activity (P waves on ECG), and differentiating supraventricular tachycardia from ventricular tachycardia. This may be accomplished by:
   • Vagal maneuvers such as ocular pressure or carotid sinus massage
   • Reflex induced increase in vagal tone using phenylephrine
2. Anti-arrhythmics including beta blockers (e.g. propranolol, metoprolol, atenolol), calcium channel blockers (diltiazem), sotalol, or digoxin.