Management of Supraventricular Tachycardia with Aberrancy

Critical First Step: Distinguish Hemodynamic Stability

The American Heart Association recommends treating supraventricular tachycardia with aberrancy as ventricular tachycardia until proven otherwise, and if the patient is hemodynamically unstable, proceeding immediately to synchronized cardioversion at 50-100J 1, 2
Hemodynamically unstable patients (hypotension, altered mental status, shock, chest pain, acute heart failure) should proceed directly to synchronized cardioversion without delay, as recommended by the American College of Cardiology 1, 3, 2
Hemodynamically stable patients have time for diagnostic evaluation and stepwise pharmacologic intervention, according to the American Heart Association 1, 2

Synchronized cardioversion is mandatory and should be performed immediately without attempting vagal maneuvers or pharmacologic therapy first, as stated by the American College of Cardiology 1, 3, 2
The initial energy for synchronized cardioversion should be 50-100J for supraventricular tachycardia, as recommended by the American Heart Association 2
The success rate of synchronized cardioversion is essentially 100% in restoring sinus rhythm, according to the American College of Cardiology 3, 2

Obtaining a 12-lead ECG during tachycardia is essential before administering any AV nodal blocking agents, as recommended by the American Heart Association 2, 4
The ECG should identify QRS duration >120 ms (confirms wide-complex tachycardia), evidence of pre-excitation or accessory pathway conduction, and regularity of rhythm, according to the American College of Cardiology 2, 3, 2
Vagal maneuvers, such as the modified Valsalva maneuver, have a success rate of 31-43% and are a safe initial intervention that avoids medication risks, as stated by the American Heart Association 2, 4
Adenosine 6 mg IV rapid bolus through a proximal/large vein, followed immediately by saline flush, is recommended if vagal maneuvers fail, with a success rate of 90-95% for AVNRT/AVRT, according to the American College of Cardiology 2, 4

If the wide-complex tachycardia is irregular and pre-excited atrial fibrillation is suspected, immediate synchronized cardioversion is recommended for hemodynamically unstable patients, as stated by the American Heart Association 3, 2
For hemodynamically stable patients, ibutilide or IV procainamide are the drugs of choice, which slow conduction over the accessory pathway and may terminate atrial fibrillation, according to the American College of Cardiology 3, 2

After successful cardioversion, patients often have atrial or ventricular premature complexes that may reinitiate tachycardia, and an antiarrhythmic drug may be required to prevent acute reinitiation, as recommended by the American Heart Association 3
Arranging cardiology follow-up for consideration of catheter ablation (94.3-98.5% single-procedure success rate) to prevent recurrence is recommended, according to the American College of Cardiology 4