What is Supraventricular Tachycardia (SVT) with aberrancy?

From the Guidelines

Supraventricular tachycardia (SVT) with aberrancy refers to a rapid heart rhythm originating above the ventricles that conducts to the ventricles with an abnormal pattern, mimicking ventricular tachycardia. This condition occurs when the electrical impulse travels through the ventricles in an unusual way, often because one of the bundle branches is blocked or conducting slowly. The key distinction is that the origin of the rhythm is supraventricular, but the appearance on ECG may resemble ventricular tachycardia due to this aberrant conduction. Common causes include pre-existing bundle branch block, rate-related aberrancy (when the heart rate exceeds the refractory period of one bundle branch), or functional aberrancy due to premature beats. Differentiating SVT with aberrancy from ventricular tachycardia is crucial for proper treatment and can be done using criteria such as the presence of RS complexes in precordial leads, QRS duration, and specific morphology patterns, as noted in the 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia 1. Treatment typically focuses on addressing the underlying SVT with medications like adenosine (6-12 mg IV push), beta-blockers (such as metoprolol 5 mg IV), calcium channel blockers (diltiazem 0.25 mg/kg IV), or electrical cardioversion if the patient is hemodynamically unstable, as recommended by the European Heart Rhythm Association 1. Long-term management may include catheter ablation for recurrent episodes or maintenance medications to prevent recurrences. It's essential to consider the clinical history and physical examination to distinguish between different types of arrhythmias, as outlined in the ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias 1. In clinical practice, the management of SVT with aberrancy should prioritize the patient's hemodynamic stability and symptoms, with a focus on rapid and effective treatment to prevent complications and improve quality of life, as emphasized in the 2020 ESC guidelines for the management of patients with supraventricular tachycardia 1.

Some key points to consider in the management of SVT with aberrancy include:

• The importance of differentiating SVT with aberrancy from ventricular tachycardia to ensure proper treatment
• The use of medications such as adenosine, beta-blockers, and calcium channel blockers to treat SVT
• The role of electrical cardioversion in hemodynamically unstable patients
• The consideration of catheter ablation for recurrent episodes or maintenance medications to prevent recurrences
• The need for a thorough clinical history and physical examination to guide diagnosis and treatment.

Overall, the management of SVT with aberrancy requires a comprehensive approach that takes into account the patient's clinical presentation, ECG findings, and medical history, with a focus on providing effective and timely treatment to improve outcomes and quality of life.

From the Research

Definition of Supraventricular Tachycardia (SVT) with Aberrancy

• Supraventricular Tachycardia (SVT) is an abnormal rapid cardiac rhythm that involves atrial or atrioventricular node tissue from the His bundle or above 2
• SVT with aberrancy refers to a type of SVT where the supraventricular electrical impulse is conducted abnormally through the ventricular conducting system, resulting in a wide QRS complex 3, 4

Characteristics of SVT with Aberrancy

• SVT with aberrancy can be confused with ventricular tachycardia (VT) due to the wide QRS complex 3, 4
• The differential diagnosis of wide complex tachycardia includes SVT with aberrancy, VT, and antegrade SVT conduction over an accessory pathway (antidromic SVT) 3
• Electrocardiographic criteria, such as QRS duration and axis, morphology, and the presence of capture or fusion beats, can be useful in diagnosing wide complex tachycardia 3

Management of SVT with Aberrancy

• Hemodynamically unstable patients with a wide-complex tachycardia, including those with SVT with aberrancy, should be promptly cardioverted 4
• The management of SVT depends on the patient's clinical status, with vagal maneuvers and adenosine used for stable patients and synchronized cardioversion used for unstable patients 5