What is the management of Supraventricular Tachycardia (SVT) with palpitations?

From the Guidelines

SVT management should begin with vagal maneuvers, and if these fail, adenosine should be administered as the first-line medication, followed by other treatments such as calcium channel blockers or beta-blockers if necessary. The initial approach to managing supraventricular tachycardia (SVT) involves attempting to terminate the episode using vagal maneuvers like the Valsalva maneuver or carotid sinus massage, as these can be effective in up to 25% of cases 1.

Initial Management

If vagal maneuvers are unsuccessful, the next step is to administer adenosine, which is the preferred initial pharmacological treatment for terminating SVT episodes. The dosage of adenosine typically starts with a rapid IV bolus of 6 mg, followed by a 12 mg dose if needed, and another 12 mg dose if the arrhythmia persists.

Ongoing Management

For ongoing management of SVT, oral beta blockers, diltiazem, or verapamil are recommended for patients with symptomatic SVT who do not have ventricular pre-excitation during sinus rhythm 1. These medications can help reduce the frequency and duration of SVT episodes. Specifically, verapamil has been studied in randomized controlled trials (RCTs) and has shown reductions in SVT episode frequency and duration.

Long-term Prevention and Education

For long-term prevention, catheter ablation is a highly effective option, offering a definitive cure with success rates exceeding 95% for most SVT types 1. Additionally, patients should be educated on how to perform vagal maneuvers for ongoing management of SVT, as this can help terminate episodes and reduce the need for medical attention. Patients can be taught to perform a Valsalva maneuver or use other vagal maneuvers like applying an ice-cold, wet towel to the face.

Medication Options

Other medication options for ongoing management include flecainide or propafenone for patients without structural heart disease or ischemic heart disease who are not candidates for, or prefer not to undergo, catheter ablation. However, these medications carry a risk of proarrhythmia in certain patient groups and should be used with caution. Beta-blockers like metoprolol and calcium channel blockers like diltiazem are also effective for managing SVT symptoms.

Key Points

• Vagal maneuvers are the first line of treatment for SVT.
• Adenosine is the preferred initial pharmacological treatment.
• Oral beta blockers, diltiazem, or verapamil are recommended for ongoing management.
• Catheter ablation offers a definitive cure with high success rates.
• Patient education on vagal maneuvers and avoidance of triggers is crucial.

From the FDA Drug Label

For patients with PSVT and patients with PAF the recommended starting dose is 50 mg every 12 hours. Flecainide doses may be increased in increments of 50 mg bid every four days until efficacy is achieved For PAF patients, a substantial increase in efficacy without a substantial increase in discontinuations for adverse experiences may be achieved by increasing the flecainide dose from 50 mg to 100 mg bid. The maximum recommended dose for patients with paroxysmal supraventricular arrhythmias is 300 mg/day.

The management of Supraventricular Tachycardia (SVT) with flecainide involves:

• Starting with a dose of 50 mg every 12 hours
• Increasing the dose in increments of 50 mg bid every four days until efficacy is achieved
• The maximum recommended dose is 300 mg/day 2

From the Research

Diagnosis of Supraventricular Tachycardia (SVT)

• SVT refers to rapid rhythms that originate and are sustained in atrial or atrioventricular node tissue above the bundle of His 3
• The condition is caused by reentry phenomena or automaticity at or above the atrioventricular node, and includes atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and atrial tachycardia 3
• Diagnosis can be confirmed using a Holter monitor or event recorder, as physical examination and electrocardiography findings may be normal 3

Management of SVT

• Vagal maneuvers, such as the Valsalva maneuver, may terminate the arrhythmia 3, 4, 5
• Adenosine is effective in the acute setting if vagal maneuvers fail 3, 6
• Calcium channel blockers (diltiazem or verapamil) or beta blockers (metoprolol) can be used acutely or as long-term therapy 3
• Class Ic antiarrhythmics (flecainide or propafenone) can be used long-term, while Class Ia antiarrhythmics (quinidine, procainamide, or disopyramide) are used less often due to their modest effectiveness and adverse effects 3
• Catheter ablation has a success rate of 95% and recurrence rate of less than 5%, and is the preferred treatment for symptomatic patients with Wolff-Parkinson-White syndrome 3

Treatment Options

• The European Society of Cardiology guidelines advocate the use of vagal maneuvers and adenosine as first-line therapies in the acute diagnosis and management of SVT 6
• Alternative therapies include the use of beta-blockers and calcium channel blockers 6
• Long-term treatment is dependent on several factors, including frequency of symptoms, risk stratification, and patient preference 6
• Management can range from conservative to catheter ablation, which is curative in the majority of patients 6