From the Guidelines
The emergency treatment for supraventricular tachycardia (SVT) begins with vagal maneuvers such as the Valsalva maneuver or carotid sinus massage, which can terminate the arrhythmia by increasing parasympathetic tone. If these fail, intravenous adenosine is the first-line pharmacological treatment, typically administered as a rapid bolus of 6 mg, followed by a 12 mg dose if needed, with a possible third dose of 12 mg if the arrhythmia persists, as recommended by the 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia 1. Adenosine works by temporarily blocking AV node conduction, interrupting the reentry circuit responsible for SVT. For patients with contraindications to adenosine (such as asthma or severe hypotension), calcium channel blockers like verapamil (5-10 mg IV) or diltiazem (0.25 mg/kg IV) can be used, as suggested by the guideline 1. Beta-blockers such as metoprolol (5 mg IV) are also effective alternatives. In hemodynamically unstable patients presenting with hypotension, altered mental status, or chest pain, immediate synchronized electrical cardioversion at 50-100 joules is indicated, as recommended by the guideline 1. After acute management, patients should be evaluated for underlying causes and may require long-term antiarrhythmic therapy or catheter ablation to prevent recurrence.
Some key points to consider in the management of SVT include:
- Vagal maneuvers are recommended as the first-line treatment for SVT, with a success rate of 27.7% 1.
- Adenosine is effective in terminating SVT in approximately 95% of patients, with minor and brief side effects occurring in approximately 30% of patients 1.
- Synchronized cardioversion is highly effective in terminating SVT, and should be performed in hemodynamically unstable patients or in patients who do not respond to pharmacological therapy 1.
- Calcium channel blockers and beta-blockers can be used as alternative treatments for SVT, but should be used with caution in certain patient populations, such as those with suspected systolic heart failure or asthma 1.
Overall, the management of SVT requires a step-wise approach, starting with vagal maneuvers and progressing to pharmacological therapy and cardioversion as needed, with consideration of the patient's underlying medical conditions and potential contraindications to certain treatments.
From the FDA Drug Label
1 INDICATIONS & USAGE 1. 1 Supraventricular Tachycardia or Noncompensatory Sinus Tachycardia Esmolol hydrochloride injection is indicated for the rapid control of ventricular rate in patients with atrial fibrillation or atrial flutter in perioperative, postoperative, or other emergent circumstances where short-term control of ventricular rate with a short-acting agent is desirable
14 CLINICAL STUDIES Supraventricular Tachycardia In two multicenter, randomized, double-blind, controlled comparisons of esmolol hydrochloride with placebo and propranolol, maintenance doses of 50 to 300 mcg/kg/min of esmolol hydrochloride were found to be more effective than placebo and about as effective as propranolol, 3 to 6 mg given by bolus injections, in the treatment of supraventricular tachycardia, principally atrial fibrillation and atrial flutter.
The emergency treatment for supraventricular (SV) tachycardia is esmolol hydrochloride injection at a dosage of 50 to 300 mcg/kg/min, with an average effective dosage of approximately 100 mcg/kg/min 22.
- Key points:
- Esmolol hydrochloride is indicated for the rapid control of ventricular rate in patients with atrial fibrillation or atrial flutter.
- The treatment is intended for short-term use in perioperative, postoperative, or other emergent circumstances.
- Significant decreases of blood pressure occurred in 20 to 50% of patients, and hypotension was more common with esmolol hydrochloride than with propranolol.
From the Research
Emergency Treatment for Supraventricular Tachycardia
The emergency treatment for supraventricular (SV) tachycardia can be categorized into several forms, including:
- Nonpharmacologic treatments that increase vagal tone, such as the Valsalva maneuver, carotid sinus massage, and other vagal maneuvers 3, 4, 5, 6
- Pharmacologic treatments, including verapamil, digitalis, and adenosine 3, 7
- Electrical treatments, such as synchronized electrical countershock for hemodynamically unstable patients 3, 7
Treatment Approaches
The approach to treatment depends on the patient's clinical status:
- For hemodynamically stable patients, vagal maneuvers and pharmacologic agents such as verapamil and adenosine can be used 3, 4, 7
- For hemodynamically unstable patients, synchronized electrical countershock is the treatment of choice 3, 7
- Modified Valsalva maneuvers have also been described as a potential treatment option, with reported success rates higher than traditional Valsalva maneuvers 4, 6
Specific Patient Populations
In certain patient populations, such as those with Wolff-Parkinson-White syndrome, specific treatment approaches may be recommended: