Adenosine versus intravenous calcium channel antagonists for supraventricular tachycardia
S.C. Medicina e Chirurgia d’Accettazione e Urgenza,A.O. “Ordine Mauriziano”, Torino
What we already know about this topic
Paroxysmal supraventricular tachycardia (PSVT) is a rather common arrhythmia in the Emergency Department, with an incidence of 35 cases per 100,000 person-years (1). Patients usually complain sudden onset of palpitations, anxiety, light-headedness and neck-pounding. 12-lead electrocardiogram shows a regular tachycardia with narrow QRS-complexes and heart rate > 110 bpm.
Even if often presented as the first choice for arrhythmia termination, vagal maneuvers are poorly effective, with a success rate of about 20% (2). If PSVT does not respond to vagal maneuvers, ACLS Guidelines recommend giving 6 mg of adenosine as a rapid IV push (3). Similar indications can be found in the “2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia” (4).
Nonetheless, non-dihydropyridine calcium channel blockers (CCB) (verapamil and diltiazem), even if considered second line agents by these documents, showed high efficacy in the past (5), constituting a reasonable alternative to adenosine. To further clarify the clinical efficacy of these drugs in respect to the latter, Alabed et al. conducted a systematic review (6).
The Cochrane review (6)
- reversion to sinus rhythm,
- major adverse events (defined as cardiac arrest, prolonged hypotension, symptomatic bradycardia requiring treatment, and acute cardiac failure).
- time to reversion to sinus rhythm,
- rate of relapse to PSVT within two hours after reversion, length of stay in hospital, minor adverse events, patient satisfaction as measured on any validated scale.
Table 1.Results of the systematic review. Conclusions may be drawn only for main outcome.
Comment and conclusions
- Adenosine: 6 mg of IV as a rapid IV push through a large (eg, antecubital) vein followed by a 20 mL saline flush. If the rhythm does not convert within 1 to 2 minutes, give a 12 mg rapid IV push using the method above.
- Verapamil, give a 2.5 mg to 5 mg IV bolus over 2 minutes (over 3 minutes in older patients). If there is no therapeutic response and no drug-induced adverse event, repeated doses of 5 mg to 10 mg may be administered every 15 to 30 minutes to a total dose of 20 mg.
- Diltiazem, give a dose of 15 mg to 20 mg (0.25 mg/kg) IV over 2 minutes; if needed, in 15 minutes give an additional IV dose of 20 mg to 25 mg (0.35 mg/kg). The maintenance infusion dose is 5 mg/hour to 15 mg/hour, titrated to heart rate.
- Orejarena LA, Vidaillet H Jr, DeStefano F, Nordstrom DL, Vierkant RA, Smith PN, Hayes JJ. Paroxysmal supraventricular tachycardia in the general population. J Am Coll Cardiol. 1998 Jan;31(1):150-7.
- Smith GD, Fry MM, Taylor D, Morgans A, Cantwell K. Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia. Cochrane Database Syst Rev. 2015 Feb 18;(2):CD009502.
- Part 7: Adult Advanced Cardiovascular Life Support. Web-based Integrated 2010 & 2015 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care.
- Page RL, Joglar JA, Caldwell MA, Calkins H, Conti JB, Deal BJ, Estes NAM 3rd, Field ME, Goldberger ZD, Hammill SC, Indik JH, Lindsay BD, Olshansky B, Russo AM, Shen WK, Tracy CM, Al-Khatib SM. 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2016 Apr 5;67(13):e27-e115.
- Delaney B, Loy J, Kelly AM. The relative efficacy of adenosine versus verapamil for the treatment of stable paroxysmal supraventricular tachycardia in adults: a meta-analysis. Eur J Emerg Med. 2011 Jun;18(3):148-52.
- Alabed S, Sabouni A, Providencia R, Atallah E, Qintar M, Chico TJA. Adenosine versus intravenous calcium channel antagonists for supraventricular tachycardia. Cochrane Database Syst Rev 2017; 10: CD005154.