Best Evidence Topics
  • Send this BET as an Email
  • Make a Comment on this BET

Adenosine vs Verapamil in the acute treatment of supraventricular tachycardias

Three Part Question

In [adults with supraventricular tachycardia] is [adenosine or verapamil] more effective at [restoring sinus rhythm]?

Clinical Scenario

A 55 year old women presents to A & E with palpitations and shortness of breath. The physician on-call performs an ECG revealing a regular rhythm, with a p-wave distorting the start of the QRS complexes. The patient is diagnosed with atriventricular nodal re-entry tachycardia. Induction of AV block is attempted using both the carotid sinus massage and the valsava manoeuvre unsucessfully. The clinical team considers using either verapamil or adenosine as the next step in the managing this patient's arrhythmia.

Search Strategy

MedLine using the OVID interface-1966 to June Week 3 2005.
EMBASE using the OVID interface-1980 to 2005 Week 26
CINAHL using the OVID interface-1982 to June Week 3 2005
[(exp Supraventricular Tachycardia) OR (exp Tachycardia, Atrioventricular Nodal Reentry) OR (supraventricular OR (narrow complex tachycardia OR narrow-complex tachycardia OR junctional] AND [(exp Verapamil/) OR (] AND [(exp Adenosine) OR ( OR (] limit to (humans and english language)

Search Outcome

79 papers were found of which 4 were clinically relevant.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Garrat C. et al
20 patients with a history of documented, recurrent, sustained paroxysmal junctional tachycardia referred for electrophysiologic study. All drugs stopped >72 hours before admission, amiodarone stopped >3 monthsnon-randomized, unblinded crossover clinical trialsucessful termination of arrhythmia100% vs 95% (adenosine vs verapamil); p<0.05treatments were not randomly allocated small numbers criteria for exclusion not explained statistical methods not explained possibility for selection bias
presence of significant arrhythmias afterconversionocurred in 35% with verapamil vs 0% with adenosine; p<0.05
unmasking of latent or intermittent preexcitation0.5% revealed with verapamil vs 100% with adenosine; p<0.05
Rankin AC et al
february 1990
43 patients who presented with spontaneous episodes of paroxysmal tachycardia treated with either adenosine or verapamilretrospective reviewrestoring sinus rhythm (verapamil vs adenosine)81% vs 96% (p<0.05)treatments not randomly allocated outcomes not assessed blind sample size not justified patient bias
Di Marco JP et al
359 with a tachycardia electrocardiographically consistent with paroxysmal ventricular tachycardiatwo prospective,multicentre, double-blind, randomized, placebo controlled, single crossover clinical trialscumulative efficacy of adenosine vs placebo in conversion to sinus rhythm91.4% vs 16.1% (p<0.001)patient bias exclusion of patients to avoid verapamil side-effects randomisation not explained no confidence interval given
cumulative efficacy of adenosine vs verapamil in conversion to sinus rhythm93.4% vs 90.6% (p=NS)
Hood MA et al
New Zealand
25 patients with narrow complex tachycardia presenting to the emergency room and those whom tachycardia was induced in the electrophysiologic laboratoryRandomized, unblinded, double cross-over trialtermination of PSVT by adenosine vs verapamil100% vs 73%, p=0.07outcomes not assessed blind size of sample not justified no placebo control patient numbers small
conversion arrhythmias post administration of adenosine vs verapamil57% vs 50%, p=NS


Adenosine in doses up to 20 mg is a rapid, safe and effective means in terminating paroxysmal supraventricular tachycardias in patients whose arrhythmia did not responde to vagal manoeuvres. Side-effects are common but generally well tolerated and transient. It should be the treatment of choice in those patients in whom verapamil is known to have adverse effects, including those with hypotension, cardiac failure or who are taking beta-blocker drugs and in those in whom the diagnosis is in doubt (e.g. if the QRS complexes are broad). Verapamil is reserved in those in which adenosine produces severe symptoms, in those where arrhythmias recur or for patients with poor venous acess, patients with bronchospasm or those taking agents that interfere with adenosine action or metabolism like methylxanthines and dypiridamole.

Clinical Bottom Line

Adenosine is the initial drug in the acute management of paroxysmal supraventricular tachycardia after the failure of vagal manoeuvres.


  1. Garrat C. Linker N. Griffith M Ward D. Camm J. Comparison of Adenosine and Verapamil for termination of paroxysmal junctional Tachycardia The American Journal of Cardiology 1989;64:1310-1316
  2. Rankin AC. Rae AP Oldroyd KG Cobbe SM Verapamil or Adenosine for the Immediate Treatment of Supraventricular Tachycardia Quarterly Journal of Medicine February 1990; no 274,203-208
  3. Di Marco JP, Miles W, Akhtar M, Milstein S, Sharma A, Platia E, McGovern B, Sheinman M, Govier W Adenosine for Paroxysmal Supraventricular Tachycardia: Dose ranging and Comparison with Verapamil Annals of Internal Medicine 1990; 113:104-110
  4. Hood MA, Smith WM Adenosine versus Verapamil in the treatment of supraventricular tachycardia: a randomized control trial American Heart Journal 1992; 123: 1543