Adenosine induced PR jump on surface ECG to differentiate atrioventricular nodal re-entrant tachycardia from concealed accessory pathway mediated tachycardia: a bedside test

Abstract

Objective: To evaluate the efficacy of single dose intravenous adenosine in differentiating atrioventricular nodal re-entrant tachycardia (AVNRT) from concealed pathway mediated atrioventricular re-entrant tachycardia (AVRT) using surface ECG at the bedside. Method: 12 mg of adenosine was administered to 97 consecutive patients who had documented narrow QRS tachycardia without manifest pre-excitation. The test was labelled positive for AVNRT if surface ECG recordings showed signs of dual atrioventricular (AV) node physiology-namely, PR jump or AV nodal echo. The diagnostic value of this test was evaluated by electrophysiological study as the yardstick.Results: The adenosine test was positive for AVNRT in 48 patients (adenosine induced PR jump in 48, AV nodal echo in 3) and negative in 49 patients. On electrophysiological study, 62 patients had AVNRT and 35 had concealed pathway mediated AVRT. Thus, the test had a sensitivity of 74% and specificity of 94%. The positive predictive value was 96% and the negative predictive value was 67%. Conclusion: Single dose (12 mg) intravenous adenosine administered during sinus rhythm can identify dual AV node physiology on surface ECG recording at the bedside. A positive adenosine test identified by a PR jump can differentiate AVNRT from AVRT with a high specificity and positive predictive accuracy.

Coronary sinus diameter by echocardiography to differentiate atrioventricular nodal reentrant tachycardia from atrioventricular reentrant tachycardia

“…Adenosine administration can unmask pathway conduction in patients with latent preexcitation and demonstrate dual AV nodal conduction in some patients with AVNRT [4] with a sensitivity of 74%, but is cumbersome to perform.…”

“…History of neck pulsation, age at onset of symptoms and female sex have been shown to indicate the diagnosis of AVNRT [1][2][3]. Administration of adenosine or adenosine tri-phosphate has also been used to unmask accessory pathway conduction or dual atrioventricular nodal physiology [4][5][6]. Studies using venography have shown that the coronary sinus (CS) is larger and has a wind--sock shape in patients with AVNRT compared to controls [7,8].…”

Limited Dose-Effect Relationship of Adenosine for Detection of Atrioventricular Nodal Duality in Patients with Supraventricular Tachycardias

“…Side effects, such as sinus pauses and bradycardia following termination of the arrhythmia, were directly correlated with the dose employed. Other investigators focused their interest on the pharmacological effects of the very short-acting drug adenosine [7,8,13] . Burkart et al [13] used a mean dose of 7.1 8 3.9 mg adenosine to block the AV node while pacing the atrium.…”

“…Only those patients who demonstrated neither a significant PR jump nor a high-grade AV block after injection of 12 mg adenosine received an 18-mg bolus of adenosine intravenously after a waiting period of another 5 min. Furthermore, the occurrence of AV nodal echo beats or AV reentrant echo beats was evaluated based on the definition of previous studies [4,5,8] . The results were reviewed and graded by two independent electrophysiologists.…”

“…Previous studies demonstrated that administration of adenosine triphosphate or adenosine during sinus rhythm helps to identify the mechanism of supraventricular tachycardia (SVT) in patients presenting with palpitations [3][4][5][6][7][8][9] . Moreover, both short-acting drugs have been used to differentiate AVNRT from AV reentrant tachycardia (AVRT) [5,8] . The use of this simple noninvasive test may help select patients for early referral to invasive electrophysiological (EP) evaluation.…”