Dexmedetomidine and Adenosine: Therapeutic Use for SVT

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the efficacy and safety of dexmedetomidine in the acute termination of Supraventricular Tachycardia (SVT).

Detailed Description
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In 2006 the investigator found that dexmedetomidine, an alpha-2 adrenergic agonist with primarily sedative properties, possesses additional anti-arrhythmic properties. So far the investigator has found that dexmedetomidine has the ability to prevent or terminate arrhythmias like atrial ectopic tachycardia (85% success) and junctional ectopic tachycardia (75% success). The most dramatic effect however was observed in the acute termination of reentrant SVT with a success rate of > 96%. More importantly we found that dexmedetomidine terminates SVT without causing any sinus pause or asystole (frequently seen with adenosine) and thus avoiding the feeling of impending doom. In this study adenosine is being compared head to head with dexmedetomidine in a cross over study, for both safety and efficacy when given for the termination of SVT in the electrophysiology (EP) lab. Additional EP parameters will be measured to elucidate the exact site of dexmedetomidine's mechanism of action.

Official Title
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Dexmedetomidine Versus Adenosine: Electrophysiologic Effects and Therapeutic Use for Terminating Supraventricular Tachycardia

Conditions
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Supraventricular Tachycardia

Intervention / Treatment
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* Drug: Dexmedetomidine
* Drug: Adenosine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients between the age of 5 - 30 years old, who are scheduled for cardiac electrophysiology study for evaluation of reentrant SVT Exclusion Criteria: Severe Heart Failure Presence of of any other antiarrhythmic medication within 24 hours of enrollment Third degree heart block Sick Sinus Syndrome

Ages Eligible for Study
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Minimum Age: 5 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Adenosine and Dexmedetomidine<br>Patients will receive adenosine and then dexmedetomidine for the termination of SVT | Drug: Dexmedetomidine<br>* Dexmedetomidine 2 mcg/kg, Intravenous push<br>* Other names: Precedex;Drug: Adenosine<br>* Stepwise incremental approach of adenosine starting at 0.2 mg/kg (max 6 mg) followed by 0.3 mg/kg (max 12 mg) if initial dose was unsuccessful<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Termination of SVT | Number of participants with SVT Termination within 3 minutes of medication administration | Within 3 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Sinus Pause >2.5 Sec After Termination of SVT | Evaluation of the number of participants with sinus pause > 2.5 sec, after dexmedetomidine vs. adenosine induced SVT termination | 1 minute | 
| Number of Participants With Tachyarrhythmias After Medication Administration | Number of participants with tachyarrhythmias, including Ventricular (Ventricular Tachycardia & Fibrillation)and supraventricular (Atrial Flutter & Fibrillation) after dexmedetomidine vs. adenosine administration | 10 minutes | 
| Number of Participants With Hypotension by Non-invasive Cuff in First 10 Minutes After Medication Administration | Blood pressure changes after dexmedetomidine vs. adenosine. Blood pressure measured by non-invasive cuff prior to medication administration, and then at 1 min, 3 min, 5 min after medication administration. Number of participants with a significant drop in blood pressure (mmHg) compared to baseline would be counted for hypotension. | 10 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Supraventricular Tachycardia, SVT, Reentrant Tachycardia, Dexmedetomidine, Adenosine