Low-dose Epinephrine Infusion Tests in Adolescent and Pediatric Patients

Summary

Long QT syndrome (LQTS)is a cardiac disorder that may lead to ventricular arrythmias and culminate in syncope and/or possible death.

Recently, researchers have developed a way of discovering patients with LQTS by using low doses of epinephrine by a continuous, intravenous infusion in adults. Epinephrine, or adrenaline, is produced by our bodies in times of stress. By producing adrenaline, your body allows itself to adapt to its stressful environment and take appropriate actions (i.e. fight or flight response). By simulating this response with very small amounts of epinephrine, researchers have shown prolongation of the QT interval does not occur in normal healthy adults. However, adults with confirmed LQTS Type 1 (LQTS-1) will prolong their QT interval when given low dose epinephrine. Therefore, this test can act as a safe means of identifying adults with LQTS-1 who do not have prolonged QT intervals on their resting EKGs.

However, LQTS is not just a disease of adults, it affects children as well. Currently the standard of care is to obtain resting EKGs on our pediatric patients which can miss those patients with concealed LQTS. Those patients, who are old enough, can undergo exercise testing. Yet this leaves young children unable to run on a treadmill without a diagnostic test.

Hypothesis: The low-dose epinephrine infusion stress test does not cause prolongation of the QT interval in an electrophysiologically normal healthy pediatric population.

Conditions

• Congenital Disorders

Interventions

DRUG

Epinephrine

We will follow the protocol outlined by Ackerman et al. known as the Mayo protocol4 which is currently used routinely in our electrophysiology laboratory. Epinephrine infusion will begin at 0.025 ug/kg/minute, for ten minutes and a twelve-lead electrocardiogram is obtained at time=0 minutes, 5 minutes, and 10 minutes. The epinephrine infusion will then be increased to 0.05 ug/kg/minute for five minutes and the electrocardiogram repeated. The epinephrine infusion will then be increased to a maximal dose of 0.1 ug/kg/minute for five minutes and electrocardiogram obtained. The epinephrine infusion is then discontinued and measurements are obtained at five minutes and ten minutes after stopping the epinephrine infusion. The total time of procedure will be 35 minutes.

Sponsors & Collaborators

• Children's Healthcare of Atlanta

  collaborator OTHER

• Emory University

  lead OTHER

Principal Investigators

• Peter Fischbach, MD, MA · Emory University

Study Design

Allocation

NA

Purpose

HEALTH_SERVICES_RESEARCH

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

3 Years

Max Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2008-02-29

Primary Completion

2012-01-31

Completion

2012-06-30

Countries

• United States

Study Locations