Comparison Between Epinephrine and Exercise Test in QT Long Syndrome Patients

Study Overview
=================
Brief Summary
-----------------
The aim of the study is to evaluate the best stress exam to unmask long QT in patient with KCNQ1 or KCNH2 mutation without long QT interval in rest electrocardiogram.

Detailed Description
-----------------
65 patients with KCNQ1 or KCNH2 mutation presenting QTc interval <470msec and 65 patients without KCNQ1 or KCNH2 mutation presenting QTc interval <470msec will be included. All patients will have the 2 tests: exercise test and epinephrine test, in one half day. At the end of the inclusions, two experts will examine examens results without knowing in which arm (mutated or not) the patient belongs.

Official Title
-----------------
Comparison Between Epinephrine and Exercise Test in QT Long Syndrome Patients With KCNQ1 or KCNH2 Mutation Without Long QT Interval in Rest ECG

Conditions
-----------------
Long QT Syndrome Type 1 or 2

Intervention / Treatment
-----------------
* Other: exercise test
* Other: Epinephrine test


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients with QTc<470 msec, and with molecular analysis (KCNQ1 or KCNH2 genes) performed in order to include 65 patients with KCNQ1 or KCNH2 mutation and 65 patients without KCNQ1 or KCNH2 mutation (controls). Exclusion Criteria: QTc interval >470msec Treatment interfering with cardiac repolarisation Under 15 years old Pregnant women Contraindication to exercise or epinephrine tests Patients without social coverage

Ages Eligible for Study
-----------------
Minimum Age: 15 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: patients with KCNQ1 or KCNH2 mutation<br> | Other: exercise test<br>* Exercise test : Bruce protocol : exercise during 7 minutes, and rest during 6 minutes with registering of the electrocardiograms.<br>Other: Epinephrine test<br>* Epinephrine test : 1 hour after exercise test : epinephrine infusion during 20 minutes, and monitoring during 30 minutes after stop infusion with registering of electrocardiograms.<br>|
| Other: patients WITHOUT KCNQ1 or KCNH2 mutation (control group)<br> | Other: exercise test<br>* Exercise test : Bruce protocol : exercise during 7 minutes, and rest during 6 minutes with registering of the electrocardiograms.<br>Other: Epinephrine test<br>* Epinephrine test : 1 hour after exercise test : epinephrine infusion during 20 minutes, and monitoring during 30 minutes after stop infusion with registering of electrocardiograms.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| to evaluate the best stress exam (exercise test OR epinephrine test)to unmask long QT syndrome. | Exercise test and epinephrine test will be done at inclusion (day 1). The primary outcome of this study is to evaluate the best stress exam (exercise test versus epinephrine test), defined by a positive test to unmask long QT syndrome. Test is positive when QT interval lengthens 30 ms At the end of study inclusions, two reviewers will analyse, independently, electrocardiograms resulting from these tests to determine for each patient if a test was positive and which one. These reviewers will do this job without being informed of the patient status (mutated patient or not mutated patient (control)). | day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| to evaluate each test characteristics | Exercise test and epinephrine test will be done at inclusion (day 1). The secondary outcome is to evaluate each test (exercise test and epinephrine test) characteristics. At the end of study inclusions, two reviewers will independently analyse electrocardiograms resulting from these tests to evaluate their characteristics. | Day 1 | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Long QT syndrome, stress tests