NCT04328376

Measurement of the Electromechanical Window to Improve the Diagnosis of Congenital Long QT Syndrome

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 224 (actual)
• Sponsor: University Hospital, Bordeaux · Academic / Other
• Sex: All
• Age: 12 Years
• Healthy volunteers: Not accepted

Summary

The goal of this research is to prospectively evaluate the performance of the electromechanical window according to a phonographic method, as a mean of diagnosis of long QT syndrome, and to compare its performance with routine tests used.

Detailed description

Familial long QT syndrome (LQTS) is a hereditary cardiac disorder in which most affected family members have delayed ventricular repolarization manifest on the electrocardiogram (ECG) as QT prolongation. This disease is associated with an increased propensity to palpitations, syncope, polymorphous ventricular tachycardia and sudden arrhythmic death. The diagnosis relies mostly on resting ECG findings and on genetic testing. In clinical practice however, this diagnosis is complicated by 2 main reasons: 1) a significant overlap in ECG findings between healthy and diseased individuals and 2) a frequent identification of genetic variants of unknown significance. Recent studies have suggested that echocardiographic measurement of the electromechanical window (EMW - the delay between the end of mechanical contraction and electrical activation of the heart) has better performance in the diagnosis of LQTS. The echocardiographic technique is however too complicated for routine clinical use. Preliminary work conducted at the University Hospital of Bordeaux and at the University Hospital of Reunion Island has demonstrated that a phonocardiographic approach leads to similar results with an improved feasibility and a good reproducibility.

Conditions

• Long QT Syndrome

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	ECG coupled to phonocardiography	A standard ECG is recorded along with a phonocardiographic recording. The phonocardiographic recording is obtained by using a specific electronic stethoscope plugged into the auxiliary port of the ECG machine. The recording takes less than 30 seconds. The two recording methods are concomitant. QT interval is measured on the ECG recording, EMW is measured with ECG coupled to phonocardiography.

Timeline

• Start date: 2020-08-28
• Primary completion: 2024-04-23
• Completion: 2024-04-23
• First posted: 2020-03-31
• Last updated: 2025-06-17

Locations

4 sites across 1 country: France