Prevalence of Congenital Long QT Syndrome and Acquired QT Prolongation in a Hospital Cohort

NCT03544918 | Completed

• 1 other identifier: REK 2013/1090
• Study Type: observational
• Target: 1,536
• Locations: 1 country
• Sites: 1

Brief Summary

The Long QT syndrome is associated with potentially life-threatening cardiac arrhythmias as ventricular tachycardia (Torsade de pointes) as well as ventricular fibrillation, and might lead to syncope as well as sudden cardiac death (1). Good results have been achieved by treating patient at risk with beta blockers and implantable cardiac defibrillator (ICD). It is therefore important to diagnose the condition as early as possible as the disease is treatable (2). Prolonged QT duration might also be induced by the intake of numerous pharmaceutical substances, as well as with electrolyte disturbances, which also increases the risk of life-threatening cardiac arrhythmias. Furthermore, congenital LQTS can arise from mutations in one of at least 13 different genes. Many of these genes encode proteins which are constituents of ion channels. The genetically defined long QT syndrome has autosomal dominant (Romano Ward Syndrome) or autosomal recessive (Jervell and Lange-Nielsen Syndrome) inheritance. In this study we are using the hospital ECG database obtained with the GE Marquette 12SL ECG Analysis Program® at Telemark Hospital Skien recorded between March 2004 and April 2014. This database stores approximately 200 000 ECG recordings from 60 000 unique patients. By using the search algorithm in the MUSE ECG database, 2398 recordings have been be identified from 1603 patients where the corrected QT time is longer than 500 ms, and QRS is less than 120 ms. ECG recordings with QT intervals longer than 500 ms represents less than 1% of the population (5). Individuals having these recordings are selected for extensive clinical follow up. The patients will be offered the opportunity to have genetic analysis performed in order to distinguish between inherited or acquired long QT syndrome. The appropriate treatment will be initiated according to guidelines for patients with inherited QT syndrome. For patients with aquired long QT syndrome substitution of unfavourable pharmacotherapy or correction of electrolytes shall be performed in order to reduce their risk of cardiac arrhythmias. A T wave morphology score gives independent prognostic information useful for risk stratification. The purpose of this substudy is to examine if the T wave morphology score applied on the 1531 patients ECGs with QTc \>500 ms, has independent prognostic value in this cohort.

Conditions

Long QT Syndrome

Outcome Measures

Primary Outcomes (1)

• survival

  Death certificate information from national register

  2004-2014

Secondary Outcomes (1)

• comorbidity data from hospital database Genetic defects data

  2004-2014

Study Arms (2)

Patients with long QT syndrome.

Patents with Long QT syndrome hospitilized. To be followed over time with no intervention. Observational study.

Patients in Telemark with normal QT time

Patients in Telemark with normal QT time. To be followed over time with no intervention. Observational study.

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The Long QT syndrome is associated with potentially life-threatening cardiac arrhythmias. In this study we are using the hospital ECG database obtained with the GE Marquette 12SL ECG Analysis Program® This database stores approximately 200 000 ECG recordings from 60 000 unique patients. By using the search algorithm in the MUSE ECG database, 2398 recordings have been be identified from 1603 patients where the corrected QT time is longer than 500 ms, and QRS is less than 120 ms.

You may qualify if:

• QT time in EKG more Tham 500 ms -

You may not qualify if:

• Patient refuses to be a part of the study registry

Sponsors & Collaborators

• Sykehuset Telemark: lead
• Oslo University Hospital: collaborator

Study Sites (1)

Sykehuset Telemark

Skien, Telemark, NO-3710, Norway

Location

Biospecimen

Retention: SAMPLES WITH DNA

Blood samples for DNA Analysis. Parafin embeded tissue will be used as well

MeSH Terms

Conditions

Long QT Syndrome

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Cardiac Conduction System Disease; Heart Defects, Congenital; Cardiovascular Abnormalities; Congenital Abnormalities; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Jan Hysing, PhD

  Sykehuset Telemark

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Target Duration: 10 Years
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD PhD cardiologist consultant

Study Record Dates

• First Submitted: May 22, 2018
• First Posted: June 4, 2018
• Study Start: June 1, 2015
• Primary Completion: November 6, 2020
• Study Completion: November 6, 2020
• Last Updated: November 9, 2020

Record last verified: 2020-11

Locations

NO (1)