In 2004, the Interuniversity Cardiology Institute of the Netherlands (ICIN) took the initiative to develop a national registry for patients and families with familial heart diseases, named GENCOR (GENetic CORvitia). GENCOR aims to facilitate studies into the prevalence of familial heart diseases in the Netherlands and to promote research to improve the quality of diagnostics and therapy in familial heart diseases. 

GENCOR study population
Patients with primary cardiac arrhythmia syndromes (ion channelopathies) or secondary cardiac arrhythmia syndromes (cardiomyopathies) are potential candidates for the registry. Only when a mutation has been identified the patient is included in the registry. Patients with structural congenital heart defects (e.g. Tetralogy of Fallot, aortic coarctation, ventricular septal defect and atrial septal defects, aortic valvar stenosis) or Marfan syndrome are excluded from participation. 

ICIN’s working group on inherited cardiac diseases took the initiative to develop GENCOR. Cardiologists and clinical geneticists (with a special interest in cardiogenetics) of all the academic centres in the Netherlands are represented in this working group. GENCOR is directed by a project group and steering committee. The project group is responsible for the inclusion of patients, project documentation and public relations. The project group consists of two cardiologists (project managers), one research nurse (project coordinator), two clinical geneticists, an IT manager and a research fellow. The steering committee supervises the GENCOR project and consists of one representative from the Departments of Cardiology and/or Departments of Clinical Genetics per participating academic centre, the project managers and project coordinator. The representatives per centre can join the steering committee, depending on the contributions made to GENCOR. 

Inclusion procedure
Patients receive information about the aims and procedures of the GENCOR registry from their cardiologist / clinical geneticist during their visit to the outpatient clinic. Patients genotyped in the past receive the information at home. Patients are asked to sign a consent form and return it to the project coordinator before their data are stored in the GENCOR database. 

Data storage and protection
GENCOR is an internet-based registry. Patient data are entered into GENCOR by the cardiologist or clinical geneticist in attendance. In some cases trained research nurses enter the data. The patient data are collected from patient records from the departments of cardiology and clinical genetics. Each time a patient visits the outpatient clinic additional (new) data are added to the GENCOR registry. Each patient is allotted a unique GENCOR number. The patient data are stored in three layers. Layer 1 includes information about identification data of the patient, such as name, gender, date of birth and patient hospital number.
Layer 2 includes general information about patients examination status. It is noted whether the patient has had an electrocardiogram (ECG), echocardiography, 24-hour Holter monitor or other cardiac examinations. The results of the cardiac examinations, family history and DNA diagnostics are recorded in layer 3. Each layer is made up of one or more information blocks and each information block consists of variables with respect to the subject of the block. All collected data are stored in one central database. Users enter clinical data using a web application. Users need to log on using an individual username-password combination to which authorisations are connected. 

Data for research
GENCOR facilitates scientific research in two ways. Firstly, data stored in the GENCOR registry can be used for research projects. Secondly, specific data for a study can be collected using GENCOR. It is therefore possible to add information blocks to GENCOR to store additional information. In both cases the steering committee needs to approve the request before GENCOR data are delivered or provide the researcher a temporary account to collect the data needed and analyse it. 
For now four research projects have already started using GENCOR. One study aims to optimise the care of mutation carriers of HCM, identified by presymptomatic family screening, based on risk factors for sudden cardiac death. The second project is investigating an optimal strategy for ICD implantation in lamin A/C gene mutation carriers to prevent sudden cardiac death, which seems to be associated with mutations in this gene. For both projects the required patient data are entered into the GENCOR registry. The third project is investigating whether different HCM causing mutations are related to differences in the surface ECG, allowing a more efficiently targeted DNA analysis. The fourth research project evaluates functional and structural myocardial changes that can be observed in hypertrophic cardiomyopathy (HCM) mutation carriers who have not yet developed echocardiographic signs of hypertrophy by using cardiac magnetic resonance imaging (CMR). 

For more information about GENCOR please contact Dr. Wanda Hermans-van Ast (gencor@gencor.nl

Prof. Dr. F.W. Asselbergs, Durrer Center
Prof. Dr. P. van Tintelen, Durrer Center
Dr. J.F. Hermans-van Ast, project coordinator, Durrer Center 

Based on article of J.F. Hermans, I. Christiaans, J.P. van Tintelen, A.A.M. Wilde, Y.M. Pinto. GENCOR: a national registry for patients and families suffering from a familial heart disease in the Netherlands. Netherlands Heart Journal, Volume 14, Number 7/8, August 2006.