Evaluating Familial Screening After a Hypertrophic Cardiomyopathy-Related Sudden Cardiac Death
Introduction to project
This project aims to evaluate the screening process in the first-degree relatives of people with hypertrophic cardiomyopathy (HCM) who have died suddenly.
What is the condition?
Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac condition, affecting about 1 in 500 people in the UK. HCM is characterised by unexplained thickening of the heart muscle. Although many people with the condition can be asymptomatic and live normal lives, many develop complications such as arrhythmia, stroke, heart failure and sudden cardiac death.
When someone is found to have HCM, for example, after a sudden cardiac death, the first-degree family members of those affected are offered screening. The aim is to reduce morbidity and mortality amongst affected relatives. Management options include implantable cardioverter-defibrillators for those at high risk of sudden death.
Where the affected person carries a faulty gene, screening starts with genetic testing. For those found to carry the faulty gene, a heart tracing and scan (electrocardiogram and echocardiogram) are then performed to look for evidence of the condition. Heart tracings and scans alone are used in families without the faulty gene or where testing is absent.
Since the condition can be latent, re-screening with these tests occurs periodically through childhood and adulthood.
What are we doing?
The British Heart Foundation is working with the National Coronial Service to improve access to genomic testing for families after a sudden cardiac death. A new pathway is being tested across several pilot sites, including Birmingham.
Our project dovetails with this pilot by focusing on historic screening activity at our hospital following a sudden cardiac due to HCM. We hope to provide useful insights for the team implementing the pathway locally by studying how well screening has been performed in the past.
This work is hampered by the fact that hospitals do not routinely collect a list of tested family members. The alternative is that teams need to scour records looking for relatives, but this takes time.
Working with collaborators from the University of Birmingham, we have extended our existing text–mining tool to automatically search clinical documents for specific words used in select contexts.
We will evaluate the tool’s accuracy and will then text-mine our entire electronic record. We will check the results against other data sources and do a manual review before finalising the relative list. Each relative record will then be evaluated to compare what happened in practice with the screening standards set out in international guidelines.