Novel Applications for Measuring T Wave Alternans
Research type
Research Study
Full title
A Pilot Study Investigating the Clinical Application of Measuring T Wave Alternans in Patients with either Atrial Fibrillation, a Pacemaker or Heart Failure
IRAS ID
120920
Contact name
Alexander Lyon
Contact email
Research summary
T wave alternans (TWA) is a measure of the electrical instability of the heart and has been shown to predict which people are more likely to experience life threatening heart rhythm disorders. Identification of high risk patients is critical because implantation of a defibrillator may be lifesaving. Two important groups of people have generally been excluded from research in this area: those who have pacemakers and those with an irregular heart rhythm known as atrial fibrillation (AF). In addition, the more recent method of measuring TWA called the modified moving average method has not been fully utilised in patients with heart failure.
We plan to assess whether it is possible to reliably measure TWA in these 3 groups of patients using 48 hour Holter monitors. These are small devices, the size of a mobile phone, with wires which connect to the skin through electrode stickers. They are worn for 48 hours while the subject carries on normal activities and the information then downloaded to a computer for analysis.
Once feasibility is proven we will go on to perform exploratory research to investigate the effect AF or pacing has on TWA. We will recruit patients in AF who are due to have an electrical cardioversion which will restore normal heart rhythm, “sinus rhythm”. We can then compare TWA in AF with normal sinus rhythm. To assess the effect of pacemakers on TWA we will identify patients who are due to have a pacemaker implanted and take measurements before and after the pacemaker is implanted. Finally, we will compare TWA in patients with mild heart failure, severe heart failure and those with heart failure but preserved ejection fraction.
This research is of particular importance to help develop a non-invasive tool which can aid identification of patients who would benefit from defibrillator implantation.REC name
South Central - Oxford B Research Ethics Committee
REC reference
13/SC/0294
Date of REC Opinion
12 Jul 2013
REC opinion
Further Information Favourable Opinion