(Ivanhoe Newswire) – A two-in-one test may help save
the lives of heart attack patients.
New research from the University of Calgary, Canada shows two results from one
simple test makes it much more likely for doctors to identify patients who have
the greatest risk of cardiac arrest or death, even years after they have a heart
attack. The test lets doctors look at both the nervous system and the heart’s
electrical system.
The REFINE study (Risk Estimation Following Infarction, Noninvasive Evaluation)
examined two critical factors that can cause serious cardiac arrhythmias. An
electrical system damaged by a heart attack can lead to serious disturbances in
the heart’s rhythm; and a nervous system on high alert makes a patient more
likely to have a serious arrhythmia that will progress to cardiac arrest and
death.
322 patients who had a heart attack and had at least a mild abnormality in the
heart’s pumping ability took part in the study. Participants wore a heart
monitor for 18 to 24 hours a day. Researchers looked for abnormalities in the
heart’s rhythm called T-wave alternans (TWA) and checked to see if the nervous
system was on high alert by looking for abnormalities in heart rate turbulence (HRT)
– a measure of the heart’s ability to adapt to change.
Results shows the 20-percent of patients who had both TWA and impaired HRT on
the heart monitor as well as a persistent abnormality in the heart’s pumping
ability had more than six times the risk of cardiac arrest or death compared to
other participants.
Studies are expected to begin in 2008 to look at whether an implantable
defibrillator can save the lives of patients with abnormalities in both the
nervous system and the heart’s electrical system.
SOURCE: Journal of the American College of Cardiology, 2007;
