Despite advancements in prevention and treatment, sudden cardiac death (SCD) remains a leading cause of mortality and is responsible for approximately half of all deaths from cardiovascular disease worldwide. Now, a team of researchers from Tampere University in Finland have found a new method for identifying cardiac rhythms associated with imminent heart failure.
According to a report by Science Alert, the new algorithm makes use of a particular metric called detrended fluctuation analysis (DFA2 a1), which can detect changes in heart rate variability over time.
In a study tracking 2,794 adults over approximately 8.3 years, researchers determined that DFA2 a1 serves as a robust predictor of SCD. This association proved most pronounced during periods of rest, contrasting with its impact during physical exertion.
"The most interesting finding of the study is the identification of differences specifically during measurements at rest. The characteristics of heart rate intervals of high-risk patients at rest resemble those of a healthy heart during physical exertion,'' Tampere University physicist Teemu Pukkila explained.
The team employed statistical analysis methods to establish a link between DFA a1 patterns and occurrences of SCD. Their approach involved accounting for the influence of crucial variables such as age and pre-existing heart conditions.
Significantly, the metric can be assessed in just a minute, using sensors small and uncomplicated enough to be integrated into a smartwatch. This development eliminates the need for clinic visits or complex scans to evaluate an individual's risk of SCD.
"Accelerometers in wearable consumer devices can easily distinguish between the states of physical activity and rest and perform the measurement when applicable," researchers wrote in their paper.
The new predictive algorithm is said to be more accurate than current methods, which usually focus on assessing cardiorespiratory fitness.
What is Sudden Cardiac Arrest?
'Sudden Cardiac Arrest' (SCA) as the name suggests - is where a patient is stable with a stable heart function an hour before the terminal event (namely Cardiac Arrest). The sudden stoppage of the heartbeat is due to disruption in the rate and rhythm of the electrical system of the heart, impairing the heart's ability to pump blood, which causes them to lose consciousness and their ability to breathe.
SCD, or sudden cardiac death, differs from heart attacks in its cause: while heart attacks stem from restricted blood flow to the heart, SCD results from the heart being overwhelmed by abrupt electrical impulses. It can also occur in a young and outwardly healthy person, for example, in connection with strenuous sports.
