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Artificial Intelligence in Health Opportunities for AI-based arrhythmia screening

more, the condition is diagnosed as sinus arrhythmia.
This condition is common across all age groups but is
particularly prevalent in teenagers and pre-teens, where it
is sometimes not considered a pathological condition. One
potential cause of sinus arrhythmia is the influence of the
vagus nerve, which regulates both respiration and heart
rhythm. Through the effects of the vagus nerve on the
sinus node, the heart rate is increased during inspiration
and decreased during expiration.

Accurate detection of fetal cardiac signals during
pregnancy is critical for identifying potential congenital
heart conditions. Fetal ECG recordings are obtained using
leads placed in a special arrangement on the abdomen of
the mother. While the maternal ECG is dominant, the
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fetal ECG, which is superimposed on the maternal ECG,
can be isolated using frequency-domain filtering. The
fetal heart rate is generally higher than the maternal heart
rate, enabling effective separation of the two signals using
filters designed and configured in the frequency domain.
Advanced frequency and wavelet analysis techniques are
essential for extracting meaningful diagnostic information
from these recordings.
ECG signals are stochastic and rarely perfectly
Figure 7. Representation of several characteristic electrocardiogram reproducible. Direct analytical methods based solely on
patterns associated with common pathological cardiac conditions sine and cosine transformations often yield unsatisfactory
results. Instead, the correlation function is typically
(ii) Mechanical trauma, for example, being crushed by estimated from the raw ECG data, followed by power
heavy, moving participants during an American spectrum analysis to derive frequency-domain analysis.
football game or other sporting events where This approach, however, is not discussed in detail in this
hormonal levels are elevated article, as much of the verification and validation processes
(iii) Respiratory arrest and ventilatory failure are more are proprietary.
commonly associated with VF than primary organic Several frequency effects measured by the electrodes
cardiac disease are not directly related to cardiac activity. These include
(iv) Many dangerous ventricular arrhythmias, which, noise from electrode movement, respiratory signals,
although resembling asystole hemodynamically and and skeletal muscle activity (electromyogram). Such
electrocardiographically, are finely constructed VF. noise is typically filtered out in the frequency domain.
VF is also prevalent in other mammals, including A notch filter is commonly applied to eliminate frequency
canines, felines, and equines. The most well-known dog interference from equipment and reduce capacitive noise.
breeds that suffer from congenital arrhythmias include the Other common automated diagnostic modalities include
Dalmatian, Boxer, Doberman, and German Shepherd. In derivation of average heart rate, peak heart rate, and low-
mammals, including humans, arrhythmias can also result level heart rate (e.g., recovery after exercise), as well as
from conditions like myocarditis or, more rarely, infective intervals between specific peaks in the PQRSTU complex.
endocarditis (a bacterial infection of the heart valves). More than 30 pathological cardiac rhythm deviations

A common pathological rhythm deviation observed can now be identified using AI-driven analysis. The
in the frequency domain is sinus tachycardia, defined primary method for achieving this level of detail is 12-lead
as a sinus rhythm exceeding 100 beats per minute. This ECG monitoring over an extended period (Figure 4). The
condition is often due to a malfunctioning or overactive 12-lead ECG recording provides a three-dimensional
sinus node. It can also occur as a physiological response view of cardiac depolarization, allowing for precise
to physical exercise or psychological stress. When the localization and characterization of abnormalities. 50-66
sinus rhythm becomes irregular, with the longest PP or The approach captures the rotating depolarization
RR intervals exceeding the shortest by 0.16 seconds or vector of the heart, enabling the detection of both spatial

Volume 2 Issue 3 (2025) 119 doi: 10.36922/aih.8468