The Claim
In patients without structural heart disease, paroxysmal atrial fibrillation occurring during the daytime is associated with a significant increase in the low-frequency to high-frequency heart rate variability ratio before onset and a decrease after termination, indicating a shift toward sympathetic predominance during daytime episodes.
What the research says
Supports is higher
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In people without structural heart disease, daytime episodes of irregular heart rhythm are accompanied by a measurable increase in sympathetic nervous system activity before the episode starts and a decrease after it ends.
See the scientific wording
In patients without structural heart disease, paroxysmal atrial fibrillation occurring during the daytime is associated with a significant increase in the low-frequency to high-frequency heart rate variability ratio before onset and a decrease after termination, suggesting a role for sympathetic predominance in daytime episodes.
During the day, increased nerve signals from the sympathetic nervous system cause the heart's upper chambers to release more calcium, which creates abnormal electrical sparks that start irregular heartbeats. When the nerve signals stop, calcium levels drop and the heart returns to a normal rhythm.
What the research says
1 studyIn people with no heart disease, when their heart starts beating irregularly during the day, their body’s 'speed-up' signals (sympathetic nervous system) get stronger right before it happens and then calm down after it stops. This study found exactly that pattern.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.