Did a viral infection cause the fluctuations in heart rate, from tachycardia (100-115 beats per minute) to bradycardia (67 beats per minute), in a patient with minor flu-like symptoms and a resting heart rate of 83-88 beats per minute?

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Differential Diagnosis

  • Single most likely diagnosis
    • Viral infection: The patient's symptoms of a minor flu-like illness, followed by an improvement in symptoms after a few days, are consistent with a self-limiting viral infection. The fluctuations in heart rate may be attributed to the body's response to the infection.
  • Other Likely diagnoses
    • Dehydration: Although the patient consumed 1 liter of horsetail tea, dehydration could still be a contributing factor, especially if the patient was not drinking enough fluids prior to consuming the tea. Dehydration can cause fluctuations in heart rate.
    • Anxiety or stress: The patient's heart rate increased from 100 to 115, which could be attributed to anxiety or stress. The sudden drop in heart rate during sleep may indicate a decrease in stress or anxiety levels.
    • Horsetail tea effects: Horsetail tea is a diuretic and may cause dehydration, leading to fluctuations in heart rate. However, the exact effects of horsetail tea on heart rate are not well-studied.
  • Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
    • Cardiac arrhythmia: Although the patient's heart rate fluctuations may seem minor, it is essential to rule out any underlying cardiac arrhythmias, which can be life-threatening if left untreated.
    • Myocarditis: Viral infections can cause myocarditis, an inflammation of the heart muscle, which can lead to abnormal heart rhythms and even heart failure.
    • Sepsis: Although the patient's symptoms improved, it is crucial to consider sepsis, a life-threatening condition that can occur if the body's response to an infection becomes uncontrolled.
  • Rare diagnoses
    • Thyroid storm: A rare but life-threatening condition that can cause fluctuations in heart rate, although it is typically associated with more severe symptoms.
    • Pheochromocytoma: A rare tumor that can cause episodes of high blood pressure and heart rate, although it is typically associated with more severe symptoms.
    • Autonomic dysfunction: A rare condition that can affect the autonomic nervous system, leading to abnormal heart rate regulation.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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