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Transient Complete Atrioventricular Block Associated With Herbal Supplement Use.

Ugur Kucuk¹, Melissa Pham², Mohummad Hassan Raza Raja³

¹Department of Internal Medicine, University of South Dakota Sanford School of Medicine, Sioux Falls, South Dakota.

South Dakota Medicine : the Journal of the South Dakota State Medical Association

|September 21, 2023

Summary

Certain herbal supplements can cause dangerous heart rhythm problems like complete AV block and QT prolongation. Discontinuing the supplement quickly restored normal heart rhythm in a young patient.

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Area of Science:

Cardiology
Pharmacology
Herbal Medicine

Background:

Easy access to herbal supplements presents challenges in identifying adverse cardiac events.
This case highlights potential risks of over-the-counter (OTC) supplements in otherwise healthy individuals.

Observation:

A 25-year-old female presented with fatigue and lightheadedness.
Electrocardiogram revealed complete atrioventricular (AV) block with junctional escape rhythm and QT prolongation.
Symptoms emerged after initiating a herbal supplement (Muscle Eze Advanced) for muscle cramps.

Findings:

Extensive cardiac workup, including blood tests and echocardiography, yielded normal results.
Discontinuation of the herbal supplement led to spontaneous restoration of normal sinus rhythm within 24 hours.
The supplement contained ingredients like Melissa officinalis and Valeriana officinalis, known for negative chronotropic, dromotropic, and QT-prolonging effects.

Implications:

Recognizing the link between specific OTC supplements and brady-arrhythmias is crucial.
This association may prevent the need for permanent pacemakers, particularly in younger populations.
Clinicians should inquire about herbal supplement use in patients presenting with unexplained arrhythmias.