Current study TCM substance may trigger arrhythmia

A team of scientists has found that the medicinal plant commonly used in traditional Chinese medicine (TCM) - Evodia rutaecarpa - contains two substances that can trigger cardiac arrhythmias.

TCM Plant triggers heart disorders. Image: Floor Photo Design Fotolia

Extracts of the plant Evodia rutaecarpa are used in TCM for various ailments, i.a. for headaches, gastrointestinal complaints, nausea and vomiting, menstrual disorders and ulcers (ulcers) in the mouth area.

A research team investigated the effects of Evodia extracts. The natural products dehydroevodiamine (DHE) and hortiamin isolated from Evodia proved to be very potent inhibitors of potassium channels in the heart muscle, so-called HERG channels. If HERG channels are blocked, the excitation processes in the heart muscle change, which can trigger severe arrhythmias - so-called torsade de pointes (TdP) - and ventricular fibrillation and can lead to sudden cardiac death.

The emergence of severe TdP arrhythmias after administration of DHE was confirmed by scientists from the University of Utrecht in ECG examinations on dogs.

Further investigations showed that the two natural substances cause oscillations of the membrane potential even at very low concentrations, which can cause cardiac arrhythmias. For example, there is a likelihood that these substances will be converted into a tea made from Evodia fruits. This would involve a considerable risk to the patient.

There are currently no clinical studies investigating the incidence of cardiac arrhythmias after taking Evodia.

Studies at the University of Basel have also shown that the DHE content of Evodiafrüchten is significant. The extent to which these substances enter a tea preparation is currently under investigation. If DHE and Hortiamin are detected, the safety of Evodia preparations should be reassessed.

The authors of the study therefore urge increased vigilance regarding possible arrhythmogenic effects of Evodia preparations. The publication is available at the following link. (sb, pm)