ST-segment elevation and ventricular tachycardia after ingestion of a common ornamental plant—a case report

Abstract

Japanese yew is a widely used ornamental plant. However, most people are unaware that it is also a poisonous plant. It has potent cardiac toxicities that can lead to sudden cardiac death. A 37-year-old female patient presented to the emergency room with altered mental status and sustained ventricular tachycardia (VT). Electrocardiogram (ECG) after cardioversion showed profound QRS prolongation and ST-segment elevation suggestive of either hyperkalaemia, acute myocardial ischaemia, or Brugada syndrome. Her electrolytes and coronary angiography were normal. After improvement of the patient's mental status, she admitted that she has been consuming Japanese yew from her yard for several months. Few hours later, QRS duration normalised, but mild ST-segment elevation persisted in the right pre-cordial leads, making it more suspicious for Brugada syndrome. However, a procainamide challenge test and electrophysiology study failed to induce typical Brugada pattern ECG and VT. The absence of coronary artery disease and electrolytes disturbances points toward the fact that her arrhythmia and ECG changes are secondary to yew intoxication. The patient was monitored for a few days. She was haemodynamically stable and has not had any arrhythmia. This case highlights the importance of public awareness of severe toxicity from Japanese yew or other yew plants. Yews contain taxines that are responsible for the ECG abnormalities due to its inhibitory effect on the cardiac sodium and calcium channels. They cause conduction abnormalities, VT, and ST-segment elevation that can resemble acute myocardial infarction, hyperkalaemia, and Brugada syndrome.

Taxus baccata intoxication: the sun after the electrical storm

“…Taxines, particularly taxine B, are cardiac myocyte calcium and sodium channel antagonists that inhibit calcium and sodium channels in the same manner as drugs such as verapamil, although taxines are more potent and cardioselective. ( 3 ) This cardiotoxicity is manifested by negative inotropism and an atrioventricular conduction delay that increases the electrocardiographic QRS complex duration; the P wave can also be absent, as seen in the first ECG. The QRS width can be explained by the degree of inhibition of the fast cardiac sodium channels during phase 1 of the action potential.…”

“…( 2 ) The taxine alkaloids block sodium and calcium channels and disrupt sodium-potassium transport, such as digitalis glycosides, which could progress to life-threatening arrhythmia. ( 3 )…”

Relationship Between Brugada Syndrome and Poisoning

“…The patient promptly received electric cardioversion. The baseline ECG, 10 minutes after cardioversion, showed junctional rhythm with a rate of 62 beats/min and severe prolongation of the QRS complex with some Brugada-like pattern [28]. In another report, 52-year-old man presented to the emergency department with nausea, abdominal discomfort, and extreme fatigue after ingestion of 15 g of yew leaves 20 hours before admission.…”

Clinical Toxicology of Yew Poisoning

“…A total of 26 case reports of acute yew poisoning were identified in our literature search (see Table 2). 15-40 Of the 26 cases, 9 (35%) were female and 17 (65%) male, with an average age of 30 years (range = 19 months to 55 years). Surprisingly, only 2 case reports 15,16 in our series (8%) were accidental poisonings, with the rest being deliberate ingestions.…”