Various morphologies of bidirectional ventricular tachycardia caused by aconite "Torikabuto" poisoning.

A 43-year-old man presented with nausea. The patient developed ventricular fibrillation (VF), which was refractory to antiarrhythmic drugs and defibrillation. A coronary angiogram showed no coronary artery stenosis. We recorded various fatal arrhythmias, including bidirectional ventricular tachycardia (BVT). The presence of multiple types of BVTs that were refractory to drugs such as adenosine triphosphate, isoproterenol, verapamil, propranolol, and pilsicainide, and easily recurred after defibrillation indicated aconite poisoning. After persisting for 24 h, VF spontaneously resolved and sinus rhythm was restored. Laboratory data revealed lethal concentrations of aconitine. To the best of our knowledge, this is the first report of aconite poisoning-induced BVTs manifesting with multiple morphologies on 12-lead electrocardiogram. The arrhythmogenic effects of aconitine are well recognized. In addition to causing VT and VF, aconitine also can cause BVT. Aconitine can lead to delayed afterdepolarization which has an important role in triggering and maintaining BVT. However, in this case, the concentration of aconitine was high enough to render these drugs ineffective. Prompt application of percutaneous cardio-pulmonary support, which was continued until the aconitine was metabolized, proved successful in this case and should be considered as a management approach in cases of severe aconite poisoning.