Sustained Ventricular Tachycardia and Cardiogenic Shock due to Scorpion Envenomation

We describe a case of severe scorpion envenomation in an adult patient, with the presence of very rapid sustained ventricular tachycardia followed by cardiogenic shock, which was reversed by scorpion antivenom administration. Scorpion venom causes cardiac changes that can lead to an environment favoring arrhythmogenesis. 1. Introduction Scorpion stings occur in many areas of the world, mainly in rural regions of countries with a hot climate [1]. A total of 51,457 scorpion stings were reported in Brazil during the year of 2010 [2]. Because of its frequency, the World Health Organization considers scorpion envenomation as the second most important type of poisoning caused by animals around the world [3]. The majority of these incidents are not serious, with local pain being the only clinical manifestation. However, severe complications such as acute pulmonary edema and cardiogenic shock can occur, mainly in children [1, 4]. We report here an unusual presentation of a case of severe scorpion envenoming complicated by acute pulmonary edema and cardiogenic shock in an adult patient, with the presence of very rapid sustained ventricular tachycardia during the early phase. 2. Case Presentation A 25-year-old woman with no previous disease was admitted to an emergency department after being stung in a toe by an unidentified animal when she was walking at night in a place infested with scorpions in an urban area near the local cemetery. A few minutes after the sting, she had important local pain and paresthesia of her entire left leg associated with several episodes of emesis, profuse sweating, mild respiratory distress, hypertension, and tachycardia. She first sought primary medical care, with clinical examination showing blood pressure of ？mm？Hg and a heart rate of 156？bpm. The electrocardiogram showed sustained ventricular tachycardia with very fast heart rate of approximately 300？bpm associated with a right bundle branch block pattern (Figure 1(a)). Amiodarone was initiated and the sinus rhythm was restored after some minutes, with the patient then being taken to our hospital. During this initial evaluation, no analgesics or antihypertensive agents were administered. Figure 1: Electrocardiogram of a 25-year-old woman showing an episode of sustained ventricular tachycardia (SVT) with very fast heart rate (approximately 300？bpm) after scorpion envenomation (a). Upon admission to the hospital, the electrocardiogram showed sinus tachycardia associated with QTc interval prolongation (550？ms) after SVT reversal (b). A chest radiograph shows pulmonary edema with a