Flecainide-Induced Torsade de Pointes Successfully Treated with Intensive Pharmacological Therapy

Abstract

Flecainide is a class IC anti-arrhythmic drug that acts by blocking the fast inward sodium channels during phase 0 of action potential. It is used to treat both supraventricular and ventricular arrhythmias. However, flecainide is also a pro-arrhythmic agent, and overdose may cause nausea, vomiting, hypotension, bradycardia, varying degrees of atrioventricular block, tachyarrhythmias (such as torsades de pointes [TdP]), and sustained ventricular tachycardia. These symptoms may result in rapid-onset hypotension, with an associated mortality rate as high as 10%. The management of flecainide overdose includes supportive and pharmacological measures; however, difficult cases have been successfully treated with extracorporeal membrane oxygenation (ECMO) and intra-aortic balloon pumps. The authors present a case of a patient who visited their hospital with flecainide intoxication and life-threatening arrhythmias, including TdP, ventricular tachycardia, and ventricular fibrillation. The patient was successfully treated with intensive pharmacological therapy.

Pharmacological Profile of the Sodium Current in Human Stem Cell-Derived Cardiomyocytes Compares to Heterologous Nav1.5+β1 Model

“…One of the most important targets is the sodium current (I Na ) that generates the primary depolarizing power determining the upstroke of the action potential (AP) in human atria and ventricular myocytes. Effects on this ion channel should be scrutinized, as inhibition or modulation of it can cause severe adverse drug effects associated with arrhythmia (Lu et al, 2010;Jung and Kwak, 2016). This liability is clearly demonstrated in, e.g., the Cardiac Arrythmia Suppression Trial (CAST) of the late eighties demonstrating the proarrhythmogenic complications associated with I Na inhibitors (Cardiac Arrhythmia Suppression Trial (CAST) Investigators, 1989).…”

Successful Use of Lidocaine in the Management of Severe Flécaïne Poisoning Refractory to Conventional Treatment

“…L'étude de Siegers et al, publiée dans la revue Resuscitation en 2010, a suggéré l'utilisation de l'amiodarone comme traitement efficace de la fibrillation ventriculaire réfractaire induite par la flécaïne, ainsi que la lidocaïne dans le traitement des tachycardies ventriculaires soutenues et réfractaires, permettant ainsi d'éviter le recours à l'ECMO [5] . Ces résultats ont été renforcés par l'étude de Jung et al publiée dans l'International Journal of Arrhythmia en 2016, qui a également souligné l'intérêt de la lidocaïne dans les intoxications à la flécaïne [6] . Bien que la lidocaïne soit également un bloqueur des canaux sodiques, il est admis que sa pharmacocinétique, notamment son effet "on/off", lui permet d'avoir un effet compétitif pour le canal sodique, inversant ainsi la toxicité d'autres inhibiteurs plus puissants des canaux sodiques, tels que les agents de classe Ic comme la flécaïne [7] .…”

“…However, in refractory cases, the use of extracorporeal clearance techniques such as ECMO may be necessary but is not always available [3] . Unexpectedly, the use of class Ib antiarrhythmics like lidocaine, traditionally contraindicated in this context, has shown potential interest in managing refractory rhythm disturbances related to flécaïne poisoning [4] .…”

First Case of Acute Poisoning with Amiodarone and Flecainide in Attempted Suicide Successfully Managed with Lipid Emulsion Therapy in the Emergency Department: Case Report and Literature Review

“…There are reports of accidental overdose in patients treated chronically with flecainide, especially in elders with hepatic or renal comorbidities, that were resolved in the ICU [32,34,37]. There are also reports of flecainide-induced therapy resistant ventricular fibrillation followed by cardiac arrest, successfully treated with cardiopulmonary resuscitation and advanced life support, where amiodarone was used as part of the protocol [19,29,32]. From the studies analyzed, only in one case of accidental flecainide overdose was the patient managed successfully in the ED with Na bicarbonate [36].…”