title: Neonatal life-threatening arrhythmia responding to lidocaine, a probable LQTS3.
abstract: Intrauterine and neonatal manifestations of congenital long QT syndrome (LQTS) are associated with a high cardiac risk. We present a newborn, with antecedents of intrauterine premature ventricular contractions, showing in his surface electrocardiogram (ECG): a QTc of 0.69 ms, 2:1 atrioventricular block, autolimited episodes of ventricular tachycardia and Torsade de Pointes. Intravenous esmolol therapy was started, being only partially effective. Because of the ECG phenotype, a LQTS3 is suspected, and intravenous lidocaine was started, achieving sinus rhythm, a normal QTc and no new episodes of ventricular tachycardia. Lidocaine was substituted for oral mexiletine, and esmolol for propranolol. During the follow-up the patient has remained asymptomatic under therapy with propranolol and mexiletine.
authors.forename: Pedro
authors.initials: P
authors.lastname: Betrián Blasco
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Antúnez Jiménez
authors.forename: Luis Hipólito
authors.initials: LH
authors.lastname: Falcón González
authors.forename: Pedro
authors.initials: P
authors.lastname: Suárez Cabrera
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage*; D006801:Humans; D007231:Infant, Newborn; D008012:Lidocaine / Q000008:administration & dosage*; D008133:Long QT Syndrome / Q000150:complications* / Q000188:drug therapy*; D008297:Male; D016171:Torsades de Pointes / Q000188:drug therapy* / Q000209:etiology*
chemical_list: D000889:Anti-Arrhythmia Agents; D008012:Lidocaine