title: Heart conduction disturbances and cardiovascular collapse after disopyramide and low-dose metoprolol in a patient with hypertrophic obstructive cardiomyopathy.
abstract: Disopyramide as an antiarrhythmic can be prescribed to patients with atrial fibrillation and, owing to its negative inotropic effect, to patients with hypertrophic obstructive cardiomyopathy. It is known that in patients with cardiac conduction disturbances and heart failure, disopyramide can adversely affect heart rhythm and conduction and induce cardiovascular collapse. A patient with hypertrophic obstructive cardiomyopathy and paroxysms of atrial fibrillation is described who was treated with disopyramide and also, during the 5 days before admission, with metoprolol. In spite of normal cardiac conduction and function before disopyramide, this treatment was followed by hypotension, bradycardia, and cardiac conduction disturbances. Our case shows the potential for disopyramide, especially when combined with metoprolol, to induce grave adverse effects even in patients with normal cardiac conduction and ventricular function.
authors.affiliation: Center for Intensive Internal Medicine, University Medical Center Ljubljana, Slovenia.
authors.forename: A
authors.initials: A
authors.lastname: Pernat
authors.forename: B
authors.initials: B
authors.lastname: Pohar
authors.forename: M
authors.initials: M
authors.lastname: Horvat
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000175:diagnosis; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000503:physiopathology; D004206:Disopyramide / Q000008:administration & dosage / Q000009:adverse effects*; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D004562:Electrocardiography; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000008:administration & dosage / Q000009:adverse effects*; D008875:Middle Aged; D012769:Shock / Q000139:chemically induced*
chemical_list: D000889:Anti-Arrhythmia Agents; D008790:Metoprolol; D004206:Disopyramide