title: Predictors of in-hospital ventricular fibrillation or torsades de pointes in patients with acute symptomatic bradycardia.
abstract: Severe bradyarrythmias remain as an important cause for hospital urgent admission and these patients can suffer potentially lethal complications (such as ventricular fibrillation [VF] and torsades de pointes [TdP]) between hospital admission and final therapy. Incidence and predictors of these tachyarrhythmias have not been well established. We retrospectively studied all consecutive patients (N = 243, age 75 +/- 10 years; 47% men) admitted to the emergency department of a general hospital between January 1998 and July 2000 for symptomatic bradyarrhythmia. Concomitant therapy included diuretics (25%), digitalis (10%), beta-blockers (10%), amiodarone (2%), and verapamil or diltiazem (8%). Syncope was the most frequent symptom at admission (54%). The most prevalent inclusion bradyarrhythmia was > or =second-degree AV block (82%). Eleven patients (4.5%) presented VF or TdP. Univariate predictors for these complications were previous amiodarone or diuretic intake, presentation as syncope, low serum potassium level, and longer QTc at admission. Multivariate analysis with logistic regression showed only therapy with diuretics and/or amiodarone and QTc at admission as significant predictors for TdP or VF development. Incidence of VF or TdP in patients admitted for symptomatic bradyarrhythmia is relatively important. A prolonged QTc interval and/or therapy with amiodarone or diuretics can predict their presentation.
authors.affiliation: Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain. odiazcastro@hotmail.com
authors.forename: Oscar
authors.initials: O
authors.lastname: Díaz-Castro
authors.forename: Alberto
authors.initials: A
authors.lastname: Puchol
authors.forename: Jesus
authors.initials: J
authors.lastname: Almendral
authors.forename: Esteban G
authors.initials: EG
authors.lastname: Torrecilla
authors.forename: Angel
authors.initials: A
authors.lastname: Arenal
authors.forename: Manuel
authors.initials: M
authors.lastname: Martínez-Selles
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000638:Amiodarone / Q000009:adverse effects; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects; D001919:Bradycardia / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D016171:Torsades de Pointes / Q000139:chemically induced / Q000209:etiology* / Q000503:physiopathology; D014693:Ventricular Fibrillation / Q000139:chemically induced / Q000209:etiology* / Q000503:physiopathology
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone