Pharmacotherapy for atrial fibrillation in elderly hospitalized patients with comorbid congestive heart failure in australia: A retrospective study

Abstract

Background: Despite the proven effectiveness of antiplatelet and anticoagulation treatment for atrial fibrillation (AF), their use has been suboptimal in practice, particularly in rural areas of Australia. Objective: The aim of this study was to describe medication use in the management of AF in elderly hospitalized patients with comorbid congestive heart failure (CHF). Methods: The hospital records of patients with a diagnosis of AF and CHF were reviewed in a rural Australian medical center. All the patients were hospitalized because of significant systolic ventricular dysfunction. The collected data included age, sex, weight, presenting symptoms of AF, and principle diagnosis on admission; medical history; and history of smoking and alcohol consumption. Electrocardiogram before hospital discharge was also retrieved from patient's medical records and was analyzed by the investigators. Cardiovascular and noncardiovascular drugs administered during the hospital stay and at discharge were also documented. Comparison of antiarrhythmic and anticoagulant drugs was made between patients who had AF while hospitalized and those who had a history of AF but were in sinus rhythm while hospitalized. When patients had ≥2 moderate risk factors (eg, age ≥75 years, hypertension, CHF, left ventricular ejection fraction ≤35%, diabetes mellitus) or ≥1 high risk factor (eg, previous stroke, transient ischemic attack or embolism, mitral valve stenosis, or prosthetic heart valve), they were defined as being eligible for anticoagulation treatment. Results: One hundred forty patients (74 men, 66 women; mean [SD] age, 77.1 [6.9] years; all were white) had a diagnosis of AF and were selected for the study. Of these, 92 patients (65.7%) (47 women, 45 men; mean [SD] age, 77.4 [9–2] years) had continuous AF and 48 patients (34.3%) (29 men, 19 women; mean [SD] age, 76.3 [12.4] years) had a history of AF but were in sinus rhythm at admission and discharge. The most commonly used antiarrhythmic drug was digoxin, which was prescribed significantly more frequently in the AF group than in the history of AF group (50 (54.3%] vs 14 [29.2%]; P < 0.01). Amiodarone was prescribed significantly less frequently in the continuous AF group than in the group with a history of AF (7 [7.6%] vs 19 [39−6%]; P < 0.01). There was no significant between-group difference in the use of β-blockers (26 [28.3%] vs 19 [39−6%]), verapamil/diltiazem (9 [9–8%] vs 3 [6.3%]), or Sotalol (2 [2.2%] vs 4 [8.3%]). The mean (SD) resting heart rate for the 140 study patients was 91 (27) bpm. The mean resting heart rate for the patients with AF was significantly higher at admission than at discharge (97 [28] vs 79 [19] bpm; P < 0.01). Of the 110 patients who were eligible for anticoagulation treatment, 64 (58.2%) were prescribed warfarin at discharge. Eligible patients not receiving oral warfarin were significantly older than those who did receive warfarin (79−7 [9−0] vs 75.8 [9.0] years; P = 0.02). Conclusions: In these elderly hospitalized Australian patients with AF and CHF, digoxin, β-blockers, and amiodarone were the most commonly used antiarrhythmic drugs. Anticoagulation treatment was prescribed in ~60% of these patients.