Zolpidem-triggered atrial fibrillation in a patient with cardiomyopathy: a case report

Abstract

Background: Zolpidem is a non-benzodiazepine hypnotics widely used to manage insomnia. Zolpidem-triggered atrial fibrillation (AF) in patients with cardiomyopathy has never been reported before. Case presentation: A 40-year-old man with Duchenne muscular dystrophy-related cardiomyopathy attempted suicide and developed new-onset AF after zolpidem overdose. One year before admission, the patient visited our clinic due to chest discomfort and fatigue after daily walks for 1 month; both electrocardiography (ECG) and 24-hour Holter ECG results did not detect AF. After administration of cardiac medication (digoxin 0.125 mg/day, spironolactone 40 mg/day, furosemide 20 mg/day, bisoprolol 5 mg/day, sacubitril valsartan sodium tablets 25 mg/day), he felt better. AF had never been observed before this admission via continuous monitoring during follow-up. Sixteen days before admission, the patient saw a sleep specialist and started on zolpidem tartrate tablets (10 mg/day) due to insomnia for 6 months; ECG results revealed no obvious change. The night before admission, the patient attempted suicide by overdose with 40 mg of zolpidem after an argument, which resulted in severe lethargy. At admission, his ECG revealed new-onset AF, so zolpidem was stopped immediately. 9 hours into admission, AFspontaneously terminated into normal sinus rhythm. Results from the ECG on the following days and the 24-hour Holter ECG at 1-month follow-up showed that no AF was detected. Conclusions: Zolpidem is a frequent first choice of medication for insomnia. However, this case suggests zolpidem overdose could increase the risk of AF in patients with cardiomyopathy. Zolpidem could have caused AF via respiratory depression, which leads to acute atrial distension and hypercapnia. These acute transient arrhythmogenic changes during zolpidem overdose can increase vulnerability to AF in patient with pre-existing cardiomyopathy. Thus, the heart rhythm should be monitored when zolpidem is prescribed in patients with cardiomyopathy.