Serum potassium is a critical risk factor for cardiac arrhythmias in acute heart failure patients treated with levosimendan: A retrospective study in a cohort of 250 patients

Objectives: This study aimed to investigate the risk factors associated with developing cardiac arrhythmias in patients with acute heart failure treated with levosimendan. Materials and methods: A retrospective analysis was conducted in patients diagnosed with acute heart failure or acute exacerbation of chronic heart failure treated with levosimendan. The patients were divided into arrhythmia and non-arrhythmia groups based on the presence of rapid-type arrhythmias. Logistic regression analysis was used to identify independent risk factors for levosimendan-induced arrhythmias. Results: Among the 250 patients, 49 (19.60%) experienced nine types of cardiac arrhythmias, the most common being atrial fibrillation (28.57%). The highest incidence of arrhythmias occurred within 48 hours of levosimendan infusion (77.6%). Multivariate analysis indicated that the lowest serum potassium concentration within 5 days after drug administration (odds ratio (OR) 0.410, p = 0.010, 95% confidence interval (CI) 0.209-0.805), micro-pump speed of > 0.2 mu g/kg/min (OR 3.106, p = 0.039, 95% CI 1.584-11.789), and concomitant use of drugs that prolong the QT interval (OR 4.226, p = 0.001, 95% CI 1.850-9.657) were independent risk factors for levosimendaninduced arrhythmias. The incidence of arrhythmias increased when the lowest serum potassium concentration within 5 days after drug administration was below 3.94 mmol/L. Conclusion: This study identified risk factors associated with levosimendan-induced arrhythmias. Clinicians should monitor at-risk patients when administering levosimendan. When using levosimendan in clinical practice, it is necessary to maintain a serum potassium concentration above 3.94 mmol/L.