Levosimendan and dobutamine have a similar profile for potential risk for cardiac arrhythmias during 24-hour infusion in patients with acute decompensated heart failure

Objectives: Unlike traditional inotropic agents, levosimendan is thought to have a lower potential to induce arrhythmias because it does not increase intracellular calcium levels and myocardial oxygen consumption. We compared the potential effect of levosimendan and dobutamine to induce cardiac arrhythmias in patients with decompensated heart failure.
Study design: Fifty patients with acute decompensated heart failure (NYHA class III-IV, ejection fraction <35%) who were in need of inotropic support were randomized to dobutamine (n=25; mean age 69±10 years) or levosimendan (n=25; mean age 67.5±11.5 years) and underwent 24-hour Holter monitoring before and during inotropic infusion. Holter recordings were analyzed with respect to heart rate (HR), ventricular premature contraction (VPC), couplets of VPC, supraventricular premature contraction (SVPC), paroxysmal atrial fibrillation (PAF), and nonsustained ventricular tachycardia (NSVT).
Results: Before infusions, the two groups were similar with respect to HR, VPC, couplets of VPC, SVPC, and PAF episodes, but the number of NSVT episodes was significantly higher in the levosimendan group. Heart rate and the number of VPCs increased significantly during infusions of levosimendan (p=0.036 and p<0.001, respectively) and dobutamine (for both p<0.001). Increase in couplets of VPC was significant only with dobutamine (p=0.012). The episodes of NSVT and PAF increased with levosimendan, without reaching significance. Levosimendan and dobutamine groups were similar in terms of percentage changes in arrhythmias (55±224% vs. 11±16% for VPC; 2±2.7% vs. 12±9% for couplets of VPC; 3.4±5.8% vs. 16±39% for SVPC, 0.4±2.8% vs. -2±0% for NSVT) and percentage change in total arrhythmias (41±190% vs. 18±35.4%), and the mean HR, VPC, couplets of VPC, SVPC, and episodes of NSVT and PAF (p>0.05).
Conclusion: Our findings suggest that levosimendan and dobutamine have a similar profile for potential risk for cardiac arrhythmias.

Keywords: Arrhythmias, cardiac/etiology, dobutamine/therapeutic use; electrocardiography, ambulatory; heart failure/drug therapy; pyridazines/therapeutic use/adverse effects