Objectives: Levosimendan improves left ventricular hemodynamic function in patients with cardiogenic shock. However, its impact on right ventricular performance has not been determined. We compared the hemodynamic effects of levosimendan on left and right ventricular function in patients with intractable cardiogenic shock following myocardial infarction.
Design: Observational hemodynamic study.
Setting: Tertiary care center university hospital.
Patients: Fifty-six patients with cardiogenic shock secondary to myocardial infarction were treated with percutaneous revascularization (including intra-aortic balloon pump when appropriate) and commenced on conventional inotropic therapy.
Intervention: Twenty-five consecutive patients with cardiogenic shock due to myocardial infarction who had not improved sufficiently with conventional therapy (including dobutamine and norepinephrine) received levosimendan (as a bolus of 12 microg/kg per minute for 10 mins then 0.1 microg/kg per minute--0.2 mug/kg per minute) as "bail-out" therapy for 24 hrs while invasive hemodynamic parameters were recorded.
Measurements and main results: Levosimendan therapy was associated with a significant increase in cardiac index from 2.1 +/- 0.1 to 3.0 +/- 0.2 L x min x m (p < .01). In addition, levosimendan enhanced right ventricular cardiac power index (0.14 +/- 0.19 to 0.18W +/- 0.12, p < .001), while pulmonary vascular resistance fell from 227.7 +/- 94.5 to 178.1 +/- 62.3 dyne x s x cm (p = .002). No significant change in central venous pressure or mean pulmonary artery pressure was observed. The observed hemodynamic improvement was sustained after the levosimendan infusion was stopped.
Conclusions: Levosimendan infusion for cardiogenic shock following acute myocardial infarction improved hemodynamic parameters of right ventricular performance. Furthermore, we describe the use of right ventricular cardiac power index as a hemodynamic parameter of right ventricular performance.