Levosimendan improves hemodynamics and coronary flow reserve after percutaneous coronary intervention in patients with acute myocardial infarction and left ventricular dysfunction

Meta-Analysis of Placebo-Controlled Trials of Levosimendan in Acute Myocardial Infarction

The treatment of acute myocardial infarction is early revascularization. Heart failure and cardiogenic shock may complicate acute myocardial infarction despite applying the best available strategy. Levosimendan is a relatively new drug to treat heart failure with a peculiar mechanism of action: calcium sensitization of myocardial fibres. Levosimendan has a direct inotropic effect but also pleiotropic effects; through the K+ATP channel's opening, it also has a vasodilator effect which may participate concretely in the global effects of the drug. The focus of the literature is on the anti-heart failure and anti-cardiogenic shock properties of Levosimendan, but it may have effects also preventing the development of myocardial insufficiency in acute myocardial infarction. The aim of the meta-analysis is to evaluate the effect of Levosimendan on acute myocardial infarction in placebo-controlled trials. Based on the eight studies selected, we found a beneficial effect of Levosimendan on acute and long-term mortality of patients affected by acute myocardial infarction. With caution in interpreting the results of this meta-analysis, our data support the idea that Levosimendan may already have a role in the treatment of acute ischemic heart disease. Further studies specifically designed to investigate the early role in the treatment of ischemic heart failure are needed.

Evidence and Current Use of Levosimendan in the Treatment of Heart Failure: Filling the Gap

Levosimendan is a distinctive inodilator combing calcium sensitization, phosphodiesterase inhibition and vasodilating properties through the opening of adenosine triphosphate-dependent potassium channels. It was first approved in Sweden in 2000 for the short-term treatment of acutely decompensated severe chronic heart failure when conventional therapy is not sufficient, and in cases where inotropic support is considered appropriate. After more than 20 years, clinical applications have considerably expanded across critical care and emergency medicine, and levosimendan is now under investigation in different cardiac settings (eg, septic shock, pulmonary hypertension) and for non-cardiac applications (eg, amyotrophic lateral sclerosis). This narrative review outlines key milestones in levosimendan history, by addressing regulatory issues, pharmacological peculiarities and clinical aspects (efficacy and safety) of a drug that did not receive great attention in the heart failure guidelines. A brief outlook to the ongoing clinical trials is also offered.

Rationale, experimental data, and emerging clinical evidence on early and preventive use of levosimendan in patients with ventricular dysfunction

Acute ventricular dysfunction (AVD) is a complex condition with substantial morbidity and mortality, still featuring unique therapeutic challenges. Levosimendan is a calcium sensitizer and ATP-dependent potassium channel opener that was developed as an inodilating drug for the treatment of acute heart failure and cardiogenic shock. Differently from other more widely used inotropic agents, levosimendan has some exclusive characteristics, in terms of mechanisms of action, pharmacodynamic profile, and haemodynamic effects. This may have important clinical implications. In particular, in patients with AVD or in patients with pre-existing severe ventricular impairment undergoing planned myocardial stress, the administration of levosimendan before the onset of overt symptoms or before cardiovascular therapeutic procedures may have the potential to bridge the patient through the critical phase. In this review, we will focus on the rationale, the existing experimental data, and the emerging clinical experience supporting an early, even preventive use of levosimendan in severe ventricular dysfunction, beyond its recognized indications.

Hemodynamic effects of inotropic drugs in heart failure: A network meta-analysis of clinical trials

BACKGROUND

There is currently no consensus on the appropriate selection of inotropic therapy in ventricular dysfunction. The objective of the study was to detect the effects of different inotropes on the hemodynamics of patients who developed low cardiac output.

METHODS

PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched (all updated December 31, 2017). The inclusion criteria were as follows: low cardiac index (CI < 2.5 L/min/m) or New York Heart Association class II-IV, and at least 1 group receiving an inotropic drug compared to another group receiving a different inotropic/placebo treatment. The exclusion criteria were studies published as an abstract only, crossover studies, and studies with a lack of data on the cardiac index.

RESULTS

A total of 1402 patients from 37 trials were included in the study. Inotropic drugs were shown to increase the cardiac index (0.32, 95%CI:0.25, 0.38), heart rate (7.68, 95%CI:6.36, 9.01), and mean arterial pressure (3.17, 95%CI:1.96, 4.38) than the placebo. Overall, the pooled estimates showed no difference in terms of cardiac index, heart rate, mean arterial pressure, systemic vascular resistance, and mean pulmonary arterial pressure among the groups receiving different inotropes.

CONCLUSIONS

Our systematic review found that inotrope therapy is not associated with the amelioration of hemodynamics. An accurate evaluation of the benefits and risks, and selection of the correct inotropic agent is required in all clinical settings.

Use of levosimendan in acute heart failure

As a calcium sensitizer and inodilator that augments cardiac contractility without increasing myocardial oxygen demand or exacerbating ischaemia, levosimendan may be well configured to deliver inotropic support in cases of acute heart failure (AHF). Other factors favouring levosimendan in this setting include its extended duration of action due to the formation of an active metabolite and the lack of any attenuation of effect in patients treated with beta-blockers. Effects of levosimendan on systemic haemodynamics include its significant, dose-dependent increases in cardiac output, stroke volume and heart rate, and decreases in right and left ventricular filling and total peripheral resistance. Rapid and sustained reduction in levels of natriuretic peptides is a consistent effect of levosimendan use and potentially favourable effects on other neurohormonal indicators of cardiac distress are also observed. Levosimendan has repeatedly been shown to be effective in relief of symptoms of AHF, notably dyspnoea and fatigue, while mortality data from clinical trials and registries suggest that levosimendan is markedly less likely than catecholaminergic inotropes to worsen prognosis. The vasodilator pharmacology of levosimendan is also pertinent to the drug’s use in AHF, in which setting organ under-perfusion is often a key pathology. These considerations suggest that levosimendan may have a more favourable impact on the circumstances of the majority of AHF patients than adrenergic agents that act only or primarily as cardiac stimulants. They also suggest that levosimendan may advantageously be integrated into a comprehensive strategy of early intervention designed and intended to prevent cardiac destabilization worsening to the point where hospitalization is necessary. Levosimendan should be used with caution and with tightened haemodynamic monitoring in patients who have low baseline blood pressure (systolic blood pressure <100 mmHg; diastolic blood pressure <60 mmHg), or who are at risk of a hypotensive episode.

Effects of Levosimendan on Patients with Heart Failure Complicating Acute Coronary Syndrome: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The prognosis for patients with heart failure (HF), including cardiogenic shock (CS), complicating acute coronary syndrome (ACS) remains poor.

OBJECTIVE

This study aimed to review the relevant literature and evaluate whether levosimendan was associated with better clinical outcomes in these patients.

METHODS

We searched PubMed, EMBASE, and the Cochrane library databases for randomized controlled trials that investigated levosimendan compared with any control in patients with HF/CS complicating ACS.

RESULTS

A total of 1065 patients from nine trials were included in this study. Analysis showed that levosimendan significantly reduced total mortality and the incidence of worsening HF. In patients with HF-ACS, levosimendan was associated with reduced mortality. In patients with CS-ACS, no significant difference was observed between the two groups. Levosimendan contributed to significantly reduced mortality when compared with placebo, but no significant reduction was seen compared with dobutamine. Compared with controls, levosimendan decreased pulmonary capillary wedge pressure and systemic vascular resistance and increased cardiac index, with no significant difference observed between the groups in terms of heart rate. Levosimendan non-significantly increased the risk of hypotension but did not increase the risk of ischemic episodes, sinus tachycardia, atrial fibrillation, or ventricular arrhythmias.

CONCLUSION

Levosimendan appears to be a promising drug to reduce mortality and worsening HF in patients with HF/CS-ACS. It appears to provide hemodynamic benefit and was associated with an increased risk of hypotension.

The role of levosimendan in acute heart failure complicating acute coronary syndrome: A review and expert consensus opinion

Acute heart failure and/or cardiogenic shock are frequently triggered by ischemic coronary events. Yet, there is a paucity of randomized data on the management of patients with heart failure complicating acute coronary syndrome, as acute coronary syndrome and cardiogenic shock have frequently been defined as exclusion criteria in trials and registries. As a consequence, guideline recommendations are mostly driven by observational studies, even though these patients have a particularly poor prognosis compared to heart failure patients without signs of coronary artery disease. In acute heart failure, and especially in cardiogenic shock related to ischemic conditions, vasopressors and inotropes are used. However, both pathophysiological considerations and available clinical data suggest that these treatments may have disadvantageous effects. The inodilator levosimendan offers potential benefits due to a range of distinct effects including positive inotropy, restoration of ventriculo-arterial coupling, increases in tissue perfusion, and anti-stunning and anti-inflammatory effects. In clinical trials levosimendan improves symptoms, cardiac function, hemodynamics, and end-organ function. Adverse effects are generally less common than with other inotropic and vasoactive therapies, with the notable exception of hypotension. The decision to use levosimendan, in terms of timing and dosing, is influenced by the presence of pulmonary congestion, and blood pressure measurements. Levosimendan should be preferred over adrenergic inotropes as a first line therapy for all ACS-AHF patients who are under beta-blockade and/or when urinary output is insufficient after diuretics. Levosimendan can be used alone or in combination with other inotropic or vasopressor agents, but requires monitoring due to the risk of hypotension.

Effect of baseline characteristics on mortality in the SURVIVE trial on the effect of levosimendan vs dobutamine in acute heart failure: Sub-analysis of the Finnish patients

BACKGROUND

In the SURVIVE trial, including 1327 acute heart failure patients, no statistically significant difference between levosimendan and dobutamine in the 180-day all-cause mortality was seen. Country-specific differences in outcome were, however, present. In the Finnish sub-population in fact, mortality was significantly lower in levosimendan treated patients. We aim to understand the reasons for this disparity.

METHODS

The risk factors for all-cause mortality were identified in the whole study population using multivariate Cox proportional hazards regression analysis. Those factors were evaluated in the 95 patients of the Finnish sub-population.

RESULTS

The treatment by country interaction for mortality in Finland vs. other countries was significant, p=0.029. Levosimendan treated patients had a lower 180-day mortality compared to dobutamine treated (17% vs. 40%, p=0.023) in the Finnish sub-population. Baseline variables predicting survival in the whole SURVIVE trial population included age, systolic blood pressure, heart rate, myocardial infarction during admission, levels of NT-pro-BNP, glucose, creatinine, and alanine transferase, use of ACE inhibitors and β-blockers, oliguria, time from hospital admission to randomization, history of cardiac arrest, and left ventricular ejection fraction. Finnish patients were more frequently treated with β-blockers (88% vs. 52%, p<0.0001), their study treatment was started earlier (mean±SD 41±40h vs. 81±154; p<0.0001), and they had more often acute myocardial infarction at admission (39% vs. 16%, p<0.0001).

CONCLUSION

The lower mortality in the Finnish patients treated with levosimendan was associated with higher use of β-blockers, higher frequency of myocardial infarction at admission, and shorter delay between randomization and start of treatment.

Inotropes for the management of acute heart failure patients with renal dysfunction. Still an option?

INTRODUCTION

Renal dysfunction is highly prevalent in patients with acute heart failure (AHF). These patients are more vulnerable in worsening of kidney function and have also higher mortality rates.

AREAS COVERED

Recent developments in the understanding of bidirectional interaction between heart and kidney are reviewed in the context of the potential impact of inotropes on renal function. Key clinical trials reporting the use of inotropes in AHF patients with renal dysfunction are discussed in this review.

EXPERT OPINION

Inotropes may be indicated on a short-term basis and under close monitoring in AHF with renal dysfunction mostly in cases of low output heart failure that can provoke renal hypoperfusion. Dopamine administration with low dose of i.v. furosemide has been recently compared with high dose of i.v. furosemide alone, demonstrating lower rates of worsening renal function and electrolyte disturbances. Moreover, small clinical trials have shown that the novel inodilator levosimendan seems to be superior to dobutamine or placebo in improving renal function in patients with acutely decompensated heart failure. The impact of novel inotropes on kidney function is still unclear. Randomized clinical trials are required in order to identify the role of inotropes in the management and/or prevention of acute cardiorenal syndrome.

Management of acute cardiac failure by intracoronary administration of levosimendan

Acute cardiac failure caused by myocardial infarction or inadequate cardioprotection during heart surgery is associated with increased mortality and morbidity. Levosimendan is a new drug used in heart failure though it is limited by the systemic hypotension, which develops with intravenous administration. Intracoronary (IC) administration however should affect systemic circulation less while maintaining the beneficial cardiac effects of the drug. We herewith report the results from the first such clinical series. Levosimendan was administered IC in 33 consecutive patients who developed cardiogenic shock during heart surgery and were unable to wean off cardiopulmonary bypass despite maximal support. Preadministration/postadministration coronary graft flows, hemodynamic parameters, left ventricular function, and metabolic requirements were measured and compared. Levosimendan significantly increased graft flows and improved hemodynamic parameters. Systolic blood pressure (93 ± 26.4 vs. 106 ± 18.2 mm Hg, P < 0.05) and cardiac index (2.0 ± 0.5 vs. 3.1 ± 0.2, P < 0.001) were increased, whereas systemic vascular resistance (1470.7 ± 114 vs. 1195.8 ± 112, P < 0.01) was reduced. Better myocardial perfusion improved metabolic requirements, with myocardial oxygen extraction and glucose uptake increasing by 72% and 74%, respectively, whereas lactate production was reduced by 64%. Echocardiography demonstrated additional ventricular segment recruitment. Therefore, IC Levosimendan administration in acute heart failure is safe and efficacious producing improved cardiac function without significant detrimental hypotension.

Levosimendan and mortality after coronary revascularisation: a meta-analysis of randomised controlled trials

INTRODUCTION

Patients undergoing coronary revascularization often require inotropic support that has been associated with an increased risk for death and morbidity. The purpose of this study was to evaluate the effect of levosimendan versus control on survival after coronary revascularization.

METHODS

A systemic review and meta-analysis of the literature was carried out on published randomized controlled clinical trials that investigated the efficacy of levosimendan compared to other therapy in patients having coronary revascularisaion. The databases searched were Pubmed, EMBASE, the Cochrane Registry of Clinical Trials and the metaRegister of Controlled Trials. Studies that compared levosimendan to any other therapy for coronary revascularisation in adult humans and reported at least one outcome of interest were considered for inclusion. Both percutaneous coronary intervention and cardiac surgery were included. Data extraction was performed independently by two reviewers using predefined criteria. Relevant outcomes included mortality, cardiac index, cardiac enzymes, length of stay and post-procedural atrial fibrillation.

RESULTS

The meta-analysis included 729 patients from 17 studies. Levosimendan was associated with a mortality reduction after coronary revascularization, (19/386 in the levosimendan group vs 39/343 in the control arm) odds ratio (OR) 0.40 (95% confidence interval (CI) 0.21 to 0.76, P for overall effect 0.005, P for heterogeneity = 0.33, I2 = 12% with a total of 729 patients. Levosimendan also had a favourable effect on cardiac index (standardised mean difference 1.63, 95% CI 1.43 to 1.83, P for overall effect < 0.00001), length of intensive care stay (random effects model, mean difference - 26.18 hours 95% CI 46.20 to 6.16, P for heterogeneity < 0.00001, I2 = 95%, P for overall effect P = 0.01), reductions in the rate of atrial fibrillation (OR 0.54, 95% CI 0.36 to 0.82, P for effect = 0.004, P for heterogeneity 0.84, I2 = 0% for 465 patients) and troponin I levels group (mean difference -1.59, 95% CI 1.78 to 1.40, P for overall effect < 0.00001, P for heterogeneity < 0.00001, I2 = 95%). Limitations of this analysis are discussed.

CONCLUSIONS

Levosimendan is associated with a significant improvement in mortality after coronary revascularization. There are also improvements in several secondary endpoints. A suitably powered randomised controlled trial is required to confirm these findings and to address the unresolved questions about the timing and dosing of levosimendan.

Levosimendan in the Treatment of Acute Heart Failure, Cardiogenic and Septic Shock: A Critical Review

Levosimendan is a drug which increases the sensitivity of the heart to calcium and which opens potassium channels, resulting in inodilation. Clinical trial data from patients suffering from heart failure have demonstrated that it improves haemodynamics without increasing intra-cellular calcium or oxygen consumption. However, there is no consistent evidence of mortality reduction. This narrative review summarises the key trials of its use in acute heart failure, acute coronary syndrome, cardiogenic shock and septic shock.

Use of levosimendan in patients with ischemic heart disease following mechanical reperfusion

Cardiac failure is among the most significant conditions associated with acute coronary syndrome. In ischemic heart disease, serious hemodynamic problems are reported in patients with left ventricular dysfunction during the acute phase despite mechanical revascularization. Several positive inotropic agents in addition to intra-aortic balloon pump (IABP) are required to support patients with impaired left ventricular pump function during this phase. Intravenous inotropic agents, beta-mimetics, and phosphodiesterase inhibitors lead to increases in the incidence of arrhythmia and myocardial O(2) consumption owing to their effect of increasing intracellular calcium amount, although they produce rapid hemodynamic improvements in cardiac failure. This causes severe problems particularly in cardiac failure of ischemic origin. Recently, levosimendan, a calcium-sensitizing agent with cardioprotective properties, is being used alone or in combination with IABP in cases with severe left ventricular systolic dysfunction during mechanical revascularization procedures (percutaneous coronary interventions, coronary bypass surgery). This review includes studies with levosimendan in cases not recovering due to myocardial stunning in the acute phase despite mechanical approaches applied.

Comparison of ischemic side effects of levosimendan and dobutamine with integrated backscatter analysis

BACKGROUND

Levosimendan improves cardiac contractility without increasing oxygen consumption. However, its effects on ischemia were not supported with the utilization of a noninvasive parameter of myocardial characterization.

HYPOTHESIS

The changes observed in integrated backscatter (IBS) may be reflective of change in myocardial ischemia. In this study, the effect of levosimendan on ischemia detected by IBS was evaluated in patients with ischemic heart failure (HF).

METHODS

Patients who had LVEF < 40% and NYHA III-IV symptoms of HF were included in this study. Patients were randomized to levosimendan (n = 21), or to dobutamine (n = 25) groups. The cyclic variation of integrated backscatter (CVIBS) was determined as the difference between the maximal and minimal values in a cardiac cycle, average of three consecutive beats. CVIBS was taken from the mid-anteroseptal, mid-inferior, and mid-posterolateral areas of the parasternal short axis images before the drug administration and at the end of the 24-hour infusion period.

RESULTS

Baseline characteristics and concomitant medications were similar in both groups. A significant reduction in CVIBS was detected in anteroseptal (7.6 +/- 1.4 dB versus 5.9 +/- 0.8 dB, p = 0.01), inferior wall (7.4 +/- 0.8 dB versus 6.7 +/- 1.5 dB, p = 0.03), and posterolateral wall (9.0 +/- 1.2 dB versus 8.2 +/- 0.6 dB, p = 0.04) after dobutamine administration, while no significant changes were observed in the levosimendan group in all walls.

CONCLUSIONS

Unlike dobutamine, levosimendan may not induce myocardial ischemia as shown by CVIBS at commonly used dosages in the setting of decompensated HF without active ischemia.

New pharmacologic therapies for acute heart failure

Given the limitations of high-dose diuretics and vasodilators and the increasing literature showing that inotropes, regardless of the dose used, have a detrimental effect on mortality, a variety of new agents are under investigation for the treatment of pulmonary and systemic congestion and restoration of cardiac output in the setting of acute heart failure syndromes. The new therapeutic approach is based on two goals: short-term improvement in symptoms together with long-term improvement of cardiac function. This review describes new agents that are in preclinical and in clinical phases with realistic prospects: anti-endothelin, natriuretic peptides, istaroxime, levosimendan, myosin activators, and vasopressin antagonists. Those new therapeutic strategies aim to act at the cellular level to improve vessel and heart functions, with minimal side effects, together with improved sodium and water balance.

Myocardial stunning following no flow ischaemia is diminished by levosimendan or cariporide, without benefits of combined administration

AIM OF THE STUDY

Levosimendan, a calcium sensitiser, and cariporide, a blocker of the Na+/H+ exchanger, decrease necrosis and improve function following myocardial ischaemia. However, their role in myocardial stunning is unclear. We tested the hypothesis that levosimendan, cariporide, or their combination reduce stunning after global myocardial ischaemia.

METHODS

In a prospective, controlled, randomised laboratory study isolated guinea pig hearts (n=48) were perfused in a Langendorff apparatus. Stunning was induced by 20 min of global no-flow ischaemia. Levosimendan (0.1 micromol/l) or cariporide (1 micromol/l) were given either before or after ischaemia, and effects of both drugs combined were also assessed. Left ventricular developed pressure (LVdp) was assessed continuously before ischaemia and for 45 min after reperfusion.

RESULTS

Levosimendan (24+/-7%) and the combination of levosimendan and cariporide (38.7+/-4%) increased LVdp from baseline values before ischaemia, without differences between groups. In contrast, cariporide alone decreased LVdp (-11+/-2%) from baseline. Ischaemia/reperfusion decreased LVdp by about 70% in vehicle treated hearts compared to baseline. Treatment with cariporide, levosimendan, or their combination both before and after ischaemia, and treatment with cariporide after ischaemia caused a 25% greater recovery of LVdp than in control hearts. There were no differences between these groups and no enhanced effect with levosimendan/cariporide combined. In contrast, levosimendan only given after ischaemia did not improve LVdp.

CONCLUSIONS

Cariporide diminished stunning when given before or after ischaemia, while levosimendan was only effective if given before ischaemia. Thus, levosimendan or cariporide may be useful in settings where ischaemia/reperfusion is to be expected.

Hemodynamic improvement following levosimendan treatment in patients with acute myocardial infarction and cardiogenic shock*

OBJECTIVES

Levosimendan, a novel inodilator, has been shown to improve hemodynamic function in patients with acute exacerbation of congestive heart failure. We wanted to determine the hemodynamic effects of levosimendan following ineffective conventional therapy (with catecholamines) in patients with 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 (intra-aortic balloon pump where appropriate) and commenced on conventional inotropic therapy.

INTERVENTIONS

Patients with persisting cardiogenic shock 24 hrs after revascularization were additionally treated with levosimendan (rapid bolus of 12 microg/kg for 10 mins, then 0.05-0.2 mug/kg/min for 24 hrs) (n = 25).

MEASUREMENTS AND MAIN RESULTS

With conventional catecholamine therapy (norepinephrine and dobutamine), we observed only marginal improvement in mean arterial pressure or cardiac index. In contrast, the addition of levosimendan produced a significant increase in cardiac index (2.1 +/- 0.56 to 3.0 +/- 1.11 L/min/m2, p < .01) and cardiac power index (0.32 +/- 0.08 to 0.44 +/- 0.18 W, p < .01), whereas systemic vascular resistance decreased significantly (1208 +/- 333 to 858 +/- 299 dyne.sec.cm(-5), p < .01). There was no significant change in blood pressure during levosimendan treatment. Hemodynamic improvement was sustained after levosimendan infusion was stopped.

CONCLUSIONS

Levosimendan infusion in cardiogenic shock following acute myocardial infarction improved cardiovascular hemodynamics without leading to hypotension.

The cardioprotective effects of levosimendan: preclinical and clinical evidence

Levosimendan, a drug used in the treatment of acute and decompensated heart failure, has positive inotropic and antistunning effects mediated by calcium sensitization of contractile proteins, and vasodilatory and antiischemic effects mediated via the opening of ATP-sensitive potassium channels in vascular smooth-muscle cells. Recently, it also has been shown to act on mitochondrial ATP-sensitive potassium (mitoKATP) channels, an action thought to protect the heart against ischemia-reperfusion damage. This finding has suggested a possible application for levosimendan in clinical situations in which preconditioning would be beneficial (eg, in pre- and perioperative settings in cardiac surgery). The demonstration that levosimendan can prevent or limit myocyte apoptosis via the activation of mitoKATP channels provides a potential mechanism whereby this agent might protect cardiac myocytes during episodes of acute heart failure. This finding may explain why short-term treatment with levosimendan may improve longer-term survival. The present article reviews the literature on the cardioprotective actions of levosimendan, with particular emphasis on its recently recognized effects on mitoKATP channels and the putative preconditioning effects of that action. A therapeutic approach to acute heart failure that includes a cardioprotective strategy could have a clinically meaningful benefit on disease progression beyond alleviation of symptoms.

Effects of levosimendan on coronary artery flow and cardiac performance in patients with advanced heart failure

BACKGROUND

Levosimendan has inotropic and vasodilatory effects. We investigated the effects of levosimendan on coronary flow and associated changes in neurohormonal activation and cardiac performance in patients with advanced heart failure.

METHODS

Forty-two patients with NYHA III-IV and a left ventricular ejection fraction (EF) 25+/-6%, were randomised to levosimendan 0.1 microg/kg/min (n=21) or placebo for 24 h. Before and 24 h after each treatment, we assessed: the maximal velocity (Vmax), time integral (VTI) and deceleration time (DT) of the diastolic coronary flow wave (CF) in LAD using transthoracic Doppler echocardiography, pulmonary artery systolic pressure by Doppler echocardiography, E/E' ratio using Doppler imaging of mitral inflow velocity, tissue Doppler imaging of the mitral annulus and B-type natriuretic peptide (BNP) levels.

RESULTS

By ANOVA, there was a greater increase in CF-Vmax (43+/-23 vs.25+/-8 cm/s), CF-DT (904+/-250 vs. 667+/-151 ms), and EF and a greater decrease in BNP, pulmonary artery systolic pressure and E/E? after levosimendan than after placebo (p<0.05). Compared to baseline, the percent changes in CF-VTI were related to the concomitant changes in EF, E/E?, and BNP after treatment with levosimendan (r=0.69, r=?0.51 and r=?0.80, p<0.05 respectively).

CONCLUSION

Treatment with levosimendan improves coronary flow and microcirculation in parallel with an improvement in cardiac performance and neurohormonal activation in patients with advanced heart failure.

[Role of Levosimendan in intensive care treatment of myocardial insufficiency]

Levosimendan is a calcium sensitizer that is currently in the focus of intensive care medicine because it may be superior to standard inotropic agents in the treatment of acute myocardial insufficiency. The effects of levosimendan mainly depend on three predominant mechanisms: 1) positive inotropic effect by increasing the sensitivity of cardiac myofilaments to calcium ions, 2) vasodilatory effect by stimulation of adenosine triphosphate-sensitive potassium channels and 3) inhibition of phosphodiesterase-III. In a large number of experimental and clinical studies further possible indications for levosimendan have been described, e.g. cardioprotection during ischemia, cardiogenic shock, septic myocardial insufficiency and pulmonary hypertension. This review article critically summarizes the current scientific and clinical knowledge about levosimendan, its pharmacologic characteristics, mechanisms of action as well as indications and potential risks.

Clinical pharmacology of levosimendan

Levosimendan has been developed for the treatment of decompensated heart failure and is used intravenously when patients with heart failure require immediate initiation of drug therapy. It increases cardiac contractility and induces vasodilatation. The pharmacokinetics of levosimendan are linear at the therapeutic dose range of 0.05-0.2 microg/kg/minute. The short half-life (about 1 hour) of the parent drug, levosimendan, enables fast onset of drug action, although the effects are long-lasting due to the active metabolite OR-1896, which has an elimination half-life of 70-80 hours in patients with heart failure (New York Heart Association functional class III-IV). Although levosimendan is administered intravenously, it is excreted into the small intestine and reduced by intestinal bacteria to an amino phenolpyridazinone metabolite (OR-1855). This metabolite is further metabolised by acetylation to N-acetylated conjugate (OR-1896). The circulating metabolites OR-1855 and OR-1896 are formed slowly, and their maximum concentrations are seen on average 2 days after stopping a 24-hour infusion. The haemodynamic effects after levosimendan seem to be similar between fast and slow acetylators despite the fact that the enzyme N-acetyltransferase-2, which is responsible for the metabolism of OR-1855 to OR-1896, is polymorphically distributed in the population. Levosimendan reduces peripheral vascular resistance and has direct contractility-enhancing effects on the failing left ventricle. It also improves indices of diastolic function and seems to improve the function of stunned myocardium. Despite an improvement in ventricular function, levosimendan does not increase myocardial oxygen uptake significantly. An increase in coronary blood flow and a reduction in coronary vascular resistance have been observed. Levosimendan reduces plasma brain natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) levels substantially, and a decrease in plasma endothelin-1 has been observed. Levosimendan also exerts beneficial effects on proinflammatory cytokines and apoptosis mediators. The effects of a 24-hour levosimendan infusion on filling pressure, ventricular function and BNP, as well as NT-proBNP, last for at least 7 days.

A review of levosimendan in the treatment of heart failure

Heart failure is a relatively important public health problem due to its increasing incidence, poor prognosis, and frequent need of re-hospitalization. Intravenous positive inotropic agents play an important role in treating acute decompensation of patients with heart failure due to left ventricular systolic dysfunction. Although frequently used, the inotropic agents β-adrenergic agonists and phosphodiesterase inhibitors seem effective for improving symptoms in the short term; it has been shown that they increase morbidity and mortality by elevating intracellular cyclic adenosine monophosphate (cAMP) and calcium levels. Levosimendan is a new positive inotropic agent having ATP-dependent potassium-channel-opening and calcium-sensitizing effects. In studies on its effects without increasing intracellular calcium concentrations and on its effects that depend on available intracellular calcium levels, it has been shown to have favorable characteristics different from those of current inotropic agents, which exert their effects by increasing calcium concentrations. This study aims to review other important studies about levosimendan by revealing the underlying mechanisms of its activity, efficiency, and safety.

Levosimendan: beyond its simple inotropic effect in heart failure

Classic inotropic agents provide short-term haemodynamic improvement in patients with heart failure, but their use has been associated with poor prognosis. A new category of inotropic agents, the Ca(2+) sensitizers, may provide an alternative longer lasting solution. Levosimendan is a relatively new Ca(2+) sensitizer which offers haemodynamic and symptomatic improvement by combining a positive inotropic action via Ca(2+) sensitization and a vasodilatory effect via adenosine triphosphate(ATP)-sensitive K(+) (K(ATP)), Ca(2+)-activated K(+) (K(Ca)(2+)) and voltage-dependent K(+) (K(V)) channels activation. Levosimendan also seems to induce a prolonged haemodynamic improvement in patients with heart failure as a result of the long half-life of its active metabolite, OR-1896. Furthermore, there is also evidence that levosimendan may have additional antiinflammatory and antiapoptotic properties, affecting important pathways in the pathophysiology of heart failure. Despite the initial reports for a clear benefit of levosimendan on short- and long-term mortality in patients with severe heart failure, the results from the recent clinical trials are rather disappointing, and it is still unclear whether it is superior to dobutamine in affecting survival of patients with severe heart failure. In conclusion, levosimendan is a promising agent for the treatment of decompensated heart failure. As further to its positive inotropic effect, it affects multiple pathways with key roles in the pathophysiology of heart failure. The results of the ongoing trials examining the effect of levosimendan on mortality in patients with heart failure will hopefully resolve the controversy as to whether levosimendan is superior to classic inotropic agents for the treatment of severe heart failure.

The utility of levosimendan in the treatment of heart failure

Calcium sensitizers are a new group of inotropic drugs. Levosimendan is the only calcium sensitizer in clinical use in Europe. Its mechanism of action includes both calcium sensitization of contractile proteins and the opening of adenosine triphosphate (ATP)-dependent potassium channels as mechanism of vasodilation. The combination of K-channel opening with positive inotropy offers potential benefits in comparison to currently available intravenous inotropes, since K-channel opening protects myocardium during ischemia. Due to the calcium-dependent binding of levosimendan to troponin C, the drug increases contractility without negative lusitropic effects. In patients with heart failure levosimendan dose-dependently increases cardiac output and reduces pulmonary capillary wedge pressure. Since levosimendan has an active metabolite OR-1896 with a half-life of some 80 hours, the duration of the hemodynamic effects significantly exceeds the 1-hour half-life of the parent compound. The hemodynamic effects of the levosimendan support its use in acute and postoperative heart failure. Several moderate-size trials (LIDO, RUSSLAN, CASINO) have previously suggested that the drug might even improve the prognosis of patients with decompensated heart failure. These trials were carried out in patients with high filling pressures. Recently two larger trials (SURVIVE and REVIVE) in patients who were hospitalized because of worsening heart failure have been finalized. These trials did not require filling pressures to be measured. The two trials showed that levosimendan improves the symptoms of heart failure, but does not improve survival. The results raise the question whether a 24-hour levosimendan infusion can be used without invasive hemodynamic monitoring.

Effects of Levosimendan on Left Ventricular Diastolic Function After Primary Angioplasty for Acute Anterior Myocardial Infarction: A Doppler Echocardiographic Study

BACKGROUND

Levosimendan is a new Ca-sensitizing drug with combined positive inotropic and vasodilatory effects that offers new therapeutic possibilities in patients with severe heart failure. Compared with other inotropic agents, animal studies demonstrated that levosimendan does not impair left ventricular diastolic function.

OBJECTIVE

We sought to evaluate the effects of levosimendan on left ventricular diastolic function, using conventional transmitral Doppler and Doppler tissue imaging parameters, in patients with anterior acute myocardial infarction undergoing primary angioplasty.

METHODS

After a successful primary angioplasty, we randomized 52 consecutive patients with anterior acute myocardial infarction to levosimendan or placebo infusion and analyzed the diastolic function using conventional transmitral Doppler flow and Doppler tissue imaging at mitral annulus.

RESULTS

At 24 hours after the index intervention, patients treated with levosimendan (n = 26) showed a significant reduction of the isovolumetric relaxation time (114.6 +/- 15.1-69.2 +/- 5.6 milliseconds; P = .001) and the ratio between the early diastolic flow and early tissue velocity (E/E') (21.4 +/- 10.7-12.8 +/- 7.3; P = .04), and a significant increase of the ratio between the early and late diastolic flow (E/A) (0.86 +/- 0.33-1.52 +/- 0.88; P = .03) and E' (6.4-7.9 cm/s; P = .001). On the other hand, only a significant increase in E/A ratio (0.97 +/- 0.32-1.64 +/- 0.51; P = .002) was observed in the placebo group (n = 26).

CONCLUSIONS

Levosimendan, after primary angioplasty in patients with anterior acute myocardial infarction, appears to improve the Doppler echocardiographic parameters of left ventricular diastolic function.

Levosimendan for the treatment of acute heart failure syndromes

Levosimendan is a novel calcium-sensitising agent that has been shown to have beneficial inotropic, metabolic and vasodilatory effects in the treatment of acute and advanced chronic heart failure. Levosimendan binds to troponin-C in cardiomyocytes and, thereby, improves cardiac contractility without disturbing the metabolic status of the heart and increasing myocardial oxygen demand or provoking fatal cardiac arrhythmias. Levosimendan also opens ATP-sensitive potassium channels, causing peripheral arterial and venous dilatation, and increasing coronary flow reserve. When it is given as a short-term therapy, levosimendan enhances cardiac output, reduces systemic vascular resistance and lowers pulmonary capillary wedge pressure. Clinical outcomes were significantly reduced in decompensated or postmyocardial infarction heart failure patients who received levosimendan, compared with those on dobutamine or placebo. Recent investigations focusing on the anti-inflammatory and antiapoptotic actions of levosimendan in the failing heart indicate that improvement of cardiac contractile performance is closely related with the drug-induced reduction of circulating pro-inflammatory cytokines and apoptosis inducers. The most common adverse effects of levosimendan treatment are hypotension and headache. Overall, levosimendan represents an effective and safe option for the treatment of decompensated heart failure patients.