Levosimendan: Implications for Clinicians

The Role of Perioperative Levosimendan in Patients with Reduced Ejection Fraction undergoing Cardiac surgery in Reducing Post-operative Hemodynamic Support

BACKGROUND: Acute perioperative left ventricular dysfunction is a major complication affecting patients subjected to cardiac surgery and is associated with increased mortality. Levosimendan as a “calcium sensitizers” with inodilator effect improves myocardial contractility by sensitizing troponin C to calcium without increasing myocardial oxygen consumption and without impairing relaxation and diastolic function. AIM: The aim of this study was to evaluate the effect of perioperative levosimendan compared to the conventional management used in the patient with poor left ventricular function undergoing cardiac surgery to reduce the need of post-operative pharmacological and mechanical circulatory support. METHODS: It is prospective observational studies were patients undergoing cardiac surgery divided into two groups of 25 patients each. The first group received conventional management while the other group received levosimendan additionally duration and type of post-operative pharmacological support, duration of mechanical ventilation, durations of ICU and hospital stays, and major outcomes, and data about the need of mechanical support were collected. RESULTS: In the levosimendan, fewer patients required vasoactive agents post-surgery (Noradrenaline) compared to the conventional group, yet the use of inotropic support (adrenaline) in the 2nd day and the need of mechanical circulatory support was equal in both groups. The mortality was equal in both groups. CONCLUSION: Perioperative levosimendan may reduce the need of vasoactive agents postoperatively, but it does not reduce the need of inotropic nor mechanical support.

Cardiac Ischemia On-a-Chip: Antiarrhythmic Effect of Levosimendan on Ischemic Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Ischemic heart disease (IHD) is one of the leading causes of mortality worldwide. Preserving functionality and preventing arrhythmias of the heart are key principles in the management of patients with IHD. Levosimendan, a unique calcium (Ca2+) enhancer with inotropic activity, has been introduced into clinical usage for heart failure treatment. Human-induced pluripotent cell-derived cardiomyocytes (hiPSC-CMs) offer an opportunity to better understand the pathophysiological mechanisms of the disease as well as to serve as a platform for drug screening. Here, we developed an in vitro IHD model using hiPSC-CMs in hypoxic conditions and defined the effects of the subsequent hypoxic stress on CMs functionality. Furthermore, the effect of levosimendan on hiPSC-CMs functionality was evaluated during and after hypoxic stress. The morphology, contractile, Ca2+-handling, and gene expression properties of hiPSC-CMs were investigated in response to hypoxia. Hypoxia resulted in significant cardiac arrhythmia and decreased Ca2+ transient amplitude. In addition, disorganization of sarcomere structure was observed after hypoxia induction. Interestingly, levosimendan presented significant antiarrhythmic properties, as the arrhythmia was abolished or markedly reduced with levosimendan treatment either during or after the hypoxic stress. Moreover, levosimendan presented significant protection from the sarcomere alterations induced by hypoxia. In conclusion, this chip model appears to be a suitable preclinical representation of IHD. With this hypoxia platform, detailed knowledge of the disease pathophysiology can be obtained. The antiarrhythmic effect of levosimendan was clearly observed, suggesting a possible new clinical use for the drug.

Effect of Levosimendan Compared to Conventional Inotropic Agents on Hemodynamics and Outcome in Patient with Poor LV Function Undergoing Cardiac Surgery

BACKGROUND

Patients undergoing heart surgery involving cardiopulmonary bypass (CPB) experience global myocardial ischemia with subsequent reperfusion which, despite cardioplegic protection, may result in different degrees of transient ventricular dysfunction. Levosimendan is a "calcium sensitisers", it improves myocardial contractility by sensitising troponin C to calcium without increasing myocardial oxygen consumption and without impairing relaxation and diastolic function.

AIM

To evaluate the adding effect of a calcium sensitiser (levosimendan) compared to the conventional inotropic and vasoactive agent used in the patient with poor left ventricular function undergoing cardiac surgery on different measured hemodynamic variables and the effect on the outcome.

METHODS

It is prospective observational studies were patients were divided into 2 groups of 30 patients each. The first Group received conventional inotropic and vasoactive treatment at different doses, while the other group received levosimendan additionally at a loading dose of 6-12mic/kg according to mean arterial pressure over 0.5 hr followed by 24 hrs infusion at 0.05 to 0.2 mic/kg/min. Hemodynamic data were collected at the end and 30 minutes after CPB, after that at 6, 12, 24, and 36 hours post CPB. Mean arterial pressure (MAP), central venous pressure (CVP), heart rate (HR), mixed venous saturation (Svo2), and base deficit (BD) were measured.

RESULTS

Levosimendan had significantly improved postoperative hemodynamic values as in the mixed venous pressure at different times postoperative (p < 0.05), also the base deficit at different times postoperative (p < 0.05), while there was a significant reduction in systemic vascular resistance as decreased mean arterial pressure in levosimendan group compared to conventional group at 6hrs postoperative mean 77.50 ± 10.81 vs 83.73 ± 10.81 with (p = 0.029), and at 12 hrs postoperative mean 77.37 ± 10.10vs 84.23 ± 13.81 with (p = 0.032), and there was no significant difference in heart rate at different times postoperative between both groups (p > 0.05), while there was no significant effect on mortality between both groups (p = 0.781).

CONCLUSION

Levosimendan had improved hemodynamic parameters significantly with no effect on mortality compared to conventional inotropic agents in a patient with poor left ventricular function undergoing cardiac surgery.

Haemodynamic effects of levosimendan in advanced but stable chronic heart failure

AIMS

Levosimendan improves haemodynamics in acute decompensated heart failure (HF). However, it is increasingly used for repetitive or intermittent infusions in advanced but stable chronic HF, without clear indication, selection criteria, or effect. We tested the hypotheses that (1) levosimendan improves haemodynamics in stable chronic HF and (2) that the response is dependent on baseline clinical and haemodynamic factors.

METHODS AND RESULTS

Twenty-three patients [median age 56 (49-64) years, four (17%) women] with stable New York Heart Association (NYHA) III and IV HF received a single 24 h levosimendan infusion. Non-invasive haemodynamics (inert gas re-breathing technique), estimated glomerular filtration rate, and N-terminal pro-brain natriuretic peptide were assessed before and after infusion. Levosimendan had the following effects (median change): a significant increase in cardiac output (+9.8 ± 21.6%; P = 0.026) and decrease in N-terminal pro-brain natriuretic peptide (-28.1 ± 16.3%, P < 0.001), estimated total peripheral resistance (-16.9 ± 18.3%, P = 0.005), and mean arterial pressure (-5.9 ± 8.2%, P = 0.007), but no change in estimated glomerular filtration rate (+0.89 ± 14.0%, P = 0.955). There were no significant associations between baseline clinical and/or haemodynamic factors and the levosimendan effect on cardiac output.

CONCLUSIONS

Levosimendan was associated with improved haemodynamics in patients with stable chronic HF, but we could not identify any predictors of the magnitude of haemodynamic response.

Peri-operative Levosimendan in Patients Undergoing Cardiac Surgery: An Overview of the Evidence

Levosimendan, a calcium sensitiser, has recently emerged as a valuable agent in the peri-operative management of cardiac surgery patients. Levosimendan is a calcium-sensitising ionodilator. By binding to cardiac troponin C and reducing its calcium-binding co-efficient, it enhances myofilament responsiveness to calcium and thus enhances myocardial contractility without increasing oxygen demand. Current evidence suggests that levosimendan enhances cardiac function after cardiopulmonary bypass in patients with both normal and reduced left ventricular function. In addition to being used as post-operative rescue therapy for low cardiac output syndrome, a pre-operative levosimendan infusion in high risk patients with poor cardiac function may reduce inotropic requirements, the need for mechanical support, the duration of intensive care admissions as well as post-operative mortality. Indeed, it is these higher-risk patients who may experience a greater degree of benefit. Larger, multicentre randomised trials in cardiac surgery will help to elucidate the full potential of this agent.

One problem two issues! Left ventricular systolic and diastolic dysfunction in aortic stenosis

Reports suggested that immediate post-aortic valve replacement (AVR); left ventricular (LV) dysfunction may be an important risk for morbidity and mortality in patients requiring positive inotropic support. Several factors have been identified as significant prognostic factors i.e., LV systolic dysfunction, LV diastolic dysfunction (LV-DD), heart failure and myocardial infarction (MI). Specific to pathophysiological changes associated with AS, markers of systolic LV function (e.g., LVEF) have been extensively studied in management, yet only a few studies have analysed the association between LV-DD and immediate post-operative LV dysfunction This review brings together the current body of evidence on this issue.

Effectiveness of prophylactic levosimendan in high-risk valve surgery patients

Background

Levosimendan has anti-ischaemic effects, improves myocardial contractility and increases systemic, pulmonary and coronary vasodilatation. These properties suggest potential advantages in high-risk cardiac valve surgery patients where cardioprotection would be valuable. The present study investigated the peri-operative haemodynamic effects of prophylactic levosimendan infusion in cardiac valve surgery patients with low ejection fraction and/or severe pulmonary arterial hypertension.

Methods

Between May 2006 and July 2007, 20 consecutive patients with severe pulmonary arterial hypertension (systolic pulmonary artery pressure ≥ 60 mmHg) and/or low ejection fraction (< 50%) who underwent valve surgery in our clinic were included in the study and randomised into two groups. Levosimendan was administered to 10 patients in group I and not to the 10 patients in the control group. Cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and mean pulmonary artery pressure (MPAP) were recorded for each patient preoperatively and for 24 hours following the operation.

Results

CO and CI values were higher in the levosimendan group during the study period (p < 0.05). MPAP and PVR values were significantly lower in the levosimendan group for the 24-hour period (p < 0.05) and SVR values were significantly lower after 24 hours in both groups. When clinical results were considered, no difference in favour of levosimendan was detected regarding the mortality and morbidity rates between the groups.

Conclusion

Levosimendan improved the haemodynamics in cardiac valve surgery patients with low ejection fraction and/or severe pulmonary arterial hypertension, and facilitated weaning from cardiopulmonary bypass in such high-risk patients when started as a prophylactic agent.

Effects of levosimendan on glomerular filtration rate, renal blood flow, and renal oxygenation after cardiac surgery with cardiopulmonary bypass: a randomized placebo-controlled study

OBJECTIVES

Acute kidney injury develops in a large proportion of patients after cardiac surgery because of the low cardiac output syndrome. The inodilator levosimendan increases cardiac output after cardiac surgery with cardiopulmonary bypass, but a detailed analysis of its effects on renal perfusion, glomerular filtration, and renal oxygenation in this group of patients is lacking. We therefore evaluated the effects of levosimendan on renal blood flow, glomerular filtration rate, renal oxygen consumption, and renal oxygen demand/supply relationship, i.e., renal oxygen extraction, early after cardiac surgery with cardiopulmonary bypass.

DESIGN

Prospective, placebo-controlled, and randomized trial.

SETTING

Cardiothoracic ICU of a tertiary center.

PATIENTS

Postcardiac surgery patients (n=30).

INTERVENTIONS

The patients were randomized to receive levosimendan, 0.1 µg/kg/min after a loading dose of 12 µg/kg (n=15), or placebo (n=15).

MEASUREMENTS AND MAIN RESULTS

The experimental procedure started 4-6 hours after surgery in the ICU during propofol sedation and mechanical ventilation. Systemic hemodynamic were evaluated by a pulmonary artery thermodilution catheter. Renal blood flow and glomerular filtration rate were measured by the renal vein retrograde thermodilution technique and by renal extraction of Cr-EDTA, respectively. Central venous pressure was kept constant by colloid/crystalloid infusion. Compared to placebo, levosimendan increased cardiac index (22%), stroke volume index (15%), and heart rate (7%) and decreased systemic vascular resistance index (21%), whereas mean arterial pressure was not affected. Levosimendan induced significant increases in renal blood flow (12%, p<0.05) and glomerular filtration rate (21%, p<0.05), decreased renal vascular resistance (18%, p<0.05) but caused no significant changes in filtration fraction, renal oxygen consumption, or renal oxygen extraction, compared to placebo.

CONCLUSIONS

After cardiac surgery with cardiopulmonary bypass, levosimendan induces a vasodilation, preferentially of preglomerular resistance vessels, increasing both renal blood flow and glomerular filtration rate without jeopardizing renal oxygenation. Due to its pharmacodynamic profile, levosimendan might be an interesting alternative for treatment of postoperative heart failure complicated by acute kidney injury in postcardiac surgery patients.

Levosimendan Use Decreases Atrial Fibrillation in Patients after Coronary Artery Bypass Grafting: A Pilot Study

Background: Atrial fibrillation (AF) often occurs after coronary artery bypass grafting (CABG) and can result in increased morbidity and mortality due to complications. In the present study, our goal was to investigate whether the use of levosimendan can reduce the frequency of AF after coronary artery bypass grafting in patients with poor left ventricle function. Material and Methods: To investigate the effectiveness of levosimendan in the prophylaxis of AF, we conducted a prospective, randomized, placebo-controlled clinical study on 200 consecutive patients in whom we performed elective CABG operations. Baseline characteristics were similar in both groups. A control group of 100 patients were treated with placebo (500 mL saline solution), whereas the levosimendan group (n = 100 patients) was treated with levosimendan. High-sensitivity C-reactive protein, cardiac troponin, and creatine kinase–MB levels were measured before surgery and 5 days postoperatively. Results: AF occurred in 12% of the levosimendan group and 36% of the control group. The occurrence of AF was significantly lower in the levosimendan group (P < 0.05). The duration of AF in the levosimendan group was significantly shorter than that in the control group (4.83 ± 1.12 and 6.50 ± 1.55 hours, respectively; P = 0.028). Our research showed that C-reactive protein was higher postoperatively in the control group than in the levosimendan group (P < 0.05). Conclusions: The incidence of postoperative AF in the levosimendan group was reduced significantly in patients with poor left ventricle function after CABG operations.

Update on management strategies for separation from cardiopulmonary bypass

PURPOSE OF REVIEW

To update the reader about clinical management strategies for separation from cardiopulmonary bypass. A number of new drugs are being introduced in clinical practice, with significant utility in operative patient management. Further, there is increased routine use of complex devices to achieve separation from or avoidance of cardiopulmonary bypass.

RECENT FINDINGS

Selected medical and device strategies from the most recent literature will be discussed. First, the rationale for selected innovative agents to achieve myocardial performance is reviewed in four perioperative settings: agents for the management of myocardial dysfunction, vasomotor dysfunction, pulmonary hypertension, and right ventricular failure. Second is an evaluation of less commonly considered aspects of mechanical device use in the context of failure to wean from cardiopulmonary bypass or use to avoid cardiopulmonary bypass. Three devices will be discussed: intra-aortic balloon pump, ventricular assist devices, and extracorporeal membrane oxygenation.

SUMMARY

As our pharmacological and technological armamentarium improve, our population ages and procedures are attempted on patients with increasing co-morbid conditions, it will be important to both utilize newer pharmacological agents and consider innovative uses for device implementation to achieve optimal perioperative outcomes.

Effects of levosimendan/furosemide infusion on plasma brain natriuretic peptide, echocardiographic parameters and cardiac output in end-stage heart failure patients

BACKGROUND

Acute decompensation heart failure (ADHF) remains a cause of hospitalization in patients with end-stage congestive HF. The administration of levosimendan in comparison with a standard therapy in CHF patients admitted for ADHF was analysed.

MATERIAL/METHODS

Consecutive patients admitted for ADHF (NYHA class III-IV) were treated with levosimendan infusion 0.1 µg/kg/min or with furosemide infusion 100-160 mg per day for 48 hours (control group). All subjects underwent determination of brain natriuretic peptide (BNP), non-invasive cardiac output (CO), and echocardiogram at baseline, at the end of therapy and 1 week after therapy.

RESULTS

Seven patients admitted for 20 treatments in 16 months (age 66 years; mean admission/year 5.4) were treated with levosimendan and compared with 7 patients admitted for 15 treatments (age 69.1 years; mean admission/year 6.1). At the end of levosimendan therapy, BNP decreased (from 679.7 ± 512.1 pg/ml to 554.2 ± 407.6 pg/ml p = 0.03), and 6 MWT and LVEF improved (from 217.6 ± 97.7 m to 372.2 ± 90.4 m p = 0.0001; from 22.8 ± 9.1% to 25.4 ± 9.8% p = 0.05). Deceleration time, E/A, E/E', TAPSE, pulmonary pressure and CO did not change significantly after levosimendan therapy and after 1 week. At follow-up, only 6-min WT and NYHA class showed a significant improvement (p = 0.0001, p = 0.001 respectively). The furosemide infusion reduced NYHA class and body weight (from 3.4 ± 0.6 to 2.3 ± 0.5 p = 0.001; from 77.5 ± 8.6 kg to 76 ± 6.6 kg p = 0.04), but impaired renal function (clearances from 56.3 ± 21.9 ml/min to 41.2 ± 10.1 ml/min p = 0.04).

CONCLUSIONS

Treating end-stage CHF patients with levosimendan improved BNP and LVEF, but this effect disappeared after 1 week. The amelioration of 6 MWT and NYHA class lasted longer after levosimendan infusion.

Improvement in Doppler alternans in patients with severe heart failure: Levosimendan versus dobutamin

Mechanical alternans, an ominous sign of terminal systolic heart failure, could be indirectly shown by Doppler analysis. On the other hand, Levosimendan, a novel agent, improves contractility in patients with HF. We searched the effect of L versus dobutamin onto Doppler alternans in patients with systolic HF. We found that Levosimendan improves beat-to-beat alteration in patients with systolic HF, demonstrated by pulsed Doppler compared to dobutamin.

Effects of Levosimendan on Quality of Life and Emotional Stress in Advanced Heart Failure Patients

AIM

Levosimendan improves central hemodynamics and symptoms in acutely decompensated chronic heart failure (CHF) patients. However, its effects on quality of life, emotional stress and functional capacity of patients with advanced CHF have not been properly investigated.

METHODS AND RESULTS

Sixty-three advanced CHF patients (NYHA III-IV, LVEF<30%) were randomized (2:1) to receive either a 24-h levosimendan infusion of 0.1 mug/kg/min or placebo. Questionnaires addressing quality of life [Kansas City Cardiomyopathy Questionnaire (KCCQ), functional and overall, Duke's Activity Status Index (DASI)] and emotional stress [Zung self-rating depression scale (SDS), Beck Depression Inventory (BDI)], as well as plasma BNP and 6-min walking distance (6MWT as a marker of exercise capacity) were assessed before treatment and at hospital discharge. A significant improvement in NYHA class (2.1 +/- 0.7 from 3.3 +/- 0.7, p < 0.01), 6 MWT (305 +/- 152 from 215 +/- 142 m, p < 0.01) and plasma BNP (598 +/- 398 from 1,078 +/- 756 pg/ml, p < 0.01) was observed post-treatment only in levosimendan-treated group. KCCQ functional (45 +/- 19 from 35 +/- 17%, p < 0.05) and overall (34 +/- 13 from 28 +/- 11%, p < 0.05), DASI (26 +/- 13 from 22 +/- 12, p < 0.05), Zung SDS (38 +/- 12 from 42 +/- 13, p < 0.01) and BDI (11 +/- 6 from 14 +/- 8, p < 0.05) scores also improved in levosimendan-treated patients, while remained unchanged in the placebo group. The hospital length stay was shorter in levosimendan group compared to placebo (3.2 +/- 1.7 versus 5.8 +/- 2.1 days, p < 0.01). Levosimendan-induced BNP reduction was significantly correlated with concomitant increase in 6MWT (r = 0.643, p < 0.001) as well as with the decrease of BDI (r = 0.30, p < 0.05) and Zung SDS (r = 0.25, p = 0.05).

CONCLUSION

Levosimendan seems to have a beneficial effect on quality of life, physical activity and emotional stress in advanced CHF patients, reducing concurrently hospitalization length.

Review of current and investigational pharmacologic agents for acute heart failure syndromes

Acute heart failure syndromes (AHFS) are a major public health problem and present a therapeutic challenge to clinicians. Commonly used agents in the treatment of AHFS include diuretics, vasodilators (eg, nitroglycerin, nitroprusside, nesiritide), and inotropes (eg, dobutamine, dopamine, milrinone). Patients admitted to hospital with AHFS and low cardiac output state (AHFS/LO) represent a subgroup with very high inhospital and postdischarge mortality rates. Most of these patients require intravenous inotropic therapy. However, the use of current intravenous inotropes has been associated with risk for hypotension, atrial and ventricular arrhythmias, and possibly increased postdischarge mortality, particularly in those with coronary artery disease. Consequently, there is an unmet need for new agents to safely improve cardiac performance (contractility and/or active relaxation) in this patient population. This article reviews a selection of current and investigational agents for the treatment of AHFS, with a main focus on the high-risk patient population with AHFS/LO.

Effect of levosimendan on ventricular arrhythmias and prognostic autonomic indexes in patients with decompensated advanced heart failure secondary to ischemic or dilated cardiomyopathy

Positive inotropes used for the treatment of heart failure have been arrhythmogenic. Levosimendan is a novel calcium sensitizer with vasodilating properties and a complex mechanism of action. Its effect on ventricular arrhythmias and 24-hour Holter electrocardiographically derived prognostic autonomic nervous system-related markers, because it occurs in parallel with changes in cardiac function and neurohormonal response, has not been systematically assessed. Forty-five patients (mean age 65 +/- 1.3 years) with heart failure refractory to conventional therapy and a mean ejection fraction of 23 +/- 1.2%, randomized to levosimendan or placebo, were studied. After Holter electrocardiographic recording, 1 drug was infused for 24 hours (levosimendan at a dose of 0.1 mug/kg/min). During this period, another Holter recording was performed to assess changes in ventricular arrhythmogenesis, 24-hour heart rate variability indexes, QTc, QT variability, and QT/RR slope. Clinical evaluation, echocardiography, and B-type natriuretic peptide measurements were performed at baseline and after treatment. After levosimendan, clinical and echocardiographic improvement was observed, associated with beneficial neurohormonal modulation (mean B-type natriuretic peptide level after levosimendan 668 +/- 108 vs 1,009 +/- 122 pg/ml at baseline, p <0.05). Episodes of nonsustained ventricular tachycardia increased with levosimendan (21.9 +/- 9.6 vs 3.0 +/- 1.2, p <0.05). Levosimendan and placebo exerted a neutral effect on all autonomic markers assessed. In conclusion, levosimendan at low doses increases nonsustained ventricular arrhythmias, without affecting Holter-derived, prognostically significant autonomic markers. At the same time, it is associated with improvements in cardiac function and neurohormonal response. These findings may have important clinical and prognostic implications.

Effects of serial levosimendan infusions on left ventricular performance and plasma biomarkers of myocardial injury and neurohormonal and immune activation in patients with advanced heart failure

BACKGROUND

Levosimendan is a novel inodilator that improves central haemodynamics and symptoms of patients with decompensated chronic heart failure. The role, however, of repeated levosimendan infusions in the management of these patients has not yet been properly assessed.

PURPOSE

This randomised placebo-controlled trial investigated the effects of serial levosimendan infusions on cardiac geometry and function, and on biomarkers of myocardial injury and neurohormonal and immune activation (troponin T, N-terminal B-type natriuretic pro-peptide (NT-proBNP), C reactive protein (CRP) and interleukin (IL) 6) in patients with advanced heart failure.

METHODS

25 patients with decompensated chronic heart failure were randomised (2:1) to receive five serial 24-h infusions (every 3 weeks) of either levosimendan (n = 17) or placebo (n = 8), and were evaluated echocardiographically and biochemically before and after each drug infusion and 30 days after the final infusion.

RESULTS

Following treatment, cardiac end-systolic and end-diastolic dimension and volume indices were significantly reduced only in the levosimendan-treated patients (p<0.01). A significant decrease in NT-proBNP (p<0.01), high-sensitivity CRP (p<0.01) and plasma IL6 (p = 0.05) was also observed in the levosimendan group, whereas these markers remained unchanged in the placebo group; similar changes were observed after each drug infusion. Although the number of patients with a positive troponin T (>or=0.01 ng/ml) was not different between the two groups at baseline, it was significantly higher in the placebo-treated group during the final evaluation (p<0.05).

CONCLUSION

Serial levosimendan treatments improved left ventricular performance and modulated neurohormonal and immune activation beneficially in patients with advanced heart failure, without increasing myocardial injury.

Cardiogenic shock after primary percutaneous coronary intervention: Effects of levosimendan compared with dobutamine on haemodynamics

BACKGROUND

Levosimendan is a new calcium sensitizer with positive inotropic properties. Cardiac power output (CPO) has been shown to be instrumental in the diagnosis of cardiogenic shock (CS) and is an important determinant of outcomes.

AIMS

To evaluate the haemodynamic effects of levosimendan compared to dobutamine in acute myocardial infarction (AMI) patients revascularised by primary percutaneous coronary intervention (PCI), who developed CS.

METHODS AND RESULTS

Twenty two consecutive AMI patients revascularised by PCI, who developed CS, were randomly assigned to levosimendan (24 microg kg(-1) bolus plus 24-h continuous infusion 0,1 microg kg(-1) min(-1)) or dobutamine (initial dose 5 microg kg(-1) min(-1), with a maximum dose adjustment in order to reach the desired haemodynamic effect). Evaluations were performed from baseline to 30 h. The primary end-point was an increase > or =30% in CPO, after 24 h of therapy. The baseline clinical and haemodynamic characteristics were similar in both groups. Levosimendan had a consistently better effect on CPO than dobutamine, while the decrease in PCWP was similar.

CONCLUSION

The primary objective of our study was achieved better by the end of the 24 h infusion of levosimendan than by dobutamine.

Pharmacologic treatment of heart failure due to ventricular dysfunction by myocardial stunning: potential role of levosimendan

The treatment of heart failure continues to pose a real challenge for clinicians. This condition is sometimes reversible and therapy should therefore pursue this outcome. In the context of coronary ischemic syndromes, myocardial stunning can cause heart failure and even cardiogenic shock, with important prognostic repercussions. Myocardial stunning is mainly due to calcium overload in the cytosol of myocardial cells, the loss of myofilaments and their reduced sensitivity to calcium. Enhanced immune activation with inflammatory phenomena also plays an important role in the pathophysiology of cardiac dysfunction. Increasing evidence has shown that the myocardial ATP-dependent potassium channel (K(ATP)) plays an important role in many myocardial cell functions and that it is involved in ischemia-reperfusion injury and myocardial stunning. K(ATP) is thus considered a therapeutic target in this setting. Currently used inotropic drugs improve contractility by increasing intracellular concentrations of free calcium, but they increase myocardial consumption of energy and even produce arrhythmia; therefore, in this clinical context, they do not seem to be 'pathophysiologically correct' drugs. Levosimendan, a new calcium-sensitizing agent, increases contractility by enhancing the sensitivity of myofilaments to calcium by binding to the C cardiac troponin in cardiac muscle in a calcium-dependent way. Levosimendan also exerts a coronary and systemic vasodilatory effect through its K(ATP) channel-opening properties and may exert other cardioprotective actions through this mechanism. Levosimendan produces positive hemodynamic effects without increasing myocardial oxygen demand or causing arrhythmias. Intravenous levosimendan is generally well tolerated and has been approved by several European countries, and recently recommended in European Society of Cardiology guidelines, as inotropic therapy for the short-term treatment of acute severe decompensated heart failure in adults. Randomized, double-blind trials have shown that levosimendan is not only more clinically and hemodynamically effective but also that it significantly reduces morbidity and mortality when compared with dobutamine or placebo. Clinical trials addressing the use and efficacy of intravenous levosimendan in acute heart failure in patients with systolic dysfunction or cardiogenic shock due to myocardial stunning are scarce. Beneficial effects on myocardial contractility in patients with myocardial stunning have only been shown in small clinical trials. A positive experience with levosimendan in a small series of patients with cardiogenic shock complicating ST-elevation myocardial infarction suggests that the use of this drug in cardiogenic shock should be further evaluated.

Advances in cardiac intensive care

PURPOSE OF REVIEW

As surgical survival in children with congenital heart disease, particularly those with univentricular hearts, has improved in recent years, focus has shifted to reducing the morbidity of congenital cardiac malformations and their treatment. This review will focus on emerging therapies aimed at reducing these morbidities in the intensive care unit.

RECENT FINDINGS

A protracted stay in the intensive care unit after cardiac surgery is a risk factor for developing various morbidities. Therapies or interventions that may hasten postoperative recovery and minimize the length of stay are thus important to evaluate. Fluid overload, renal dysfunction, low cardiac output and neurological dysfunction remain major contributors to morbidity after cardiac surgery. In addition, the treatment of these adverse states can potentially compound the injury.

SUMMARY

The reduction in morbidity after cardiac surgery remains challenging. Recent insights have allowed us to recognize the impact of factors beyond the intraoperative period as significant contributors to morbidity. As our field continues to evolve, future studies should focus on emerging technologies and therapies that facilitate the prevention of physiological states that compound congenital morbidities.

Pharmacological Mechanisms Contributing to the Clinical Efficacy of Levosimendan

Acute decompensation of chronic heart failure is a direct life-threatening situation with short-term mortality approaching 30%. A number of maladaptive changes are amplified within the cardiovascular system during the progression of chronic heart failure that makes the decompensation phase difficult to handle. Levosimendan is a new Ca2+-sensitizer for the treatment of acutely decompensated heart failure that has proved to be effective during the decompensation of chronic heart failure and acute myocardial infarction. Levosimendan differs from other cardiotonic agents that are used for acute heart failure in that it utilizes a unique dual mechanism of action: Ca2+-sensitization through binding to troponin C in the myocardium, and the opening of ATP-sensitive K+ channels in vascular smooth muscle. In general, these mechanisms evoke positive inotropy and vasodilation. Clinical studies suggested long-term benefits on mortality following short-term administration. It may, therefore, be inferred that levosimendan has additional effects on the cardiovascular system that are responsible for the prolongation of survival. Results of preclinical and clinical investigations suggest that the combination of levosimendan-induced cardiac and vascular changes has favorable effects on the coronary, pulmonary and peripheral circulations. Redistribution of the circulating blood offers an improved hemodynamic context for the development of a positive inotropic effect through Ca2+-sensitization of the contractile filaments, without a proportionate increase in myocardial oxygen consumption or the development of arrhythmias. Activation of ATP-sensitive K+ channels, both on sarcolemma and mitochondria, may protect against myocardial ischemia, and decreased levels of cytokines may prevent the development of further myocardial remodeling. Collectively, these effects of levosimendan shift the disturbed cardiovascular parameters towards normalization, thereby halting the perpetuation of the vicious cycle of heart failure progression. This may contribute to stabilization of the circulation and improved life expectancy of patients with chronic heart failure.

Levosimendan or Milrinone in the Type 2 Diabetic Patient With Low Ejection Fraction Undergoing Elective Coronary Artery Surgery

OBJECTIVES

The purpose of this study was to compare the hemodynamic profiles and the postoperative insulin requirements in 2 groups of type 2 diabetic patients with depressed myocardial function who underwent elective surgery for coronary artery disease and who received levosimendan or milrinone for postcardiopulmonary bypass low-output syndrome.

DESIGN

Randomized controlled trial.

SETTING

The Chest Diseases Hospital, Safat, Kuwait.

PARTICIPANTS

Type 2 diabetic patients undergoing elective surgery for coronary artery disease.

INTERVENTIONS

Fourteen patients and 16 patients received levosimendan and milrinone infusions, respectively, for treatment of the low-output syndrome.

MEASUREMENTS AND MAIN RESULTS

The hemodynamic, mixed venous oxygen saturation, oxygen extraction ratios, arterial lactate concentrations, and postoperative insulin infusion rates were serially documented for the first 48 hours after the diagnosis. The cardiac index and mixed venous oxygen saturation were significantly higher in the levosimendan group. The pulmonary capillary wedge pressure, systemic vascular resistance, and oxygen extraction ratios were significantly higher in the milrinone treatment group. The insulin requirements were similar for both of the treatment groups.

CONCLUSIONS

Levosimendan was more efficient than milrinone for treating the hemodynamic manifestations of the postcardiopulmonary bypass low-output syndrome. However, all the values in the milrinone treatment group were normalized. In this small population, both treatment groups had similar postoperative insulin requirements.

Levosimendan in Cardiac Surgery: Current Best Available Evidence

Recent upsurge in referral of patients with high perioperative risk or compromised left ventricular function for cardiac surgery has lead to an increasing use of pharmacologic support in the form of vasodilator and inotropic therapy to achieve improvement of tissue perfusion in the perioperative period or to support weaning from cardiopulmonary bypass. Traditionally, perioperatively used inotropic agents, epinephrine, dobutamine, and milrinone, are limited by significant increases in myocardial oxygen consumption, proarrhythmia, or neurohormonal activation. Levosimendan, a new inodilator for the treatment of decompensated heart failure, has also shown promise in elective therapy of cardiac surgical patients with high perioperative risk or compromised left ventricular function, as well as in rescue therapy of patients with difficult weaning from cardiopulmonary bypass. This review article briefly discusses the pharmacology of levosimendan and evaluates current best available evidence to assess the safety and efficacy of levosimendan usage in cardiac surgery.

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.

Levosimendan: a novel inotropic agent for treatment of acute, decompensated heart failure

OBJECTIVE

To review the literature on a novel calcium sensitizer, levosimendan.

DATA SOURCES

Articles were identified through searches of MEDLINE (1966-June 2005), International Pharmaceutical Abstracts (1970-June 2005), and EMBASE (1992-June 2005) using the key words levosimendan, simendan, calcium sensitizer, calcium sensitiser, and congestive heart failure.

STUDY SELECTION AND DATA EXTRACTION

Clinical trials and pharmacokinetic studies evaluating the safety and efficacy of levosimendan were selected.

DATA SYNTHESIS

Levosimendan 6-24 mug/kg intravenous bolus followed by a 24-hour continuous infusion of 0.05-0.2 microg/kg/min improved cardiac output and reduced pulmonary capillary wedge pressure in a dose-dependent manner. Dose-ranging and randomized clinical trials have demonstrated improvement in symptoms and hemodynamics and short-term survival outcomes in the treatment of acute, decompensated heart failure. Clinical trials evaluating retrospective mortality data and combined endpoints (mortality, rehospitalization) have demonstrated better outcomes with levosimendan compared with dobutamine. The incidence of hypotension with levosimendan is not significantly different than with dobutamine, but there is a dose-related increase in heart rate.

CONCLUSIONS

Levosimendan is useful in moderate to severe low-output heart failure in patients who have failed to respond to diuretics and vasodilators. Based on current studies, levosimendan appears to be a safe alternative to dobutamine for treatment of acute, decompensated heart failure. Prospective clinical trials are needed to confirm the effect of levosimendan on long-term survival and its role in heart failure in the setting of myocardial infarction.

Effects of levosimendan on markers of left ventricular diastolic function and neurohormonal activation in patients with advanced heart failure

In this randomized, placebo-controlled study, it was found that a 24-hour levosimendan infusion improves echocardiographic markers of abnormal left ventricular diastolic function (transmitral flow patterns and mitral annulus velocities, as assessed by transthoracic pulse-wave Doppler and tissue Doppler imaging, respectively) and reduces substances of excessive neurohormonal activation (plasma B-type natriuretic peptide and interleukin-6) in patients with advanced heart failure. Moreover, levosimendan-treated patients had fewer events and longer progression-free survival during a 5-month follow-up compared with those who received placebo. Thus, levosimendan seems to be effective in improving left ventricular diastolic function and reducing neurohormonal activation in patients with severe heart failure.