Levosimendan: A New Therapeutic Option in the Treatment of Primary Graft Dysfunction After Heart Transplantation

Perioperative Management of Heart Transplantation: A Clinical Review

In this clinical review, the authors summarize the perioperative management of heart transplant patients with a focus on hemodynamics, immunosuppressive strategies, hemostasis and hemorrage, and the prevention and treatment of infectious complications.

Primary Graft Dysfunction after Heart Transplantation - Unravelling the Enigma

Primary graft dysfunction (PGD) remains the main cause of early mortality following heart transplantation despite several advances in donor preservation techniques and therapeutic strategies for PGD. With that aim of establishing the aetiopathogenesis of PGD and the preferred management strategies, the new consensus definition has paved the way for multiple contemporaneous studies to be undertaken and accurately compared. This review aims to provide a broad-based understanding of the pathophysiology, clinical presentation and management of PGD.

Levosimendan for Treatment of Primary Graft Dysfunction After Heart Transplantation: Optimal Timing of Application

OBJECTIVES

Primary graft dysfunction remains a serious problem after heart transplant. Pharmacological treatment with the calcium sensitizer levosimendan may be an additive treatment for primary graft dysfunction.

MATERIALS AND METHODS

Patients undergoing heart transplant between 2010 and 2020 were retrospectively reviewed and divided depending on postoperative treatment with (n = 41) or without (n = 109) levosimendan. Recipients who received levosi mendan were further divided with regard to timing of levosimendan application (early group: started ≤48 hours posttransplant [n = 23]; late group: started >48 hours posttransplant [n = 18]).

RESULTS

Patients who received levosimendan treatment displayed a remarkable incidence (87.8%) of postoperative primary graft dysfunction with need for venoarterial extracorporeal membrane oxygenation and therefore often presented with perioperative morbidity. Patient with early application of levosimendan showed significantly decreased duration of venoarterial extracorporeal membrane oxygenation support (5.1 ± 3.5 days vs 12.6 ± 9.3 days in those with late application; P < .01) and decreased mortality during venoarterial extracorporeal membrane oxygenation support (0.0% vs 33.3% in early vs late group; P < .01). In addition, compared with patients with late levosimendan application, patients with early application needed fewer blood transfusions (P < .05), had shorter ventilation times (279 ± 235 vs 428 ± 293 h; P = .03), and showed a trend of reduced incidence of postoperative renal failure (69.6% vs 94.4%; P = .06). Moreover, survival analyses indicated an increased survival for patients with early start of levosimendan therapy within the first 48 hours after heart transplant (P = .09).

CONCLUSIONS

Pharmacotherapy with levosimendan may be a promising additive in the treatment of primary graft dysfunction after heart transplant. With administration of levosimendan within the first 48 hours posttransplant, rates of successful weaning from venoarterial extracorporeal membrane oxygenation and outcomes after heart transplant were shown to increase.

Primary graft dysfunction after heart transplantation: a thorn amongst the roses

Primary graft dysfunction (PGD) remains the leading cause of early mortality post-heart transplantation. Despite improvements in mechanical circulatory support and critical care measures, the rate of PGD remains significant. A recent consensus statement by the International Society of Heart and Lung Transplantation (ISHLT) has formulated a definition for PGD. Five years on, we look at current concepts and future directions of PGD in the current era of transplantation.

Early Graft Dysfunction Following Heart Transplant: Prevention and Management

Heart transplant can be considered as the “gold standard” treatment for end-stage heart failure, with nearly 5.7 million adults in the United States carrying a diagnosis of heart failure. According to the International Society for Heart and Lung Transplantation registry, nearly 3300 orthotopic heart transplants were performed in 2016 in North America. In spite of significant improvements in overall perioperative care of heart transplant recipients for the past few decades, the risk of 30-day mortality remains 5% to 10%, primarily related to early failure of the allograft. Early graft dysfunction (EGD) occurs within 24 hours after transplant, manifesting as left ventricular dysfunction, right ventricular dysfunction, or biventricular dysfunction. EGD is further classified into primary and secondary graft dysfunction. This review focus on describing overall incidences of EGD, potential risk factors associated with EGD, perioperative preventive measures, and various management options.

Controversies in the Postoperative Management of the Critically Ill Heart Transplant Patient

Heart transplant recipients are susceptible to a number of complications in the immediate postoperative period. Despite advances in surgical techniques, mechanical circulatory support (MCS), and immunosuppression, evidence supporting optimal management strategies of the critically ill transplant patient is lacking on many fronts. This review identifies some of these controversies with the aim of stimulating further discussion and development into these gray areas.

Primary graft dysfunction in heart transplantation

PURPOSE OF REVIEW

Primary graft dysfunction (PGD) is common early postheart transplantation; however, use of standardized definitions remains inconsistent. This review focuses on understanding the incidence, classification, risk factors, and management of PGD.

RECENT FINDINGS

The incidence and mortality of PGD in heart transplant varies considerably in the published literature ranging from 1.0% to 31% and 3% to 75%, respectively. There is also considerable variation in management strategies with current data favoring early intervention.

SUMMARY

PGD in heart transplantation remains a challenging problem associated with significant mortality and morbidity. There is need for a consistent and accessible definition to better define associated risk factors and optimize management strategies.

Levosimendan as rescue therapy in low output syndrome after cardiac surgery: effects and predictors of outcome

Objectives

Calcium sensitizers have been shown to improve outcomes in patients with low cardiac output syndrome (LCOS) after cardiac surgery. We assessed the effects of levosimendan on LCOS in cardiac surgical patients to identify outcome predictors.

Methods

A total of 106 patients in whom LCOS persisted despite conventional therapy additionally received 0.1 µg/kg/min of levosimendan for 24 hours according to a defined treatment algorithm. Baseline and treatment data as well as hemodynamic and outcome parameters were compared between survivors and nonsurvivors, and a multivariate correlation and regression tree analysis was implemented.

Results

The ejection fraction significantly increased from 27% ± 4% to 38% ± 8% within 24 hours and to 45% ± 10% within 48 hours of starting levosimendan. These changes were accompanied by a significant increase in cardiac output from 5.2 ± 0.6 to 6.2 ± 0.7 L/min within 24 hours and significant dose reductions in vasopressors and inotropes. In contrast to nonsurvivors, survivors’ need for inotropic support decreased after the addition of levosimendan to the therapy.

Conclusion

In our patients, all of whom were treated according to the same algorithm, the response to levosimendan in terms of the post-levosimendan need for inotropes and vasopressors predicted survival.

The effects of levosimendan on renal function early after heart transplantation: results from a pilot randomized trial

BACKGROUND

We evaluated the effects of a levosimendan (LS)-based strategy compared with standard inotropic therapy on renal function in heart transplantation.

METHODS AND RESULTS

Using a randomized study design, 94 patients were assigned to LS-based therapy or standard inotropic support. At the time of transplantation, the groups did not differ in age, gender, heart failure etiology, hemodynamic profile, LVEF, or comorbidities. While there were no differences in serum creatinine (sCr) or eGFR between groups at baseline, patients in the LS group had a greater increase in their relative eGFR (62% vs. 12%, p = 0.002) and a lower incidence of acute kidney injury (AKI) (28% vs. 6%, p = 0.01) during the first post-transplant week. On logistic regression analysis, correlates of AKI were randomization to LS therapy (OR = 0.21 [0.09-0.62], p = 0.01), baseline renal dysfunction (OR = 3.9 [1.1-13.6], p = 0.032), and diabetes mellitus (OR = 4.2 [1.1-16.5], p = 0.038). However, LS was associated with a greater need for additional norepinephrine therapy (40 [85%] vs. 15 [31%], p < 0.001) and a trend toward longer intensive care unit stay (9.5 ± 9.0 d vs. 7.0 ± 6.0 d, p = 0.13).

CONCLUSIONS

In patients undergoing heart transplantation, levosimendan-based strategy may be associated with better renal function when compared to standard therapy.

Levosimendan in critical illness: a literature review

Levosimendan, the active enantiomer of simendan, is a calcium sensitizer developed for treatment of decompensated heart failure, exerts its effects independently of the beta adrenergic receptor and seems beneficial in cases of severe, intractable heart failure. Levosimendan is usually administered as 24-h infusion, with or without a loading dose, but dosing needs adjustment in patients with severe liver or renal dysfunction. Despite several promising reports, the role of levosimendan in critical illness has not been thoroughly evaluated. Available evidence suggests that levosimendan is a safe treatment option in critically ill patients and may reduce mortality from cardiac failure. However, data from well-designed randomized controlled trials in critically ill patients are needed to validate or refute these preliminary conclusions. This literature review is an attempt to synthesize available evidence on the role and possible benefits of levosimendan in critically ill patients with severe heart failure.

Preconditioning with levosimendan before implantation of left ventricular assist devices

In this retrospective study, we investigated the impact of preconditioning of the right ventricle with the calcium sensitizer levosimendan immediately before left ventricular assist device (LVAD) implantation on outcome and survival. Nine consecutive LVAD patients (seven suffering from dilative cardiomyopathy and two from ischemic cardiomyopathy) with echocardiographic and invasive evidence of right heart insufficiency received levosimendan with 0.1 μg/kg body weight/min for 24 h before implantation of the assist device (seven HeartWare and two Jarvik 2000). Administration of levosimendan was safe and had not to be discontinued in any patient. We observed no relevant side effects. Twelve-month survival after implantation of the LVAD was 89% representing a superior outcome compared with the fifth INTERMACS registry data with 75% survival. Two temporary extracorporeal membrane-oxygenation implantations were necessary due to intraoperative right ventricular dysfunction. Only one patient died 5 weeks after LVAD implantation of multiorgan failure, five patients were successfully transplanted, and three patients underwent LVAD implantation for destination therapy. Levosimendan might improve clinical outcome and survival when used as pretreatment in patients with right heart insufficiency prior to LVAD implantation. However, we recommend a larger controlled trial in the future to confirm our preliminary results.

A review of cardiac transplantation

Perioperative anesthetic management for cardiac transplantation is reviewed. Recent developments in adult cardiac transplantation are noted. This review includes demographics and historical results, recipient and donor selection and evaluation, mechanical circulatory support and heart transplantation techniques, and patient management immediately postimplantation.

Primary graft failure after heart transplantation

Primary graft failure (PGF) is a devastating complication that occurs in the immediate postoperative period following heart transplantation. It manifests as severe ventricular dysfunction of the donor graft and carries significant mortality and morbidity. In the last decade, advances in pharmacological treatment and mechanical circulatory support have improved the outlook for heart transplant recipients who develop this complication. Despite these advances in treatment, PGF is still the leading cause of death in the first 30 days after transplantation. In today's climate of significant organ shortages and growing waiting lists, transplant units worldwide have increasingly utilised "marginal donors" to try and bridge the gap between "supply and demand." One of the costs of this strategy has been an increased incidence of PGF. As the threat of PGF increases, the challenges of predicting and preventing its occurrence, as well as the identification of more effective treatment modalities, are vital areas of active research and development.