Long-term (> 8 weeks) home inotropic therapy as destination therapy in patients with advanced heart failure or as bridge to heart transplantation

Inotropes in Patients with Advanced Heart Failure: Not Only Palliative Care

Patients with advanced heart failure suffer from severe and persistent symptoms, often not responding disease-modifying drugs, a marked limitation of functional capacity and poor quality of life that can ameliorate with inotropic drugs therapy. In small studies, pulsed infusions of classical inotropes (ie, dobutamine and milrinone) are associated with improvement in hemodynamic parameters and quality of life in patients with advanced heart failure. However, because of the adverse effects of these drugs, serious safety issues have been raised. Levosimendan is a calcium-sensitizing inodilators with a triple mechanism of action, whose infusion results in hemodynamic, neurohormonal, and inflammatory cytokine improvements in patients with chronic advanced HF. In addition, levosimendan has important pleiotropic effects, including protection of myocardial, renal, and liver cells from ischemia-reperfusion injury, and anti-inflammatory and antioxidant effects; these properties possibly make levosimendan an "organ protective" inodilator. In clinical trials and real-world evidence, infusion of levosimendan at fixed intervals is safe and effective in patients with advanced HF, alleviating clinical symptoms, reducing hospitalizations, and improving the quality of life. Therefore, the use of repeated doses of levosimendan could represent the therapy of choice as a bridge to transplant/left ventricular assist device implantation or as palliative therapy in patients with advanced heart failure.

Current Status of Inotropes in Heart Failure

Inotropes are medications that improve the contractility of the heart and are used in patients with low cardiac output or evidence of end-organ dysfunction. Since their initial discovery, inotropes have held promise in alleviating symptoms and potentially increasing longevity in such patients. Decades of intensive study have further elucidated the benefits and risks of using inotropes. In this article, the authors discuss the history of inotropes, their indications, mechanism of action, and current guidelines pertaining to their use in heart failure. The authors provide insight into their appropriate use and related shortcomings and the practical aspects of inotrope use.

Novel role of phosphodiesterase inhibitors in the management of end-stage heart failure

In advanced heart failure (HF), chronic inotropic therapy with intravenous milrinone, a phosphodiesterase III inhibitor, is used as a bridge to advanced management that includes transplantation, ventricular assist device implantation, or palliation. This is especially true when repeated attempts to wean off inotropic support result in symptomatic hypotension, worsened symptoms, and/or progressive organ dysfunction. Unfortunately, patients in this clinical predicament are considered hemodynamically labile and may escape the benefits of guideline-directed HF therapy. In this scenario, chronic milrinone infusion may be beneficial as a bridge to introduction of evidence based HF therapy. However, this strategy is not well studied, and in general, chronic inotropic infusion is discouraged due to potential cardiotoxicity that accelerates disease progression and proarrhythmic effects that increase sudden death. Alternatively, chronic inotropic support with milrinone infusion is a unique opportunity in advanced HF. This review discusses evidence that long-term intravenous milrinone support may allow introduction of beta blocker (BB) therapy. When used together, milrinone does not attenuate the clinical benefits of BB therapy while BB mitigates cardiotoxic effects of milrinone. In addition, BB therapy decreases the risk of adverse arrhythmias associated with milrinone. We propose that advanced HF patients who are intolerant to BB therapy may benefit from a trial of intravenous milrinone as a bridge to BB initiation. The discussed clinical scenarios demonstrate that concomitant treatment with milrinone infusion and BB therapy does not adversely impact standard HF therapy and may improve left ventricular function and morbidity associated with advanced HF.

Intravenous home inotropic use is safe in pediatric patients awaiting transplantation

BACKGROUND

Intravenous inotropic therapy can be used to support children awaiting heart transplantation. Although use of this therapy is discouraged in adults because of poor outcomes, its use in children, particularly outpatient, has had limited evaluation. We aimed to evaluate the safety and efficacy of this practice.

METHODS AND RESULTS

A retrospective analysis of an intent to treat protocol was completed on United Network for Organ Sharing status 1A patients discharged on inotropic therapy from 1999 until 2012. Intravenous inotropic therapy was initiated for cardiac symptoms not amenable to oral therapy. Patients who were not status 1A or required >1 inotrope were excluded. Efficacy was analyzed by time to first event: transplantation; readmission until transplantation; improvement leading to inotrope withdrawal; or death. Safety included analysis of infection rates, line malfunctions, temporary hospitalization, neurological events, and arrhythmias. One hundred six patients met inclusion criteria. The mean age was 10.1±6.4 years, 47% of patients had congenital heart disease, and 80% of these patients had single ventricle physiology. In patients without congenital heart disease, 53% had dilated cardiomyopathy, 91% of patients received milrinone, 85% of patients underwent transplantation, 8% of patients successfully weaned from support as outpatients, whereas 6% died. Fifty percent of patients were readmitted before transplantation or weaning from support, of which 64% required only 1 readmission. The majority of readmissions were for heart failure.

CONCLUSIONS

Outpatient intravenous inotropic therapy can be safely used as a bridge to transplantation in pediatric patients. A minority of patients can discontinue inotropic therapy because of clinical improvement.

Review: The New Concept of ‘‘Interventional Heart Failure Therapy’’: Part 2—Inotropes, Valvular Disease, Pumps, and Transplantation

Recent advances in heart failure therapy include a variety of mechanical and device-based technologies that target structural aspects of heart failure that cannot be treated with drug therapy alone; these newer therapies can collectively be described as interventional heart failure therapy. This article is the second in a 2-part series reviewing interventional heart failure therapy. Interventions included in this discussion include those indicated for the treatment of end-stage refractory heart failure, including interventional medical therapy, interventional treatment of valvular disease, mechanical assist devices, and heart transplantation. Also included is a review of the currently available catheter-based pumps, which are intended to provide temporary support in patients with acute hemodynamic compromise. The use of cellular or stem cell therapy for the treatment of heart failure is an emerging interventional therapy and data supporting its use for the treatment heart failure will also be presented, as will a discussion of the role of palliative care and self-care in heart failure therapy.

Prognosis on chronic dobutamine or milrinone infusions for stage D heart failure

BACKGROUND

There are no published clinical trials comparing dobutamine with milrinone in outpatients with stage D heart failure on continuous inotropes.

METHODS AND RESULTS

In a retrospective analysis of 112 inotrope-dependent patients with stage D heart failure who were not transplant candidates at enrollment, we investigated the relationship between choice of dobutamine or milrinone and mortality. Half the patients were on dobutamine (mean dose, 5.4+/-2.5 microg/kg per minute) and half on milrinone (mean dose, 0.4+/-0.2 microg/kg per minute). Those on dobutamine tended to be older (63 years old versus 54 years old), male (86% versus 79%), and fewer had implantable cardioverter-defibrillators (57% versus 74%). During a median follow-up time of 130 days (range, 2 to 2345 days), there were 85 deaths (76% of cohort) and 55 rehospitalizations. Use of dobutamine compared with milrinone was associated with higher all-cause mortality in an unadjusted analysis (hazard ratio [HR], 1.63; 95% CI, 1.06 to 2.52; P<0.03). However, this association was not significant after adjustment for baseline characteristics in the full cohort (N=112; HR, 0.99; 95% CI 0.5 to 1.97; P=0.98) or propensity-matched cohort (N=70; HR, 0.94; 95% CI 0.48 to 1.85; P=0.86).

CONCLUSIONS

In this single-center retrospective study, there were no mortality differences between chronic intravenous dobutamine or milrinone in patients with stage D heart failure being discharged from the hospital. The high mortality in this group selected for inotrope dependence warrants careful consideration of all options and priorities for further care.

The use of positive inotropes in end-of-life heart failure care

End-stage heart failure is associated with mortality equivalent to cancer, yet there is little information about palliative therapy for this disease. Chronic outpatient support with inotropes provides symptomatic relief and life extension for those select patients demonstrating dependence on positive inotropic therapy. The purpose of this review is to provide information about process and implementation of chronic outpatient support with inotropes in patients with end-stage heart failure.