Abstract

BACKGROUND Preoperative anaemia is a risk factor for adverse postoperative outcomes after cardiac surgery. Iron deficiency is a frequent cause of low preoperative haemoglobin. An effective treatment for preoperative anaemia associated with iron deficiency has not been determined. METHODS We conducted a single-centre, open-label, pragmatic randomised trial, enrolling 156 elective cardiac surgery patients who had low preoperative haemoglobin (100-130 g L(-1)) with iron deficiency (serum ferritin <100 μg L(-1) or transferrin saturation <30%) to compare intravenous ferric derisomaltose 1000 mg and darbepoetin 200 μg subcutaneously (intervention group) with oral ferrous sulphate 600 mg daily (control group). The primary outcome was transfusion of at least one unit of allogeneic red cells during surgery and within the following 5 days. Secondary outcomes included the change in haemoglobin concentration between randomisation and surgery, red cell transfusion volume, postoperative blood loss, pre-specified postoperative complications, length of hospital stay, and in-hospital death. RESULTS The odds of red cell transfusion were lower in the intervention group compared with the control group (adjusted odds ratio=0.33; 95% confidence interval [CI], 0.15-0.75; P=0.008). Of the secondary outcomes, the only significant difference was the increase in haemoglobin between randomisation and surgery, intervention vs control 9.5 g L(-1) (95% CI, 6.8-12.2; P<0.001). CONCLUSIONS In patients with a low preoperative haemoglobin and iron deficiency, preoperative treatment with a single dose of ferric derisomaltose and darbepoetin decreased the proportion of participants who received a perioperative blood transfusion as a consequence of a greater increase in haemoglobin compared with treatment with oral ferrous sulphate. CLINICAL TRIAL REGISTRATION ISRCTN Number: 41421863; EUDRACT number: 2011-003695-36.

Abstract

BACKGROUND Low preoperative haemoglobin is frequently observed in heart surgery patients and is associated with a significant decrease in haemoglobin between post-operative days 2 and 3, known as haemoglobin drift. Overall, these patients tend to receive many RBC transfusions. Since iron homeostasis is often impaired in these patients, restoration of iron availability might override iron-restricted erythropoiesis. However, reduced tolerance to oral iron salts has limited this strategy to intravenous iron administration. STUDY DESIGN AND METHODS The purpose of this study was to assess whether preoperative supplementation with oral sucrosomial iron, a new iron-delivery technology with improved tolerance and bioavailability, might be an effective strategy for this patient population. One thousand consecutive patients were randomized and received either a one-month course of sucrosomial iron (60 mg/day) or no treatment prior to elective heart surgery at a single high-volume centre (ClinicalTrials.gov NCT03560687). Primary end-points were haemoglobin concentration on the day of hospital admittance and number of blood transfusions. Secondary end-points were haemoglobin drift, tolerance of treatment and cost-effectiveness of sucrosomial iron administration. RESULTS Baseline haemoglobin in the treatment group was higher (by 0.67 g/dL; p<0.001) than that in the control group. The percentage of patients in the treatment group who required transfusion (35.4%) was half that in the control group (64.6%). The average number of transfused units per operation was 0.95 vs. 2.03 in the treatment and control groups, respectively. Haemoglobin drift was substantially similar in the two groups, and the tolerability of treatment was excellent (98%). The overall cost of treatment was 156 Euros less in the treatment group, expressed as a raw cost of transfusion. CONCLUSION In elective heart surgery, routine preoperative sucrosomial iron administration seems to be a safe, well-tolerated and cost-effective strategy to increase preoperative haemoglobin and reduce the need for allogeneic blood transfusions.

Abstract

AIMS: Heart transplant recipients have reduced exercise capacity despite preserved graft function. The IronIC trial was designed to test the hypothesis that intravenous iron therapy would improve peak oxygen consumption in these patients. METHODS AND RESULTS This randomized, placebo-controlled, double-blind trial was performed at our national center for heart transplantation. One hundred and 2 heart transplant recipients with a serum ferritin <100 µg/liter or 100 to 300 µg/liter, in combination with transferrin saturation of <20%, and hemoglobin level >100 g/liter were enrolled ≥1 year after transplantation. A cardiopulmonary exercise test was performed before administration of the study drug and at 6 months follow-up. The primary endpoint was peak oxygen consumption. Key secondary outcomes included iron status, handgrip strength, quality of life, and safety. Fifty-two patients were randomized to receive ferric derisomaltose 20 mg/kg, and 50 to placebo. The between-group difference in baseline-adjusted peak oxygen consumption was 0.3 ml/kg/min (95% confidence interval -0.9 to 1.4, p = 0.66). In patients with a baseline ferritin <30 µg/liter, peak oxygen consumption was significantly higher in the ferric derisomaltose arm. At 6 months, iron stores were restored in 86% of the patients receiving ferric derisomaltose vs 20% in patients receiving placebo (p < 0.001). Quality of life was significantly better in patients receiving ferric derisomaltose. Twenty-seven adverse events occurred in the intravenous iron group vs 30 in the placebo group (p = 0.39). CONCLUSION Intravenous iron treatment did not improve peak oxygen consumption in heart transplant recipients with ferritin <100 µg/liter or 100 to 300 µg/liter in combination with transferrin saturation <20%. TRIAL REGISTRATION NUMBER http//www.clinicaltrials.gov identifier NCT03662789.

Abstract

AIMS: Iron deficiency is common in heart failure with reduced ejection fraction (HFrEF) and negatively affects cardiac function and structure. The study the effect of ferric carboxymaltose (FCM) on cardiac reverse remodelling and contractile status in HFrEF. METHODS AND RESULTS Symptomatic HFrEF patients with iron deficiency and a persistently reduced left ventricular ejection fraction (LVEF <45%) at least 6 months after cardiac resynchronization therapy (CRT) implant were prospectively randomized to FCM or standard of care (SOC) in a double-blind manner. The primary endpoint was the change in LVEF from baseline to 3-month follow-up assessed by three-dimensional echocardiography. Secondary endpoints included the change in left ventricular end-systolic (LVESV) and end-diastolic volume (LVEDV) from baseline to 3-month follow-up. Cardiac performance was evaluated by the force-frequency relationship as assessed by the slope change of the cardiac contractility index (CCI = systolic blood pressure/LVESV index) at 70, 90, and 110 beats of biventricular pacing. A total of 75 patients were randomized to FCM (n = 37) or SOC (n = 38). At baseline, both treatment groups were well matched including baseline LVEF (34 ± 7 vs. 33 ± 8, P = 0.411). After 3 months, the change in LVEF was significantly higher in the FMC group [+4.22%, 95% confidence interval (CI) +3.05%; +5.38%] than in the SOC group (-0.23%, 95% CI -1.44%; +0.97%; P < 0.001). Similarly, LVESV (-9.72 mL, 95% CI -13.5 mL; -5.93 mL vs. -1.83 mL, 95% CI -5.7 mL; 2.1 mL; P = 0.001), but not LVEDV (P = 0.748), improved in the FCM vs. the SOC group. At baseline, both treatment groups demonstrated a negative force-frequency relationship, as defined by a decrease in CCI at higher heart rates (negative slope). FCM resulted in an improvement in the CCI slope during incremental biventricular pacing, with a positive force-frequency relationship at 3 months. Functional status and exercise capacity, as measured by the Kansas City Cardiomyopathy Questionnaire and peak oxygen consumption, were improved by FCM. CONCLUSIONS Treatment with FCM in HFrEF patients with iron deficiency and persistently reduced LVEF after CRT results in an improvement of cardiac function measured by LVEF, LVESV, and cardiac force-frequency relationship.

Abstract

PURPOSE Iron supplementation has been evaluated in several randomized controlled trials (RCTs) for its potential to increase baseline hemoglobin and decrease red blood cell transfusion during cardiac surgery. This study's main objective was to evaluate the current evidence for iron administration in cardiac surgery patients. METHODS We searched MEDLINE, EMBASE, CENTRAL, Web of Science databases, and Google Scholar from inception to 19 November 2020 for RCTs evaluating perioperative iron administration in adult patients undergoing cardiac surgery. The RCTs were assessed using a risk of bias assessment and the quality of evidence was assessed using the grading of recommendations, assessments, development, and evaluations. RESULTS We reviewed 1,767 citations, and five studies (n = 554) met the inclusion criteria. The use of iron showed no statistical difference in incidence of transfusion (risk ratio, 0.86; 95% confidence interval, 0.65 to 1.13). Trial sequential analysis suggested an optimal information size of 1,132 participants, which the accrued information size did not reach. CONCLUSION The current literature does not support or refute the routine use of iron therapy in cardiac surgery patients. TRIAL REGISTRATION PROSPERO (CRD42020161927); registered 19 December 2019.

Abstract

OBJECTIVES The benefits of preoperative intravenous (IV) iron treatment in cardiac surgery patients with preoperative anaemia or iron deficiency have not been well-established. We performed a systematic review and meta-analysis to determine the effects of treating preoperative anaemia or iron deficiency with IV iron in adult cardiac surgery patients. METHODS We searched Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval Systems Online and Excerpta Medica Database for randomized controlled trials (RCTs) and observational studies comparing IV iron to oral iron or no iron. We performed title and abstract, full-text screening, data extraction and risk of bias assessment independently and in duplicate. We pooled data using a random effects model and evaluated the overall quality of evidence. RESULTS We identified 4 RCTs and 7 observational studies. Pooled data from observational studies suggested a benefit of IV iron compared to no iron on mortality [relative risk 0.39, 95% confidence interval (CI) 0.23-0.65; P < 0.001, very low quality], units transfused per patient (mean difference -1.22, 95% CI -1.85 to -0.60; P < 0.001, very low quality), renal injury (relative risk 0.50, 95% CI 0.36-0.69; P < 0.001, very low quality) and hospital length of stay (mean difference -4.24 days, 95% CI -6.86 to -1.63; P = 0.001, very low quality). Pooled data from RCTs demonstrated a reduction in the number of patients transfused with IV iron compared to oral or no iron (relative risk 0.81, 95% CI 0.70-0.94; P = 0.005, moderate quality). The pooled estimates of effect from RCTs for mortality, hospital length of stay, units transfused per patient and renal injury were consistent in direction with observational studies. CONCLUSIONS This meta-analysis suggests that IV iron improves postoperative morbidity in adult cardiac surgery patients with preoperative anaemia or iron deficiency. A large, rigorous, placebo-controlled, double-blinded, multicentre trial is needed to clarify the role of IV iron in this patient population. CLINICAL TRIAL REGISTRATION International prospective register of systematic reviews ID Number CRD42019122844.

Abstract

In patients with pre-operative anaemia undergoing cardiac surgery, combination treatment with intravenous iron, subcutaneous erythropoietin alpha, vitamin B12 and oral folic acid reduces allogeneic blood product transfusions. It is unclear if certain types of anaemia particularly benefit from this treatment. We performed a post-hoc analysis of anaemic patients from a randomised trial on the 'Effect of ultra-short-term treatment of patients with iron deficiency or anaemia undergoing cardiac surgery'. We used linear regression analyses to examine the efficacy of a combination anaemia treatment compared with placebo on the following deficiencies, each representing a part of the combination treatment: ferritin and transferrin saturation; endogenous erythropoietin; holotranscobalamine; and folic acid in erythrocytes. Efficacy was defined as change in reticulocyte count from baseline to the first, third and fifth postoperative days and represented erythropoietic activity in the immediate peri-operative recovery phase. In all 253 anaemic patients, iron deficiency was the most common cause of anaemia. Treatment significantly increased reticulocyte count in all regression analyses on postoperative days 1, 3 and 5 (all p < 0.001). Baseline ferritin and endogenous erythropoietin were negatively associated with change in reticulocyte count on postoperative day 5, with an unstandardised regression coefficient B of -0.08 (95%CI -0.14 to -0.02) and -0.14 (95%CI -0.23 to -0.06), respectively. Quadruple anaemia treatment was effective regardless of the cause of anaemia and its effect manifested early in the peri-operative recovery phase. The more pronounced a deficiency was, the stronger the subsequent boost to erythropoiesis may have been.

Abstract

BACKGROUND Anemia is common in cardiac surgery affecting 25-40% of patients and associated with increased blood transfusions, morbidity, mortality, and higher hospital costs. Higher rates of stroke, acute renal injury, and total number of adverse postoperative outcomes have also been reported to be associated with preoperative anemia. This systematic review assessed the current evidence for preoperative intravenous iron on major outcomes following cardiac surgery. METHODS Outcome measures included postoperative hemoglobin, transfusion rates, major adverse events, and mortality. The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and articles were identified using PubMed, Cochrane, CLINAHL, WOS, and EMBASE databases. Articles were included if they compared patients with and without preoperative anemia based on treatment with intravenous iron. Quality was assessed using Cochrane Risk of Bias Tool and Newcastle-Ottawa scale, and strength of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. RESULTS Of the articles reviewed, six met inclusion criteria. These included four randomized double-blind prospective cohort studies, one randomized non-blinded prospective study, and one non-randomized non-blinded prospective study with historical control. Across studies, 1,038 patients were enrolled. Two studies showed higher hemoglobin with iron therapy, and only one study showed significant differences in multiple outcomes such as transfusion and morbidity. CONCLUSIONS Given the paucity of studies and biases within them, the current evidence for treatment with intravenous iron prior to cardiac surgery is weak. More evidence is needed to support the administration of preoperative intravenous iron in cardiac surgery patients.

Abstract

OF OBJECTIVES Heart transplant recipients have reduced exercise capacity despite preserved graft function. Numerous mechanisms may contribute to this impaired exercise tolerance, one of which may be iron deficiency (ID). Among our heart transplant survivors, 48 % have ID. The IronIC trial (NCT03662789) was designed to test the hypothesis that intravenous (i.v.) iron therapy will improve exercise capacity assessed by peak oxygen consumption. METHODS 102 stable, cardiac transplant recipients with ID, defined as serum ferritin <100 microg/l, or ferritin between 100 and 300 microg/l in combination with transferrin saturation <20 %, have been randomized in a 1:1 manner to treatment with intravenous iron isomaltoside, 20 mg/kg, or NaCl. Care was taken to blind patients and personnel to the color of the infusate. All participants provided written, informed consent. Exclusion criteria included hemoglobin <100 g/l, red blood cell disorders, end-stage kidney failure, intolerance to iron isomaltoside, and ongoing infections or rejections. Prior to the intervention, all patients underwent a treadmill test to measure peak oxygen consumption. Muscle strength by a hand grip test, cognitive function, and self-reported quality of life were also measured. All tests are repeated at follow-up 6 months after intervention. The trial is powered to detect a 1.5 ml/kg/min between-group difference in the change in peak oxygen consumption. Last patient is scheduled for follow-up February 2020. ENDPOINTS The primary objective is to assess baseline-adjusted peak oxygen consumption, six months after one single dose of iron isomaltoside. Secondary objectives are to assess the impact of treatment on iron stores, muscle strength, cognitive function, quality of life, safety and tolerability. This study will give insight to whether heart transplant recipients with ID can benefit from intravenous iron supplement. Results will be ready for presentation at the 2020 ISHLT conference.

Abstract

BACKGROUND Anaemia and iron deficiency are frequent in patients scheduled for cardiac surgery. This study assessed whether immediate preoperative treatment could result in reduced perioperative red blood cell (RBC) transfusions and improved outcome. METHODS In this single-centre, randomised, double-blind, parallel-group controlled study, patients undergoing elective cardiac surgery with anaemia (n=253; haemoglobin concentration (Hb) <120 g/L in women and Hb <130 g/L in men) or isolated iron deficiency (n=252; ferritin <100 mcg/L, no anaemia) were enrolled. Participants were randomly assigned (1:1) with the use of a computer-generated range minimisation (allocation probability 0.8) to receive either placebo or combination treatment consisting of a slow infusion of 20 mg/kg ferric carboxymaltose, 40 000 U subcutaneous erythropoietin alpha, 1 mg subcutaneous vitamin B12, and 5 mg oral folic acid or placebo on the day before surgery. Primary outcome was the number of RBC transfusions during the first 7 days. This trial is registered with ClinicalTrials.gov, number NCT02031289. FINDINGS Between Jan 9, 2014, and July 19, 2017, 1006 patients were enrolled; 505 with anaemia or isolated iron deficiency and 501 in the registry. The combination treatment significantly reduced RBC transfusions from a median of one unit in the placebo group (IQR 0-3) to zero units in the treatment group (0-2, during the first 7 days (odds ratio 0.70 [95% CI 0.50-0.98] for each threshold of number of RBC transfusions, p=0.036) and until postoperative day 90 (p=0.018). Despite fewer RBC units transfused, patients in the treatment group had a higher haemoglobin concentration, higher reticulocyte count, and a higher reticulocyte haemoglobin content during the first 7 days (p≤0.001). Combined allogeneic transfusions were less in the treatment group (0 [IQR 0-2]) versus the placebo group (1 [0-3]) during the first 7 days (p=0.038) and until postoperative day 90 (p=0.019). 73 (30%) serious adverse events were reported in the treatment group group versus 79 (33%) in the placebo group. INTERPRETATION An ultra-short-term combination treatment with intravenous iron, subcutaneous erythropoietin alpha, vitamin B12, and oral folic acid reduced RBC and total allogeneic blood product transfusions in patients with preoperative anaemia or isolated iron deficiency undergoing elective cardiac surgery. FUNDING Vifor Pharma and Swiss Foundation for Anaesthesia Research.