Thomas J. Povsic

Intramyocardial, Autologous CD34+ Cell Therapy for Refractory Angina

Rationale: A growing number of patients with coronary disease have refractory angina. Preclinical and early-phase clinical data suggest that intramyocardial injection of autologous CD34+ cells can improve myocardial perfusion and function. Objective: Evaluate the safety and bioactivity of intramyocardial injections of autologous CD34+ cells in patients with refractory angina who have exhausted all other treatment options. Methods and Results: In this prospective, double-blind, randomized, phase II study (ClinicalTrials.gov identifier: NCT00300053), 167 patients with refractory angina received 1 of 2 doses (1×105 or 5×105 cells/kg) of mobilized autologous CD34+ cells or an equal volume of diluent (placebo). Treatment was distributed into 10 sites of ischemic, viable myocardium with a NOGA mapping injection catheter. The primary outcome measure was weekly angina frequency 6 months after treatment. Weekly angina frequency was significantly lower in the low-dose group than in placebo-treated patients at both 6 months (6.8±1.1 versus 10.9±1.2, P=0.020) and 12 months (6.3±1.2 versus 11.0±1.2, P=0.035); measurements in the high-dose group were also lower, but not significantly. Similarly, improvement in exercise tolerance was significantly greater in low-dose patients than in placebo-treated patients (6 months: 139±151 versus 69±122 seconds, P=0.014; 12 months: 140±171 versus 58±146 seconds, P=0.017) and greater, but not significantly, in the high-dose group. During cell mobilization and collection, 4.6% of patients had cardiac enzyme elevations consistent with non-ST segment elevation myocardial infarction. Mortality at 12 months was 5.4% in the placebo-treatment group with no deaths among cell-treated patients. Conclusions: Patients with refractory angina who received intramyocardial injections of autologous CD34+ cells (105 cells/kg) experienced significant improvements in angina frequency and exercise tolerance. The cell-mobilization and -collection procedures were associated with cardiac enzyme elevations, which will be addressed in future studies.

Intravenous Erythropoietin in Patients With ST-Segment Elevation Myocardial Infarction: REVEAL: A Randomized Controlled Trial

CONTEXT Acute ST-segment elevation myocardial infarction (STEMI) is a leading cause of morbidity and mortality. In experimental models of MI, erythropoietin reduces infarct size and improves left ventricular (LV) function. OBJECTIVE To evaluate the safety and efficacy of a single intravenous bolus of epoetin alfa in patients with STEMI. DESIGN, SETTING, AND PATIENTS A prospective, randomized, double-blind, placebo-controlled trial with a dose-escalation safety phase and a single dose (60,000 U of epoetin alfa) efficacy phase; the Reduction of Infarct Expansion and Ventricular Remodeling With Erythropoietin After Large Myocardial Infarction (REVEAL) trial was conducted at 28 US sites between October 2006 and February 2010, and included 222 patients with STEMI who underwent successful percutaneous coronary intervention (PCI) as a primary or rescue reperfusion strategy. INTERVENTION Participants were randomly assigned to treatment with intravenous epoetin alfa or matching saline placebo administered within 4 hours of reperfusion. MAIN OUTCOME MEASURE Infarct size, expressed as percentage of LV mass, assessed by cardiac magnetic resonance (CMR) imaging performed 2 to 6 days after study medication administration (first CMR) and again 12 ± 2 weeks later (second CMR). RESULTS In the efficacy cohort, the infarct size did not differ between groups on either the first CMR scan (n = 136; 15.8% LV mass [95% confidence interval {CI}, 13.3-18.2% LV mass] for the epoetin alfa group vs 15.0% LV mass [95% CI, 12.6-17.3% LV mass] for the placebo group; P = .67) or on the second CMR scan (n = 124; 10.6% LV mass [95% CI, 8.4-12.8% LV mass] vs 10.4% LV mass [95% CI, 8.5-12.3% LV mass], respectively; P = .89). In a prespecified analysis of patients aged 70 years or older (n = 21), the mean infarct size within the first week (first CMR) was larger in the epoetin alfa group (19.9% LV mass; 95% CI, 14.0-25.7% LV mass) than in the placebo group (11.7% LV mass; 95% CI, 7.2-16.1% LV mass) (P = .03). In the safety cohort, of the 125 patients who received epoetin alfa, the composite outcome of death, MI, stroke, or stent thrombosis occurred in 5 (4.0%; 95% CI, 1.31%-9.09%) but in none of the 97 who received placebo (P = .04). CONCLUSIONS In patients with STEMI who had successful reperfusion with primary or rescue PCI, a single intravenous bolus of epoetin alfa within 4 hours of PCI did not reduce infarct size and was associated with higher rates of adverse cardiovascular events. Subgroup analyses raised concerns about an increase in infarct size among older patients. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00378352.

Transcriptional Regulation of Bim by FOXO3a and Akt Mediates Scleroderma Serum–Induced Apoptosis in Endothelial Progenitor Cells

Background— Endothelial progenitor cells (EPCs) contribute to vascular regeneration/repair and thus may protect against scleroderma vasculopathy. We aimed to determine whether circulating EPCs were reduced in scleroderma, whether scleroderma sera could induce EPC apoptosis, and, if so, what the underlying apoptotic signaling pathway was. Methods and Results— Circulating EPC levels were quantified in 54 patients with scleroderma and 18 healthy control subjects by colony-forming unit assay and flow cytometry, which revealed markedly decreased EPC levels in scleroderma patients relative to healthy subjects. Substantial apoptosis was detected in EPCs after culturing in the presence of scleroderma sera compared with normal sera. Intriguingly, depletion of the IgG fraction from scleroderma sera completely abolished the apoptotic effects. Furthermore, scleroderma sera inhibited the activation/phosphorylation of Akt, which in turn suppressed the phosphorylation and degradation of forkhead transcription factor FKHRL1 (FOXO3a), resulting in the upregulation of apoptotic protein Bim. siRNA-mediated FOXO3a and Bim knockdown substantially reduced scleroderma serum–induced EPC apoptosis. Importantly, Bim expression and baseline apoptosis were increased in EPCs freshly isolated from scleroderma patients relative to that obtained from healthy subjects. Conclusion— Scleroderma serum–induced EPC apoptosis is mediated chiefly by the Akt-FOXO3a-Bim pathway, which may account, at least in part, for the decreased circulating EPC levels in scleroderma patients.

A phase 3, randomized, double-blinded, active-controlled, unblinded standard of care study assessing the efficacy and safety of intramyocardial autologous cd34+ cell administration in patients with refractory angina: Design of the renew study

Preclinical trials indicate that CD34+ cells represent an effective angiogenic stem cell component. Early-phase clinical trials suggest that intramyocardial administration of autologous CD34+ cells may improve functional capacity and symptoms of angina. RENEW is a pivotal phase 3 trial designed to determine the efficacy of granulocyte colony-stimulating factor (G-CSF)-mobilized CD34+ stem cells for the treatment for patients with refractory angina and chronic myocardial ischemia. Patients (n = 444) receiving maximally tolerated antianginal therapies and lacking conventional revascularization options with Canadian Cardiovascular Society class III or IV angina and ischemia on stress testing will be randomized 2:1:1 to cell therapy (G-CSF-mediated stem cell mobilization, apheresis, and intramyocardial injection of 1 × 10(5) autologous CD34(+) cells/kg), active control (G-CSF-mediated stem cell mobilization, apheresis, and intramyocardial placebo injection), or open-label standard of care. The primary efficacy end point is change in exercise treadmill time in the treated vs active control patients, with 90% power to detect a 60-second difference in exercise time between cell-treated (n = 200) and active control (n = 100) patients. Key secondary end points include total number of anginal episodes per week and the incidence of independently adjudicated major adverse cardiac events and serious adverse events. RENEW will be the first adequately powered study aimed at definitively determining the efficacy of a cell therapy (intramyocardially delivered autologous CD34+ cells) for improvement of functional capacity in patients with refractory angina.

Rate- and Rhythm-Control Therapies in Patients With Atrial Fibrillation: A Systematic Review

Atrial fibrillation (AF) is a major public health problem in the United States. More than 2.3 million Americans are estimated to have AF (1). The known association between AF and substantial mortality, morbidity, and health care costs compounds the effect of this condition. Not only is the risk for death in patients with AF twice that of patients without it, but AF can result in myocardial ischemia and infarction, exacerbate heart failure (HF), and cause tachycardia-induced cardiomyopathy if the ventricular rate is not well-controlled (25). The most dreaded complication of AF is thromboembolism, especially stroke (6). In some patients, AF or therapies to manage this condition can severely depreciate quality of life (710). Furthermore, the management of AF and its complications is responsible for nearly

A double-blind, randomized, controlled, multicenter study to assess the safety and cardiovascular effects of skeletal myoblast implantation by catheter delivery in patients with chronic heart failure after myocardial infarction.

16 billion in additional costs to the U.S. health care system per year (11). Despite the substantial public health effect of AF, uncertainties around its management remain. In particular, the comparative safety and effectiveness of different rate- and rhythm-control therapies for patients with AF are unclear. We conducted this systematic review to evaluate the comparative safety and effectiveness of rate- versus rhythm-control strategies; medications used for ventricular rate control; strict versus more lenient rate-control strategies; nonpharmacologic rate-control therapies versus medications; electrical cardioversion and antiarrhythmic medications for restoration of sinus rhythm; and catheter ablation, surgical ablation, and antiarrhythmic medications for maintenance of sinus rhythm. Methods We developed and followed a standard protocol for our review. Full details of our methods, search strategies, results, and conclusions are presented in a comparative effectiveness review commissioned by the Agency for Healthcare Research and Quality (AHRQ) and are available at www.effectivehealthcare.ahrq.gov (12). Data Sources and Searches We searched PubMed, EMBASE, and the Cochrane Database of Systematic Reviews for studies published between 1 January 2000 and 12 November 2013. Data before 2000 have been summarized in an AHRQ report on the management of new-onset AF published in 2001 (1315). Study Selection We identified randomized, controlled trials (RCTs) published in English that were comparative assessments of pharmacologic or nonpharmacologic rate- or rhythm-control therapies aimed at treating adults with AF. Observational studies were also allowed for comparisons of strict versus lenient rate control or cardiac resynchronization therapy versus other rhythm-control therapies. The following outcomes were considered: restoration of sinus rhythm (conversion), maintenance of sinus rhythm, recurrence of AF at 12 months, development of cardiomyopathy, death (all-cause and cardiac), myocardial infarction, cardiovascular hospitalizations, HF symptoms, control of AF symptoms, quality of life, functional status, stroke and other embolic events, bleeding events, and adverse effects of therapy. Data Extraction and Quality Assessment One investigator abstracted and another confirmed data related to study setting and design, patient characteristics, details of treatment, comparators, and relevant outcomes. The quality of individual studies was evaluated using the approach described in AHRQs Methods Guide for Effectiveness and Comparative Effectiveness Reviews (16). Investigators also assessed factors that limited applicability of the evidence. Data Synthesis and Analysis For each treatment comparison and outcome of interest, we determined the feasibility of completing a quantitative synthesis (meta-analysis) based on the volume of relevant literature, conceptual homogeneity of the studies (both in terms of study population and outcomes), and completeness of the reporting of results. We considered meta-analysis for outcomes that at least 3 studies reported. For our evaluation of rate- versus rhythm-control strategies, we grouped all rate-control strategies together and all rhythm-control strategies together, regardless of the specific medication or procedure. We grouped pharmacologic interventions by class, considering rate-controlling calcium-channel blockers and all -blockers each to be similar enough to be grouped together. We categorized procedures into electrical cardioversion, atrioventricular node (AVN) ablation, AF ablation by pulmonary vein isolation (PVI) (by open surgical, minimally invasive, or transcatheter procedures), and different types of surgical maze procedures and explored comparisons among these categories. In addition, for the comparisons focusing on medications versus procedures, we also explored grouping all medications together and comparing them with all procedures. When a meta-analysis was appropriate, we used a random-effects model to synthesize the available evidence quantitatively using Comprehensive Meta-Analysis, version 2 (Biostat, Englewood, New Jersey). We used a standardized approach to rank the overall strength of evidence (SOE) for each outcome (16). Role of the Funding Source Primary funding was provided by AHRQ. Neither the technical experts nor AHRQ representatives had a role in the literature search, data analysis, interpretation of the data, or decision to submit the manuscript for publication. Results We screened 10495 abstracts, evaluated 570 full-text articles, and included 200 articles representing 162 studies involving 28836 patients (Figure 1). Tables 1 to 6 of the Supplement provide details about these studies and their populations for each topic described here. Table 7 of the Supplement lists identified and potential limitations of the studies. The full AHRQ report highlights additional findings (12). Figure 1. Summary of evidence search and selection. AAD = antiarrhythmic drug; CRT = cardiac resynchronization therapy; RCT = randomized, controlled trial. * Some studies were relevant to more than 1 topic. Supplement. Tables Rate- Versus Rhythm-Control Strategies We included 16 RCTs in this analysis: 13 compared pharmacologic rhythm-control versus rate-control strategies (1729) and 3 compared a rhythm-control strategy with PVI versus a rate-control strategy that involved AVN ablation and implantation of a pacemaker in 1 study (30) and rate-controlling medications in the other 2 (31, 32). Ten RCTs (17, 18, 2022, 2428) provided information on outcomes of interest and were combined quantitatively (Figure 2). Of these, 5 included only patients with persistent AF (2022, 25, 28), 1 included only patients with paroxysmal AF (17), and 4 included patients with paroxysmal or persistent AF (18, 24, 26, 27). Two studies (17, 22) compared a single-chamber pacemaker plus AVN ablation versus a dual-chamber pacemaker plus AVN ablation plus an antiarrhythmic medication; all others compared largely unspecified rate-control with rhythm-control strategies. Figure 2. Meta-analysis forest plots. AAD = antiarrhythmic drug; PVI = pulmonary vein isolation. A. All-cause mortality for rate- vs. rhythm-control strategies. B. Cardiovascular mortality for rate- vs. rhythm-control strategies. C. Stroke for rate- vs. rhythm-control strategies. D. Restoration of sinus rhythm for monophasic vs. biphasic waveforms. E. Maintenance of sinus rhythm for PVI vs. AAD therapy. Figure 2. Continued. Data from the included studies showed moderate SOE that pharmacologic rate- and rhythm-control strategies are of comparable efficacy with regard to their effect on all-cause mortality (odds ratio [OR], 1.34 [95% CI, 0.89 to 2.02]; Q= 21.71; P= 0.003) (Figure 2, A) (18, 2022, 24, 2628), cardiac mortality (OR, 0.96 [CI, 0.77 to 1.20]; Q= 3.55; P= 0.47) (Figure 2, B) (18, 21, 22, 24, 25), and stroke (OR, 0.99 [CI, 0.76 to 1.30]; Q= 7.02; P= 0.43) (Figure 2, C) (17, 18, 2022, 24, 27, 28). Although the meta-analysis for all-cause mortality showed a potential benefit, it did not reach statistical significance and 6 of the 8 studies (6069 patients [95%]) had ORs that crossed 1, resulting in a final moderate SOE. For cardiac mortality (Figure 2, B), point estimates were inconsistent and CIs were wide for 2 of the 5 studies (18, 21), but there was no evidence of heterogeneity; therefore, our SOE rating was not affected. For the outcome of stroke, there was no evidence of heterogeneity, but the findings were mostly driven by 1 large, good-quality RCT (4060 patients), which was inconsistent with several of the smaller studies, reducing our confidence in the finding and in the SOE. These studies largely included older patients with mild AF symptoms. Three RCTs compared pharmacologic rate-control strategies with rhythm-control strategies using antiarrhythmic medications (17, 18, 22). These RCTs showed fewer cardiovascular hospitalizations with the rhythm-control strategies (17, 18, 22). Although data from 5 RCTs suggest that there is no difference between pharmacologic rate- and rhythm-control strategies in their effect on HF symptoms (17, 22, 24, 26, 46) (Table 1), a prespecified substudy of the Atrial Fibrillation and Congestive Heart Failure study showed that a higher proportion of time spent in sinus rhythm was associated with a greater improvement in New York Heart Association class (29). Table 1. Summary of SOE and Effect Estimates for Rate- Versus Rhythm-Control Strategies Three studies compared a rhythm-control strategy involving catheter ablation with a rate-control strategy involving rate-controlling medications (32) or AVN ablation combined with implantation of a pacemaker (30) or rate-controlling medications (31). One study showed that catheter ablation was better than pharmacologic rate control at improving symptoms, neurohormonal status, and objective physiologic exercise capacity (32). Another study showed that PVI isolation was superior to AVN ablation and pacemaker implantation in improving quality of life, 6-minute walk distance, and ejection fraction (30). Another study showed that PVI resulted in long-term restoration o

Clinically significant bleeding with low-dose rivaroxaban versus aspirin, in addition to P2Y12 inhibition, in acute coronary syndromes (GEMINI-ACS-1): a double-blind, multicentre, randomised trial

BACKGROUND We sought to determine the safety and preliminary efficacy of transcatheter intramyocardial administration of myoblasts in patients with heart failure (HF). METHODS MARVEL is a randomized placebo-controlled trial of image-guided, catheter-based intramyocardial injection of placebo or myoblasts (400 or 800 million) in patients with class II to IV HF and ejection fraction <35%. Primary end points were frequency of serious adverse events (safety) and changes in 6-minute walk test and Minnesota Living With HF score (efficacy). Of 330 patients intended for enrollment, 23 were randomized (MARVEL-1) before stopping the study for financial reasons. RESULTS At 6 months, similar numbers of events occurred in each group: 8 (placebo), 7 (low dose), and 8 (high dose), without deaths. Ventricular tachycardia responsive to amiodarone was more frequent in myoblast-treated patients: 1 (placebo), 3 (low dose), and 4 (high dose). A trend toward improvement in functional capacity was noted in myoblast-treated groups (Δ6-minute walk test of -3.6 vs +95.6 vs +85.5 m [placebo vs low dose vs high dose; P = .50]) without significant changes in Minnesota Living With HF scores. CONCLUSIONS In HF patients with chronic postinfarction cardiomyopathy, transcatheter administration of myoblasts in doses of 400 to 800 million cells is feasible and may lead to important clinical benefits. Ventricular tachycardia may be provoked by myoblast injection but appears to be a transient and treatable problem. A large-scale outcome trial of myoblast administration in HF patients with postinfarction cardiomyopathy is feasible and warranted.

Pre-existing anti–polyethylene glycol antibody linked to first-exposure allergic reactions to pegnivacogin, a PEGylated RNA aptamer

BACKGROUND Dual antiplatelet therapy (DAPT), aspirin plus a P2Y12 inhibitor, is the standard antithrombotic treatment following acute coronary syndromes. The factor Xa inhibitor rivaroxaban reduced mortality and ischaemic events when added to DAPT, but caused increased bleeding. The safety of a dual pathway antithrombotic therapy approach combining low-dose rivaroxaban (in place of aspirin) with a P2Y12 inhibitor has not been assesssed in acute coronary syndromes. We aimed to assess rivaroxaban 2·5 mg twice daily versus aspirin 100 mg daily, in addition to clopidogrel or ticagrelor (chosen at investigator discretion before randomisation), for patients with acute coronary syndromes started within 10 days after presentation and continued for 6-12 months. METHODS In this double-blind, multicentre, randomised trial (GEMINI-ACS-1) done at 371 clinical centres in 21 countries, eligible patients were older than 18 years with unstable angina, non-ST segment elevation myocardial infarction (NSTEMI) or ST segment elevation myocardial infarction (STEMI), with positive cardiac biomarkers and either ischaemic electrocardiographic changes or an atherosclerotic culprit lesion identified during angiography. Participants were randomly assigned (1:1) within 10 days after admission for the index acute coronary syndromes event to either aspirin or rivaroxaban based on a computer-generated randomisation schedule. Randomisation was balanced by using randomly permuted blocks with size of four and was stratified based on the background P2Y12 inhibitor (clopidogrel or ticagrelor) intended to be used at the time of randomisation. Investigators and patients were masked to treatment assignment. Patients received a minimum of 180 days of double-blind treatment with rivaroxaban 2·5 mg twice daily or aspirin 100 mg daily. The choice of clopidogrel or ticagrelor during trial conduct was not randomised and was based on investigator preference. The primary endpoint was thrombolysis in myocardial infarction (TIMI) clinically significant bleeding not related to coronary artery bypass grafting (CABG; major, minor, or requiring medical attention) up to day 390. Primary analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT02293395. FINDINGS Between April 22, 2015, and Oct 14, 2016, 3037 patients with acute coronary syndromes were randomly assigned; 1518 to receive aspirin and 1519 to receive rivaroxaban. 1704 patients (56%) were in the ticagrelor and 1333 (44%) in the clopidogrel strata. Median duration of treatment was 291 days (IQR 239-354). TIMI non-CABG clinically significant bleeding was similar with rivaroxaban versus aspirin therapy (total 154 patients [5%]; 80 participants [5%] of 1519 vs 74 participants [5%] of 1518; HR 1·09 [95% CI 0·80-1·50]; p=0·5840). INTERPRETATION A dual pathway antithrombotic therapy approach combining low-dose rivaroxaban with a P2Y12 inhibitor for the treatment of patients with acute coronary syndromes had similar risk of clinically significant bleeding as aspirin and a P2Y12 inhibitor. A larger, adequately powered trial would be required to definitively assess the efficacy and safety of this approach. FUNDING Janssen Research & Development and Bayer AG.

Cardiopoietic cell therapy for advanced ischemic heart failure: results at 39 weeks of the prospective, randomized, double blind, sham-controlled CHART-1 clinical trial

All 3 patients were female; 602-004 was treated at a site in Poland and the other 2 patients were treated in Germany. For additional information regarding these patients, see this article’s REG1-CLIN211a section in the Online Repository at www.jacionline. org. Note: As substantially more information is available on these 3 subjects than for other trial participants, inferences regarding the possible role of sex, geography, or allergic history are cautioned against. D, Dermal; GI, gastrointestinal; H, hypotension; H1, H1 blocker; H2, H2 blocker; I, intubation; Inh, inhalers; IVV, intravenous vasopressors; IVF, intravenous fluid resuscitation; P, pulmonary; S, steroids. To the Editor: Nucleic acid aptamers are a novel class of drugs that can be selected to inhibit targets of interest, including protein-protein interactions. Pegnivacogin is a 29-fluoropyrimidine–modified RNA aptamer that inhibits coagulation factor IXa, coupled to an approximately 40-kDa branched molecule of methoxypolyethylene glycol (mPEG), to increase its concentration and half-life in plasma. During the RADAR phase 2b clinical trial in patients with acute coronary syndrome, allergic reactions occurred within minutes of a first dose of pegnivacogin in 3 of 640 patients (Table I). Two met criteria for anaphylaxis, and 1 was an isolated dermal reaction; each event was deemed serious, and 1 life-threatening, and together they led to early termination of the trial. In a broad investigation into a cause for these 3 events (detailed in Methods in this article’s Online Repository at www. jacionline.org), a clinical database review found no other serious allergic reactions (SARs) to pegnivacogin; a quality analysis found no aggregation, degradation, or other deviations of the study product from specifications; and a primate pharmacology study found no evidence that pegnivacogin caused an inflammatory response, histamine release, or complement activation. However, blinded testing of more than half of all RADAR patients identified an association between high levels of antibody to polyethylene glycol (PEG) and the first-exposure allergic reactions. In addition to the immediate relevance, our findings are the first to document the potential clinical significance of pre-existing antibody to PEG, a component of numerous consumer and medicinal products. Initially, coded samples from31RADARpatientswere tested for anti-PEG antibody (see Analytical methods and Fig E1 in this article’s Online Repository at www.jacionline.org) in 2 ELISAs to detect IgGbinding to pegloticase, a PEGylated urate oxidase (a protein not expressed in humans), and to the 40-kDamPEGcomponent of pegnivacogin. Unblinding of the data revealed that samples giving the highest signals in both ELISAs were from the 3 patients with SARs (predose from patients 418-008 and 406-003; 88-day postinfusion from patient 602-004 from whom no predose sample was available). Direct (Fig 1, A) and competition ELISAs (Fig 1, B) showed that antibody from each patient could bind to linear and branched PEGs of 5 to 40 kDa, presented as free mPEG or PEG-diol (lacking methoxy termini), or when conjugated via different linkages to 2 proteins and pegnivacogin; importantly,

Congestive Heart Failure Cardiopoietic Regenerative Therapy (CHART-1) trial design.

Aims Cardiopoietic cells, produced through cardiogenic conditioning of patients’ mesenchymal stem cells, have shown preliminary efficacy. The Congestive Heart Failure Cardiopoietic Regenerative Therapy (CHART-1) trial aimed to validate cardiopoiesis-based biotherapy in a larger heart failure cohort. Methods and results This multinational, randomized, double-blind, sham-controlled study was conducted in 39 hospitals. Patients with symptomatic ischaemic heart failure on guideline-directed therapy (n = 484) were screened; n = 348 underwent bone marrow harvest and mesenchymal stem cell expansion. Those achieving > 24 million mesenchymal stem cells (n = 315) were randomized to cardiopoietic cells delivered endomyocardially with a retention-enhanced catheter (n = 157) or sham procedure (n = 158). Procedures were performed as randomized in 271 patients (n = 120 cardiopoietic cells, n = 151 sham). The primary efficacy endpoint was a Finkelstein–Schoenfeld hierarchical composite (all-cause mortality, worsening heart failure, Minnesota Living with Heart Failure Questionnaire score, 6-min walk distance, left ventricular end-systolic volume, and ejection fraction) at 39 weeks. The primary outcome was neutral (Mann–Whitney estimator 0.54, 95% confidence interval [CI] 0.47–0.61 [value > 0.5 favours cell treatment], P = 0.27). Exploratory analyses suggested a benefit of cell treatment on the primary composite in patients with baseline left ventricular end-diastolic volume 200–370 mL (60% of patients) (Mann–Whitney estimator 0.61, 95% CI 0.52–0.70, P = 0.015). No difference was observed in serious adverse events. One (0.9%) cardiopoietic cell patient and 9 (5.4%) sham patients experienced aborted or sudden cardiac death. Conclusion The primary endpoint was neutral, with safety demonstrated across the cohort. Further evaluation of cardiopoietic cell therapy in patients with elevated end-diastolic volume is warranted.