Clinical Diagnostics of Fecal Calprotectin: a Comparative Study of Actim® Calprotectin and LIAISON® Calprotectin.

BACKGROUND: Fecal calprotectin (fCal) is an important surrogate biomarker of chronic inflammatory bowel disease (IBD): Crohn's disease and ulcerative colitis. Non-invasive, immunochromatographic rapid tests are excellent tools for the real-time monitoring of disease activity and reduce the need for invasive and costly colonoscopy procedures. METHODS: In this study the accuracy of fCal detection by the semi-quantitative Actim® Calprotectin and the quantitative automated LIAISON® Calprotectin assay was assessed on a panel of clinical stool samples. RESULTS: Of the 119 fecal samples tested, Actim® Calprotectin agreed on 94 samples (79.0%) with the reference test. Furthermore, of the positive samples detected with LIAISON® Calprotectin, 94.0% were interpreted as positive by Actim® Calprotectin. CONCLUSIONS: Actim® Calprotectin is a rapid test that can be utilized for the initial differentiation between negative and positive samples in an outpatient setting, thus helping to limit more laborious quantitative methods to positive samples.

Meta-Analysis of Cell-based CaRdiac stUdiEs (ACCRUE) in patients with acute myocardial infarction based on individual patient data.

RATIONALE: The meta-Analysis of Cell-based CaRdiac study is the first prospectively declared collaborative multinational database, including individual data of patients with ischemic heart disease treated with cell therapy. OBJECTIVE: We analyzed the safety and efficacy of intracoronary cell therapy after acute myocardial infarction (AMI), including individual patient data from 12 randomized trials (ASTAMI, Aalst, BOOST, BONAMI, CADUCEUS, FINCELL, REGENT, REPAIR-AMI, SCAMI, SWISS-AMI, TIME, LATE-TIME; n=1252). METHODS AND RESULTS: The primary end point was freedom from combined major adverse cardiac and cerebrovascular events (including all-cause death, AMI recurrance, stroke, and target vessel revascularization). The secondary end point was freedom from hard clinical end points (death, AMI recurrence, or stroke), assessed with random-effects meta-analyses and Cox regressions for interactions. Secondary efficacy end points included changes in end-diastolic volume, end-systolic volume, and ejection fraction, analyzed with random-effects meta-analyses and ANCOVA. We reported weighted mean differences between cell therapy and control groups. No effect of cell therapy on major adverse cardiac and cerebrovascular events (14.0% versus 16.3%; hazard ratio, 0.86; 95% confidence interval, 0.63-1.18) or death (1.4% versus 2.1%) or death/AMI recurrence/stroke (2.9% versus 4.7%) was identified in comparison with controls. No changes in ejection fraction (mean difference: 0.96%; 95% confidence interval, -0.2 to 2.1), end-diastolic volume, or systolic volume were observed compared with controls. These results were not influenced by anterior AMI location, reduced baseline ejection fraction, or the use of MRI for assessing left ventricular parameters. CONCLUSIONS: This meta-analysis of individual patient data from randomized trials in patients with recent AMI revealed that intracoronary cell therapy provided no benefit, in terms of clinical events or changes in left ventricular function. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01098591.

Exercise capacity is associated with endothelin-1 release during emotional excitement in coronary artery disease patients.

Endothelin-1 (ET-1), a potent vasoconstrictor, IL-6, and catecholamines are increased and heart rate variability [SD of normal to normal R-R intervals (SDNN)] decreased during emotional excitement, but individual responses vary. We tested the hypothesis that exercise capacity is associated with physiological responses caused by real-life emotional excitement. We measured the plasma levels of ET-1, IL-6, catecholamines, heart rate, and SDNN in enthusiastic male ice hockey spectators (n = 51; age, 59 ± 9 years) with stable coronary artery disease (CAD) at baseline and during the Finnish National Ice Hockey League's final play-off matches. Maximal exercise capacity (METs) by bicycle exercise test and left ventricular ejection fraction (LVEF) were measured on a separate day. ET-1 response from baseline to emotional excitement correlated with maximal METs (r = -0.30; P = 0.040). In a linear stepwise regression analysis age, body mass index (BMI), METs, LVEF, basal ET-1, and subjective experience of excitement were entered the model as independent variables to explain ET-1 response. This model explained 27% of ET-1 response (P = 0.003). Maximal METs were most strongly correlated with ET-1 response (ß = -0.45; partial correlation r = -0.43; P = 0.002), followed by BMI (ß = -0.31; partial correlation r = -0.31; P = 0.033) and LVEF (ß = -0.30; partial correlation r = -0.33; P = 0.023). Exercise capacity may protect against further cardiovascular events in CAD patients, because it is associated with reduced ET-1 release during emotional excitement.

The effect of bone marrow microenvironment on the functional properties of the therapeutic bone marrow-derived cells in patients with acute myocardial infarction.

BACKGROUND: Treatment of acute myocardial infarction with stem cell transplantation has achieved beneficial effects in many clinical trials. The bone marrow microenvironment of ST-elevation myocardial infarction (STEMI) patients has never been studied even though myocardial infarction is known to cause an imbalance in the acid-base status of these patients. The aim of this study was to assess if the blood gas levels in the bone marrow of STEMI patients affect the characteristics of the bone marrow cells (BMCs) and, furthermore, do they influence the change in cardiac function after autologous BMC transplantation. The arterial, venous and bone marrow blood gas concentrations were also compared. METHODS: Blood gas analysis of the bone marrow aspirate and peripheral blood was performed for 27 STEMI patients receiving autologous stem cell therapy after percutaneous coronary intervention. Cells from the bone marrow aspirate were further cultured and the bone marrow mesenchymal stem cell (MSC) proliferation rate was determined by MTT assay and the MSC osteogenic differentiation capacity by alkaline phosphatase (ALP) activity assay. All the patients underwent a 2D-echocardiography at baseline and 4 months after STEMI. RESULTS: As expected, the levels of pO(2), pCO(2), base excess and HCO(3) were similar in venous blood and bone marrow. Surprisingly, bone marrow showed significantly lower pH and Na(+) and elevated K(+) levels compared to arterial and venous blood. There was a positive correlation between the bone marrow pCO(2) and HCO(3) levels and MSC osteogenic differentiation capacity. In contrast, bone marrow pCO(2) and HCO(3) levels displayed a negative correlation with the proliferation rate of MSCs. Patients with the HCO(3) level below the median value exhibited a more marked change in LVEF after BMC treatment than patients with HCO(3) level above the median (11.13 ± 8.07% vs. 2.67 ± 11.89%, P = 0.014). CONCLUSIONS: Low bone marrow pCO(2) and HCO(3) levels may represent the optimal environment for BMCs in terms of their efficacy in autologous stem cell therapy in STEMI patients.

Tumor necrosis factor alpha promotes the expression of immunosuppressive proteins and enhances the cell growth in a human bone marrow-derived stem cell culture.

Mesenchymal stem cells (MSCs) are widely used in experimental treatments for various conditions that involve normal tissue regeneration via inflammatory repair. It is known that MSCs can secrete multiple soluble factors and suppress inflammation. Even though the effect of MSCs on inflammation has been extensively studied, the effect of inflammation on MSCs is poorly understood. One of the major cytokines released at the site of inflammation is tumor necrosis factor alpha (TNF-α) which is known to induce MSC invasion and proliferation. Therefore, we wanted to test the effects of TNF-α exposure on MSCs derived from human bone marrow. We found, as expected, that cell proliferation was significantly enhanced during TNF-α exposure. However, according to the cell surface marker analysis, the intensity of several antigens in the minimum criteria panel for MSCs proposed by International Society of Cellular Therapy (ISCT) was decreased dramatically, and in certain cases, the criteria for MSCs were not fulfilled. In addition, TNF-α exposure resulted in a significant but transient increase in human leukocyte antigen and CD54 expression. Additional proteomic analysis by two-dimensional difference gel electrophoresis and mass spectrometry revealed three proteins whose expression levels decreased and 8 proteins whose expression levels increased significantly during TNF-α exposure. The majority of these proteins could be linked to immunosuppressive and signalling pathways. These results strongly support reactive and immunosuppressive activation of MSCs during TNF-α exposure, which might influence MSC differentiation stage and capacity.

Leisure time emotional excitement increases endothelin-1 and interleukin-6 in cardiac patients.

OBJECTIVES. Emotional excitement may trigger serious cardiovascular (CV) events. Our objective was to compare the changes in potential surrogate markers of CV events in patients with coronary artery disease (CAD) during emotional excitement and exercise. DESIGN. Fifty-three enthusiastic ice-hockey spectators with stable CAD attended the Finnish national ice-hockey play-off matches and a maximal bicycle exercise. Plasma catecholamines, endothelin-1, interleukin-6, and markers of platelet activation and blood coagulation were determined before and during the match and before and after the exercise. RESULTS. Plasma endothelin-1 (2.82 ± 0.21 vs. 2.94 ± 0.25 pg/mL, p < 0.0001), noradrenaline (4.38 ± 1.79 vs. 4.77 ± 1.75 nmol/L, p = 0.009) and interleukin-6 (2.04 ± 1.98 vs. 2.90 ± 2.41 pg/mL, p < 0.0001) increased during the match, but markers of platelet activation and coagulation remained unchanged. Endothelin-1 did not change during exercise (2.73 ± 0.17 vs. 2.72 ± 0.19 pg/mL, p = 0.593) but noradrenaline (2.70 ± 1.08 vs.10.6 ± 5.5 nmol/L), adrenaline (0.23 ± 0.13 vs. 0.52 ± 0.37 nmol/L), interleukin-6 (1.77 ± 1.59 vs. 2.43 ± 1.78 pg/mL) and markers of platelet activation and blood coagulation increased significantly (p < 0.0001 for all). CONCLUSIONS. The responses of surrogate markers of acute CV events to emotional excitement and physical exercise are partly different. Emotional excitement causes concomitant increases in markers reflecting vulnerability to atherosclerotic plaque complications while physical exercise causes more prominent changes in markers of coagulation.

Biomarkers as predictors of sudden cardiac death in coronary artery disease patients with preserved left ventricular function (ARTEMIS study).

AIMS: Biomarkers have shown promising results in risk assessment of cardiovascular events. Their role in predicting the risk of sudden cardiac death (SCD) is not well established. We tested the performance of several biomarkers in risk assessment for SCD in patients with coronary artery disease (CAD) and preserved left ventricular function. METHODS AND RESULTS: The study population consisted of 1,946 CAD patients (68% male; mean age 66.9±8.6 yrs; type 2 diabetes (T2D) 43%) enrolled in the ARTEMIS study. The study subjects underwent examinations with echocardiography and measurement of several biomarkers. The primary endpoint of the study was SCD. During the mean follow up of 76±20 months 50 patients experienced SCD. Elevated high sensitive CRP (hs-CRP, p = 0.001), soluble ST2 (sST2, p<0.001), B-type natriuretic peptide (BNP, p<0.001), and highly sensitive TroponinT (hs-TnT, p<0.001) predicted the occurrence of SCD in univariate analysis. Using the optimal cutoff points, elevated sST2 (≥27.45ng/mL; hazard ratio [HR] 2.7; 95%CI 1.4-5.1, p = 0.003) and hs-TnT (≥15 ng/mL; HR 2.9; 95% CI 1.5-5.6, p = 0.002) were the strongest predictors of SCD followed by hs-CRP (HR 2.4; 95% CI 1.3-4.4, p = 0.004) and BNP (HR 1.9; 95% CI 1.0-3.7, p = 0.046) in adjusted analysis. Combination of elevated hs-TnT and sST2 resulted in adjusted HR of 6.4 (95% CI 2.6-15.5, p<0.001). CONCLUSION: Elevated sST2 and hs-TnT predict the occurrence of SCD among patients with CAD and preserved left ventricular function. The association between sST2, hs-TnT and SCD may be explained by an ongoing myocardial apoptosis followed by fibrosis leading to vulnerability to malignant arrhythmias.

Usefulness of Highly Sensitive Troponin as a Predictor of Short-Term Outcome in Patients With Diabetes Mellitus and Stable Coronary Artery Disease (from the ARTEMIS Study).

The aim of this study was to test the hypothesis that novel biomarkers may predict cardiac events in diabetic patients with stable coronary artery disease (CAD). Serum levels of highly sensitive troponin T (hs-TnT), B-type natriuretic peptide, highly sensitive C-reactive protein (hs-CRP), galectin-3, and soluble suppressor of tumorigenicity-2 (sST2) were analyzed in 1,137 patients with CAD and with type 2 diabetes, impaired glucose tolerance, or fasting glycaemia (diabetic group) and in 649 patients with normal glucose state. Cardiac death or hospitalization for congestive heart failure was the major end point during the follow-up of 2 years. Forty patients in the diabetic group (3.5%) and 9 patients in the nondiabetic group (1.4%) reached the primary end point. High hs-TnT level (≥14 ng/l) was the strongest predictor of the primary end point with hazard ratio of 24.5 (95% confidence interval 8.7 to 69.0; p <0.001) and remained so when adjusted for clinical variables, ejection fraction, renal, lipid, and glycemic status and other biomarkers (hazard ratio 9.9, 95% confidence interval 3.2 to 30.8; p <0.001). In the multivariate model, hs-CRP, B-type natriuretic peptide, and sST2 also predicted the primary end point in the diabetic group (p <0.01 for all). Only sST2 (p <0.001) and hs-CRP (p = 0.02) predicted the primary end point in nondiabetic group. The inclusion of hs-TnT in the model significantly improved discrimination (integrated discrimination improvement 0.050) and reclassification of the patients (net reclassification index 0.21). In conclusion, hs-TnT is a strong predictor of cardiac death or hospitalization for heart failure independently from traditional risk markers or other biomarkers in diabetic patients with stable CAD.

Bone Marrow Mononuclear Cell Transplantation Restores Inflammatory Balance of Cytokines after ST Segment Elevation Myocardial Infarction.

BACKGROUND: Acute myocardial infarction (AMI) launches an inflammatory response and a repair process to compensate cardiac function. During this process, the balance between proinflammatory and anti-inflammatory cytokines is important for optimal cardiac repair. Stem cell transplantation after AMI improves tissue repair and increases the ventricular ejection fraction. Here, we studied in detail the acute effect of bone marrow mononuclear cell (BMMNC) transplantation on proinflammatory and anti-inflammatory cytokines in patients with ST segment elevation myocardial infarction (STEMI). METHODS: Patients with STEMI treated with thrombolysis followed by percutaneous coronary intervention (PCI) were randomly assigned to receive either BMMNC or saline as an intracoronary injection. Cardiac function was evaluated by left ventricle angiogram during the PCI and again after 6 months. The concentrations of 27 cytokines were measured from plasma samples up to 4 days after the PCI and the intracoronary injection. RESULTS: Twenty-six patients (control group, n = 12; BMMNC group, n = 14) from the previously reported FINCELL study (n = 80) were included to this study. At day 2, the change in the proinflammatory cytokines correlated with the change in the anti-inflammatory cytokines in both groups (Kendall's tau, control 0.6; BMMNC 0.7). At day 4, the correlation had completely disappeared in the control group but was preserved in the BMMNC group (Kendall's tau, control 0.3; BMMNC 0.7). CONCLUSIONS: BMMNC transplantation is associated with preserved balance between pro- and anti-inflammatory cytokines after STEMI in PCI-treated patients. This may partly explain the favorable effect of stem cell transplantation after AMI.

Serum PINP, PIIINP, galectin-3, and ST2 as surrogates of myocardial fibrosis and echocardiographic left venticular diastolic filling properties.

OBJECTIVES AND BACKGROUND: Serum biomarkers have been proposed to reflect fibrosis of several human tissues, but their specific role in the detection of myocardial fibrosis has not been well-established. We studied the association between N-terminal propeptide of type I and III procollagen (PINP, PIIINP, respectively), galectin-3 (gal-3), soluble ST2 (ST2), and myocardial fibrosis measured by late gadolinium enhanced cardiac magnetic resonance imaging (LGE CMR) and their relation to left ventricular diastolic filling properties measured by tissue Doppler echocardiography (E/e') in patients with stable coronary artery disease (CAD). METHODS AND RESULTS: We determined the PINP, PIIINP, gal-3, and ST2 serum levels and performed LGE CMR and echocardiography on 63 patients with stable CAD without a history of prior myocardial infarction. Myocardial late gadolinium enhancement T1 relaxation time was defined as a specific marker of myocardial fibrosis. ST2, PINP, and PIIINP did not have a significant correlation with the post-LGE T1 relaxation time tertiles (NS for all), but the lowest post-LGE T1 relaxation time tertile had significantly higher gal-3 values than the other two tertiles (p = 0.002 and 0.002) and higher E/é-values (p = 0.009) compared to the highest T1 relaxation time tertile. ST2 (p = 0.025 and 0.029), gal-3 (p = 0.003 and < 0.001) and PIIINP (p = 0.001 and 0.007) levels were also significantly higher in the highest E/é tertile, compared to the other two tertiles. CONCLUSIONS: Elevated serum levels of gal-3 reflect the degree of myocardial fibrosis assessed by LGE CMR. Gal-3, ST2, and PIIINP are also elevated in patients with impaired LV diastolic function, suggesting that these biomarkers are useful surrogates of structural and functional abnormality of the myocardium.

Functional consequences of perturbed CXCL12 signal processing: analyses of immature hematopoiesis in GRK6-deficient mice.

Hematopoietic stem and progenitor cells (HSPCs) reside in bone marrow (BM) in an environment rich in CXCL12, the ligand for CXCR4, which is constitutively expressed on all immature hematopoietic cells in BM. This ligand-receptor pair critically controls HSPC retention and (relative) quiescence in BM. Interestingly, in a chemokine-abundant environment, CXCR4 surface expression and CXCL12 sensitivity of BM-residing HSPCs are continuously maintained. The mechanisms underlying this peculiar pattern of G-protein signal integration by BM-HSPCs are unknown. G-protein receptor kinases (GRKs) control receptor function by phosphorylating the intracellular domains upon ligand-induced activation, which results in receptor internalization and transient refractoriness. Using, therefore, a GRK6-deficient (GRK6(-/-)) mouse, we sought to address how perturbed ligand-induced CXCR4 (in)activation affects HSPC behavior in vitro and in vivo. In vitro, GRK6(-/-) HSPCs were characterized by hyper-responsiveness to CXCL12, as expected. In vivo, GRK6(-/-) immature hematopoiesis was characterized by a marked expansion of immature hematopoiesis in spleens and a modest repopulation defect in serial competitive transplantation. Enforced mobilization with granulocyte colony-stimulating factor (G-CSF) and AMD3100 was normal, as was hematopoietic regeneration after noncompetitive transplantation or pharmacological myelosuppression. These observations illustrate that GRK-mediated restriction of CXCR4 signal input after ligand engagement is largely dispensable for BM-resident HSPCs, which may explain how continuous CXCL12 responsiveness of BM-HSPCs can be maintained.

Physiological responses to emotional excitement in healthy subjects and patients with coronary artery disease.

Emotional excitement may trigger cardiovascular (CV) events, particularly in patients with coronary artery disease (CAD). Our aim was to compare changes in various biomarkers in CAD patients and age-matched healthy male subjects during "real-life" emotional excitement. Enthusiastic male ice hockey spectators (CAD n = 18, healthy subjects n = 16) attended Finnish national ice hockey play-off matches. Heart rate variability, plasma catecholamines, endothelin-1 (ET-1) and interleukin-6 (IL-6) were determined at the baseline and during the match. A significantly more marked increase in both ET-1 and IL-6 was observed in CAD patients compared with healthy subjects during the match (time × group interaction p = 0.009 and p = 0.018 for ET-1 and IL-6, respectively). The high-frequency power of R-R intervals decreased in CAD patients (p<0.001) but did not change in healthy subjects (p = ns, time × group interaction p<0.001). Changes in adrenaline and noradrenaline did not differ between the groups. Emotional excitement causes more marked increases of markers of vasoconstriction and acute inflammation and withdrawal of cardiac vagal regulation in patients with CAD.

Cardiac Function, Perfusion, Metabolism, and Innervation following Autologous Stem Cell Therapy for Acute ST-Elevation Myocardial Infarction. A FINCELL-INSIGHT Sub-Study with PET and MRI.

PURPOSE: Beneficial mechanisms of bone marrow cell (BMC) therapy for acute ST-segment elevation myocardial infarct (STEMI) are largely unknown in humans. Therefore, we evaluated the feasibility of serial positron emission tomography (PET) and MRI studies to provide insight into the effects of BMCs on the healing process of ischemic myocardial damage. METHODS: Nineteen patients with successful primary reteplase thrombolysis (mean 2.4 h after symptoms) for STEMI were randomized for BMC therapy (2.9 × 10(6) CD34+ cells) or placebo after bone marrow aspiration in a double-blind, multi-center study. Three days post-MI, coronary angioplasty, and paclitaxel eluting stent implantation preceded either BMC or placebo therapy. Cardiac PET and MRI studies were performed 7-12 days after therapies and repeated after 6 months, and images were analyzed at a central core laboratory. RESULTS: In BMC-treated patients, there was a decrease in [(11)C]-HED defect size (-4.9 ± 4.0 vs. -1.6 ± 2.2%, p = 0.08) and an increase in [(18)F]-FDG uptake in the infarct area at risk (0.06 ± 0.09 vs. -0.05 ± 0.16, p = 0.07) compared to controls, as well as less left ventricular dilatation (-4.4 ± 13.3 vs. 8.0 ± 16.7 mL/m(2), p = 0.12) at 6 months follow-up. However, BMC treatment was inferior to placebo in terms of changes in rest perfusion in the area at risk (-0.09 ± 0.17 vs. 0.10 ± 0.17, p = 0.03) and infarct size (0.4 ± 4.2 vs. -5.1 ± 5.9 g, p = 0.047), and no effect was observed on ejection fraction (p = 0.37). CONCLUSION: After the acute phase of STEMI, BMC therapy showed only minor trends of long-term benefit in patients with rapid successful thrombolysis. There was a trend of more decrease in innervation defect size and enhanced glucose metabolism in the infarct-related myocardium and also a trend of less ventricular dilatation in the BMC-treated group compared to placebo. However, no consistently better outcome was observed in the BMC-treated group compared to placebo.

Effects of intracoronary injection of autologous bone marrow-derived stem cells on natriuretic peptides and inflammatory markers in patients with acute ST-elevation myocardial infarction.

BACKGROUND: Intracoronary administration of autologous bone marrow stem cells (BMC) has been shown to result in a subtle improvement of global left ventricular ejection fraction after ST-elevation myocardial infarction (STEMI), but the overall benefits of BMC therapy are still unclear. We studied the influence of intracoronary injections of BMC on levels of natriuretic peptides and inflammatory mediators, which are well established prognostic biomarkers, in patients with STEMI. METHODS: In this randomized, double-blind study, consecutive patients with an acute STEMI treated with thrombolysis followed by PCI 2-6 days after STEMI, were randomly assigned to receive either intracoronary BMC or placebo medium into the infarct-related artery. Blood samples were drawn for biochemical determinations. RESULTS: From baseline to 6 months, there was a significant decrease in the levels of N-terminal probrain natriuretic peptide (NT-proBNP), interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) in the whole patient population (P < 0.001 for all). However, no difference was observed between the BMC group (n = 39) and the placebo group (n = 39) in the change of the levels of NT-proANP (median -54 vs. +112 pmol/L), NT-proBNP (-88 vs. -115 pmol/L) or inflammatory markers IL-6 (-3.86 vs. -5.61 pg/mL), hsCRP (-20.29 vs. -22.36 mg/L) and tumor necrosis factor α (-0.12 vs. -0.80 pg/mL) between baseline and 6 months. CONCLUSION: Intracoronary BMC therapy does not appear to exert any significant effects on the secretion of natriuretic peptides or inflammatory biomarkers in STEMI patients.

Determinants of functional recovery after myocardial infarction of patients treated with bone marrow-derived stem cells after thrombolytic therapy.

OBJECTIVE: To assess the determinants of functional recovery in patients with ST-elevation myocardial infarction (STEMI) treated initially with thrombolysis, followed by percutaneous coronary intervention and intracoronary injection of bone marrow-derived stem cells (BMC). DESIGN: A randomised, placebo-controlled, double-blind study (substudy of FINCELL). SETTING: Two tertiary cardiac centres. PARTICIPANTS: 78 patients with STEMI randomly assigned to receive either intracoronary BMC (n=39) or placebo (n=39) into the infarct-related artery. INTERVENTIONS: Thrombolysis a few hours after symptom onset, percutaneous coronary intervention and intracoronary injection of BMC 2-6 days later. MAIN OUTCOME MEASURES: Efficacy of the BMC treatment was assessed by measurement of the change of global left ventricular ejection fraction (LVEF) from baseline to 6 months after STEMI. Various predefined variables (eg, the levels of certain natriuretic peptides and inflammatory cytokines) were analysed as determinants of improvement of LVEF. RESULTS: In the BMC group, the most powerful determinant of the change in LVEF was the baseline LVEF (r=-0.58, p<0.001). Patients with baseline LVEF at or below the median (< or = 62.5%) experienced a more marked improvement in LVEF (+12.7 + or - 12.5 %units, p<0.001) than those above the median (-0.8 + or - 6.3 %units, p=0.10). Elevated N-terminal probrain natriuretic peptide (p<0.001) and N-terminal proatrial natriuretic peptide (p=0.052) levels were also associated with improvement in LVEF in the BMC group but not in the placebo group. CONCLUSIONS: The global LVEF recovers most significantly after intracoronary infusion of BMC in patients with the most severe impairment of LVEF on admission. The baseline levels of natriuretic peptides seem also to be associated with LVEF recovery after BMC treatment. Trial registration ClinicalTrials.gov number, NCT00363324.