Short-term effects of dapagliflozin on maximal functional capacity in heart failure with reduced ejection fraction (DAPA-VO2 ): a randomized clinical trial.

AIMS: This study aimed to evaluate the effect of dapagliflozin on 1 and 3-month maximal functional capacity in patients with stable heart failure with reduced ejection fraction (HFrEF). METHODS AND RESULTS: In this multicentre, randomized, double-blind clinical trial, 90 stable patients with HFrEF were randomly assigned to receive either dapagliflozin (n = 45) or placebo (n = 45). The primary outcome was a change in peak oxygen consumption (peakVO2 ) at 1 and 3 months. Secondary endpoints were changes at 1 and 3 months in 6-min walk test (6MWT) distance, quality of life (Minnesota Living with Heart Failure Questionnaire [MLHFQ]), and echocardiographic parameters (diastolic function, left chamber volumes, and left ventricular ejection fraction). We used linear mixed regression analysis to compare endpoint changes. Estimates were adjusted for multiple comparisons. The mean age was 67.1 ± 10.7 years, 69 (76.7%) were men, 29 (32.2%) had type 2 diabetes, and 80 (88.9%) were in New York Heart Association class II. Baseline means of peakVO2 , 6MWT and MLHFQ were 13.2 ± 3.5 ml/kg/min, 363 ± 110 m, and 23.1 ± 16.2, respectively. The median (25th-75th percentile) of N-terminal pro-brain natriuretic peptide was 1221 pg/ml (889-2100). Most patients were on treatment with sacubitril/valsartan (88.9%), beta-blockers (91.1%), and mineralocorticoid receptor antagonists (74.4%). PeakVO2 significantly increased in patients on treatment with dapagliflozin (1 month: +Δ 1.09 ml/kg/min, 95% confidence interval [CI] 0.14-2.04; p = 0.021, and 3 months: +Δ 1.06 ml/kg/min, 95% CI 0.07-2.04; p = 0.032). Similar positive findings were found when evaluating changes from baseline. No significant differences were observed in secondary endpoints. CONCLUSIONS: Among patients with stable HFrEF, dapagliflozin resulted in a significant improvement in peakVO2 at 1 and 3 months. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04197635.

Incidence, Treatment and Clinical Impact of Iron Deficiency in Chronic Heart Failure: A Longitudinal Analysis.

In patients with heart failure (HF), iron deficiency (ID) is a well-recognized therapeutic target; information about its incidence, patterns of iron repletion, and clinical impact is scarce. This single-centre longitudinal cohort study assessed the rates of ID testing and diagnosis in patients with stable HF, patterns of treatment with intravenous iron, and clinical impact of intravenous iron on HF rehospitalization risk. We included 711 consecutive outpatients (4400 visits) with stable chronic HF from 2014 to 2019 (median [interquartile range] visits per patient: 2 [2−7]. ID was defined as serum ferritin <100 µg/L, or 100−299 µg/L with transferrin saturation (TSAT) < 20%. During a median follow-up of 2.20 (1.11−3.78) years, ferritin and TSAT were measured at 2230 (50.7%) and 2183 visits (49.6%), respectively. ID was found at 846 (37.9%) visits, with ferritin and TSAT available (2230/4400), and intravenous iron was administered at 321/4400 (7.3%) visits; 233 (32.8%) patients received intravenous iron during follow-up. After multivariate analyses, iron repletion at any time during follow-up was associated with a lower risk of recurrent HF hospitalization (hazard ratio [HR] = 0.50, 95% confidence interval [CI] = 0.28−0.88; p = 0.016). Thus, ID was a frequent finding in patients with HF, and its repletion reduced the risk of recurrent HF hospitalizations.

Iron deficiency and short-term adverse events in patients with decompensated heart failure.

BACKGROUND: For patients with heart failure (HF), iron deficiency (ID) is a common therapeutic target. However, little is known about the utility of transferrin saturation (TSAT) or serum ferritin for risk stratification in decompensated HF (DHF) or the European Society of Cardiology's (ESC) current definition of ID (ferritin < 100 µg/L or TSAT < 20% if ferritin is 100-299 µg/L). We evaluated the association between these potential markers of ID and the risk of 30-day readmission for HF or death in patients with DHF. METHODS: We retrospectively included 1701 patients from a multicenter registry of DHF. Serum ferritin and TSAT were evaluated 24-72 h after hospital admission, and multivariable Cox regression was used to assess their association with the composite endpoint. RESULTS: Participants' median (quartiles) age was 76 (68-82) years, 43.8% were women, and 51.7% had a left ventricular ejection fraction > 50%. Medians for NT-proBNP, TSAT, and ferritin were 4067 pg/mL (1900-8764), 14.1% (9.0-20.3), and 103 ug/L (54-202), respectively. According to the current ESC definition, 1,246 (73.3%) patients had ID. By day 30, there were 177 (10.4%) events (95 deaths and 85 HF readmission). After multivariable adjustment, lower TSAT was associated with outcome (p = 0.009) but serum ferritin was not (HR 1.00; 95% confidence interval 0.99-1.00, p = 0.347). CONCLUSIONS: Lower TSAT, but not ferritin, was associated with a higher risk of short-term events in patients with DHF. Further research is needed to confirm these findings and the utility of serum ferritin as a marker of ID in DHF.

Alveolar Type II Cells or Mesenchymal Stem Cells: Comparison of Two Different Cell Therapies for the Treatment of Acute Lung Injury in Rats.

The use of cell therapies has recently increased for the treatment of pulmonary diseases. Mesenchymal stem/stromal cells (MSCs) and alveolar type II cells (ATII) are the main cell-based therapies used for the treatment of acute respiratory distress syndrome (ARDS). Many pre-clinical studies have shown that both therapies generate positive outcomes; however, the differences in the efficiency of MSCs or ATII for reducing lung damage remains to be studied. We compared the potential of both cell therapies, administering them using the same route and dose and equal time points in a sustained acute lung injury (ALI) model. We found that the MSCs and ATII cells have similar therapeutic effects when we tested them in a hydrochloric acid and lipopolysaccharide (HCl-LPS) two-hit ALI model. Both therapies were able to reduce proinflammatory cytokines, decrease neutrophil infiltration, reduce permeability, and moderate hemorrhage and interstitial edema. Although MSCs and ATII cells have been described as targeting different cellular and molecular mechanisms, our data indicates that both cell therapies are successful for the treatment of ALI, with similar beneficial results. Understanding direct cell crosstalk and the factors released from each cell will open the door to more accurate drugs being able to target specific pathways and offer new curative options for ARDS.

Induced pluripotent stem cell-derived lung alveolar epithelial type II cells reduce damage in bleomycin-induced lung fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis is a chronic, progressive, and severe disease with a limited response to currently available therapies. Epithelial cell injury and failure of appropriate healing or regeneration are central to the pathogenesis of idiopathic pulmonary fibrosis. The purpose of this study is to investigate whether intratracheal transplantation of alveolar type II-like cells differentiated from induced pluripotent stem cells can stop and reverse the fibrotic process in an experimental model of bleomycin-induced lung fibrosis in rats. METHODS: Human induced pluripotent stem cells were differentiated to alveolar type II-like cells and characterized. Lung fibrosis was induced in rats by a single intratracheal instillation of bleomycin. Animals were transplanted with human induced pluripotent stem cells differentiated to alveolar type II-like cells at a dose of 3 × 106 cells/animal 15 days after endotracheal bleomycin instillation when the animal lungs were already fibrotic. Animals were sacrificed 21 days after the induction of lung fibrosis. Lung fibrosis was assessed by hydroxiprolin content, histologic studies, and the expression of transforming growth factor-ß and α-smooth muscle actin. RESULTS: Cell transplantation of alveolar type II-like cells differentiated from induced pluripotent stem cells can significantly reduce pulmonary fibrosis and improve lung alveolar structure, once fibrosis has already formed. This is associated with the inhibition of transforming growth factor-ß and α-smooth muscle actin in the damaged rat lung tissue. CONCLUSION: To our knowledge, this is the first data to demonstrate that at the fibrotic stage of the disease, intratracheal transplantation of human induced pluripotent differentiated to alveolar type II-like cells halts and reverses fibrosis.

Iron deficiency and long-term mortality in elderly patients with acute coronary syndrome.

AIM: We evaluated the relationship between iron deficiency (ID) and long-term mortality risk in elderly patients with acute coronary syndrome (ACS). METHODS: In this prospective observational study, we included 252 patients older than 65 years with ACS. Transferrin saturation (TSAT) and ferritin were collected before discharge. RESULTS: Mean age, hemoglobin and GRACE score were 78 ± 7 years, 12.4 ± 1.8 g/dl and 138.8 ± 25.3, respectively, 112(44.4%) patients were women, and 151(59.9%) presented ID. During the follow-up, 121 (48%) patients died. Mortality rates among TSAT quartiles were: 2.38, 1.60, 0.90 and 0.95 × 10 person-years for Q1TSAT to Q4TSAT, respectively (p < 0.001) and did not differ across ferritin quartiles (p = 0.601), whereas ID definition was borderline associated (p = 0.060). Adjusted TSAT levels remained inverse, nonlinearly associated with long-term mortality risk (p < 0.001), with an exponential increased-risk from values about 20% and below. CONCLUSION: Lower TSAT levels were independently associated with increased mortality risk in these patients.

Left ventricular ejection fraction recovery in patients with heart failure treated with intravenous iron: a pilot study.

AIMS: In patients with heart failure with reduced ejection fraction (HFrEF) and iron deficiency, treatment with intravenous iron has shown a clinical improvement regardless of anaemic status. Cardiac magnetic resonance (CMR) T2* sequence has shown a potential utility for evaluating myocardial iron deficiency. We aimed to evaluate whether T2* sequence significantly changes after ferric carboximaltose (FCM) administration, and if such changes correlate with changes in left ventricle ejection fraction (LVEF). METHODS AND RESULTS: In this pilot study, we included eight patients with chronic symptomatic (New York Heart Association II-III) HFrEF and iron deficiency. A CMR, including T2* analysis, was performed before and at a median of 43 days (interquartile range = 35-48) after intravenous FCM administration. Pearson or Spearman correlation coefficient (r) was used for bivariate contrast as appropriate. A partial correlation analysis was performed between ΔLVEF and ΔT2* while controlling for anaemia status at baseline. Anaemia was present in half of patients. After FCM administration, T2* decreased from a median of 39.5 (35.9-48) to 32 ms (32-34.5), P = 0.012. Simultaneously, a borderline increase in median of LVEF [40% (36-44.5) to 48.5% (38.5-53), P = 0.091] was registered. In a bivariate correlational analysis, ΔT2* was highly correlated with ΔLVEF (r = -0.747, P = 0.033). After controlling for anaemia at baseline, the association between ΔT2* and ΔLVEF persisted [r(partial): -0.865, R2(partial): 0.748, P = 0.012]. A median regression analysis backed-up these findings. CONCLUSIONS: In a small sample of patients with HFrEF and iron deficiency, myocardial iron repletion assessed by CMR was associated to left ventricular remodelling. Further studies are warranted.

Iron deficiency and risk of early readmission following a hospitalization for acute heart failure.

AIMS: Early rehospitalization after an episode of acute heart failure (AHF) remains excessively high and its prediction a contemporary challenge. Iron deficiency (ID) is a frequent finding in AHF, but its prognostic implications remain unclear. We sought to evaluate the association between ID and risk of 30-day readmission in an unselected cohort of patients discharged for AHF. METHODS AND RESULTS: Serum ferritin and transferrin saturation (TSAT) were measured before discharge in 626 consecutive patients with AHF in a single teaching centre. ID was defined as serum ferritin <100 µg/L (absolute ID) or ferritin 100-299 µg/L with a TSAT <20% (functional ID). Cox regression adapted for competing events was used to determine the association between ID and the risk of 30-day readmissions. Mean age was 73.4 ± 10.4 years, 48% were females, and 52.1% showed an LVEF >50%. ID was identified in 463 patients (74%): 302 (48.2%) as absolute ID and 161 (25.7%) as functional ID. At 30-day post-discharge, 20 (3.2%) patients died and 103 (16.5%) were readmitted. Patients with absolute ID showed an increased rate of readmission compared with those with functional ID and no ID (19.9, 13, and 13.5%, respectively, P = 0.005). In a multivariate setting, absolute ID remained associated with higher risk of readmission [hazard ratio (HR) 1.72; 95% confidence interval (CI) 1.13-2.60, P = 0.011]. Compared with patients without ID, functional ID was not related to the risk of readmission (HR 0.87; 95% CI 0.46-1.62, P = 0.652). CONCLUSION: In patients with AHF, absolute ID, but not functional ID, was associated with an increased risk of early readmission.

Safety and Tolerability of Alveolar Type II Cell Transplantation in Idiopathic Pulmonary Fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease with limited response to currently available therapies. Alveolar type II (ATII) cells act as progenitor cells in the adult lung, contributing to alveolar repair during pulmonary injury. However, in IPF, ATII cells die and are replaced by fibroblasts and myofibroblasts. In previous preclinical studies, we demonstrated that ATII-cell intratracheal transplantation was able to reduce pulmonary fibrosis. The main objective of this study was to investigate the safety and tolerability of ATII-cell intratracheal transplantation in patients with IPF. METHODS: We enrolled 16 patients with moderate and progressive IPF who underwent ATII-cell intratracheal transplantation through fiberoptic bronchoscopy. We evaluated the safety and tolerability of ATII-cell transplantation by assessing the emergent adverse side effects that appeared within 12 months. Moreover, pulmonary function, respiratory symptoms, and disease extent during 12 months of follow-up were evaluated. RESULTS: No significant adverse events were associated with the ATII-cell intratracheal transplantation. After 12 months of follow-up, there was no deterioration in pulmonary function, respiratory symptoms, or disease extent. CONCLUSIONS: Our results support the hypothesis that ATII-cell intratracheal transplantation is safe and well tolerated in patients with IPF. This study opens the door to designing a clinical trial to elucidate the potential beneficial effects of ATII-cell therapy in IPF.

Alveolar type II cell transplantation restores pulmonary surfactant protein levels in lung fibrosis.

BACKGROUND: Alveolar Type II cell transplantation has been proposed as a cell therapy for the treatment of idiopathic pulmonary fibrosis. Its long-term benefits include repair of lung fibrosis, but its success partly depends on the restoration of lung homeostasis. Our aim was to evaluate surfactant protein restoration after alveolar Type II cell transplantation in an experimental model of bleomycin-induced lung fibrosis in rats. METHODS: Lung fibrosis was induced by intratracheal instillation of bleomycin. Alveolar Type II cells were obtained from healthy animals and transplanted 14 days after bleomycin was administered. Furthermore, one group transplanted with alveolar macrophages and another group treated with surfactant were established to evaluate the specificity of the alveolar Type II cell transplantation. The animals were euthanized at 21 days after bleomycin instillation. Lung fibrosis was confirmed by a histologic study and an evaluation of the hydroxyproline content. Changes in surfactant proteins were evaluated by mRNA expression, Western blot and immunofluorescence studies. RESULTS: The group with alveolar Type II cell transplantation was the only one to show a reduction in the degree of lung fibrosis and a complete recovery to normal levels of surfactant proteins. CONCLUSION: One of the mechanisms involved in the beneficial effect of alveolar Type II cell transplantation is restoration of lung surfactant protein levels, which is required for proper respiratory function.

Pirfenidone for the treatment of idiopathic pulmonary fibrosis.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive and lethal fibrosing interstitial pneumonia. The median survival from the onset of the symptoms is 2.8 - 4.2 years and the 5-year survival rate is 20%. Its poor prognosis, combined with the scarcity of treatment options, provides a strong rationale for the development of novel therapeutic strategies. During the past decade there has been a huge rise in clinical trials with anti-fibrotic drugs, although only pirfenidone (Esbriet) has shown a beneficial effect. AREAS COVERED: This article reviews the medical literature on the effectiveness and safety of pirfenidone in IPF, by means of a PubMed search from 1995 to present, completed with some data on file from the manufacturer. EXPERT OPINION: Pirfenidone is the only anti-fibrotic drug approved for the treatment of IPF. Pirfenidone provides a meaningful clinical effect on reductions in the decrease in forced vital capacity (FVC), six-minute walk test (6MWT) distance and mortality, and it improves the progression-free survival in IPF patients with mild-to-moderate disease. Pirfenidone is well tolerated, with the most common side-effects being gastrointestinal discomfort and photosensitivity. Pirfenidone has a favorable benefit-risk profile and represents a suitable treatment option for patients with mild-to-moderate IPF.

Guidelines for the diagnosis and treatment of idiopathic pulmonary fibrosis. Sociedad Española de Neumología y Cirugía Torácica (SEPAR) Research Group on Diffuse Pulmonary Diseases.

Idiopathic pulmonary fibrosis is defined as a chronic fibrosing interstitial pneumonia limited to the lung, of unknown cause, with poor prognosis and few treatment options. In recent years there has been an increase in their prevalence, probably due to the optimization of diagnostic methods and increased life expectancy. The ATS/ERS Consensus (2000) established the diagnostic criteria and recommendations for the assessment of the disease course and treatment. Later studies have helped to redefine diagnostic criteria and treatment options. In 2011, an international consensus was published, establishing diagnostic criteria and new treatment strategies. These guidelines have been updated with the newest aspects of diagnosis and treatment of idiopathic pulmonary fibrosis. A level of evidence has been identified for the most relevant questions, particularly with regard to treatment options.

[Alveolar epithelial cell injury as an etiopathogenic factor in pulmonary fibrosis]. / La célula epitelial como factor etiopatogénico de la fibrosis pulmonar.

Idiopathic pulmonary fibrosis (IPF) is characterized by a progressive accumulation of extracellular matrix and an imbalance between profibrotic and antifibrotic mediators. In the last few years, understanding of the mechanisms of the biology of IPF has increased. One of the most significant discoveries is the finding that alveolar epithelial cell injury plays an important role in the pathogenesis of this disease. In this review, we describe some of the mechanisms involved in alveolar cell injury and their contribution to the development of IPF.

Biological consequences of oxygen desaturation and respiratory effort in an acute animal model of obstructive sleep apnea (OSA).

BACKGROUND: An animal model mimicking all the factors involved in obstructive sleep apnea (OSA) is useful for investigating mechanisms because the associated comorbidity usually present in such patients is an important limitation. AIM: To test the hypothesis that hypoxia/normoxia and respiratory effort have different effects on the induction of inflammatory response and endothelial dysfunction in an acute rat model of OSA. METHODS: Four groups of anesthetized rats were studied (n=8): (1) sham; (2) apnea: obstructions (15s each, 60/h, for 3h); (3) apnea+O(2): obstructions and breathing oxygen-enriched air to avoid hypoxia and (4) intermittent hypoxia/normoxia. Inflammatory and endothelial mediators were measured as outcomes along with NF-kappaB in the lung and diaphragm. RESULTS: TNF-alpha and IL-1beta significantly increased in all groups compared with sham. NF-kappaB in the lung was increased in apnea and hypoxia/normoxia groups, but not in apnea+O(2) group. In diaphragm tissue, NF-kappaB was only significant in apnea compared to sham. Significant differences were found in the ratio thromboxane-B2/6-keto-Prostaglandin-F1alpha between apnea and hypoxia/normoxia compared to sham but not in apnea+O(2). CONCLUSIONS: Oxygen desaturations and respiratory efforts play a role in the induction of systemic inflammation but only hypoxia/normoxia induces endothelial dysfunction. These data suggest a potential role for oxygen therapy in patients with OSA.

Intratracheal transplantation of alveolar type II cells reverses bleomycin-induced lung fibrosis.

RATIONALE: Transplantation of stem cells has been proposed as a strategy for repair of lung fibrosis. Nevertheless, many studies have yielded controversial results that currently limit the potential use of these cells as an efficient treatment. Alveolar type II cells are the progenitor cells of the pulmonary epithelium and usually proliferate after epithelial cell injury. During lung fibrosis, however, the altered regeneration process leads to uncontrolled fibroblast proliferation. OBJECTIVES: To investigate whether intratracheal transplantation of isolated alveolar type II cells can halt and reverse the fibrotic process in an experimental model of bleomycin-induced lung fibrosis in rats. METHODS: Lung fibrosis was induced in syngeneic female Lewis rats by a single intratracheal instillation of bleomycin (2.5 U/kg). Animals were transplanted with alveolar type II cells from male animals at a dose of 2.5 x 10(6) cells per animal 3, 7, and 15 days after endotracheal bleomycin instillation. Animals were killed 21 days after the induction of lung fibrosis. MEASUREMENTS AND MAIN RESULTS: Lung fibrosis was assessed by histologic study and determination of hydroxyproline content. Engraftment of transplanted cells was measured by real-time polymerase chain reaction for the Y chromosome and by fluorescence in situ hybridization for the Y chromosome. Transplantation of alveolar type II cells into damaged lung 3, 7, or 15 days after bleomycin instillation led to reduced collagen deposition, and reduction in the severity of pulmonary fibrosis. CONCLUSIONS: This study demonstrates the potential role of alveolar type II cell transplantation in designing future therapies for lung fibrosis.

Extravascular sources of lung angiotensin peptide synthesis in idiopathic pulmonary fibrosis.

Previous work from this laboratory demonstrated de novo synthesis of angiotensin (ANG) peptides by apoptotic pulmonary alveolar epithelial cells (AEC) and by lung myofibroblasts in vitro and in bleomycin-treated rats. To determine whether these same cell types also synthesize ANG peptides de novo within the fibrotic human lung in situ, we subjected paraffin sections of normal and fibrotic (idiopathic pulmonary fibrosis, IPF) human lung to immunohistochemistry (IHC) and in situ hybridization to detect ANG peptides and angiotensinogen (AGT) mRNA. These were analyzed both alone and in combination with cell-specific markers of AEC [monoclonal antibody (MAb) MNF-116] and myofibroblasts [alpha-smooth muscle actin (alpha-SMA) MAb] and an in situ DNA end labeling (ISEL) method to detect apoptosis. In normal human lung, IHC detected AGT protein in smooth muscle underlying normal bronchi and vessels, but not elsewhere. Real-time RT-PCR and Western blotting revealed that AGT mRNA and protein were 21-fold and 3.6-fold more abundant, respectively, in IPF lung biopsies relative to biopsies of normal human lung (both P < 0.05). In IPF lung, both AGT protein and mRNA were detected in AEC that double-labeled with MAb MNF-116 and with ISEL, suggesting AGT expression by apoptotic epithelia in situ. AGT protein and mRNA also colocalized to myofibroblast foci detected by alpha-SMA MAb, but AGT mRNA was not detected in smooth muscle. These data are consistent with earlier data from isolated human lung cells in vitro and bleomycin-induced rat lung fibrosis models, and they suggest that apoptotic AEC and myofibroblasts constitute key sources of locally derived ANG peptides in the IPF lung.