Effects of combined aerobic, resistance and inspiratory training in patients with pulmonary hypertension: A systematic review

BACKGROUND

Pulmonary hypertension (PH) is a serious progressive disorder of the modern world, characterized by endothelial dysfunction and impaired vasoreactivity. Patients with PH usually present exercise intolerance from the very early stages and reduced exercise capacity. Exercise training has been shown to have beneficial effects in patients with cardiovascular comorbidities. However, data regarding the effects of combined exercise training programs in patients with PH still remains limited.

AIM

To investigate the effects of combined exercise training programs on exercise capacity and quality of life in patients with PH.

METHODS

Our search included all available randomized controlled trials (RCTs) regarding combined aerobic, resistance and inspiratory training programs in patients with PH in 4 databases (Pubmed, PEDro, Embase, CINAHL) from 2012 to 2022. Five RCTs were included in the final analysis. Functional capacity, assessed by peak VO2 or 6-min walking test (6MWT), as well as quality of life, assessed by the SF-36 questionnaire, were set as the primary outcomes in our study.

RESULTS

Peak VO2 was measured in 4 out of the 5 RCTs while 6MWT was measured in all RCTs. Both indices of functional capacity were significantly increased in patients with PH who underwent combined exercise training compared to the controls in all of the included RCTs (P < 0.05). Quality of life was measured in 4 out of 5 RCTs. Although patients improved their quality of life in each group, however, only 2 RCTs demonstrated further improvement in patients performing combined training compared to controls.

CONCLUSION

By this systematic review, we have demonstrated that combined aerobic, resistance and inspiratory exercise training is safe and has beneficial effects on aerobic capacity and quality of life in patients with PH. Such exercise training regimen may be part of the therapeutic strategy of the syndrome.

The Effects of a Cardiac Rehabilitation Program on Endothelial Progenitor Cells and Inflammatory Profile in Patients with Chronic Heart Failure of Different Severity

Endothelial dysfunction and inflammation are common pathophysiological characteristics of chronic heart failure (CHF). Endothelial progenitor cells (EPCs) are recognized as useful markers of vascular damage and endothelial repair. The aim of this study was to investigate the effects of a cardiac rehabilitation program on EPCs and inflammatory profile in CHF patients of different severity. Forty-four patients with stable CHF underwent a 36-session cardiac rehabilitation program. They were separated into two different subgroups each time, according to the median peak VO2, predicted peak VO2, VE/VCO2 slope, and ejection fraction. EPCs, C-reactive protein (CRP), interleukin 6 (IL-6), interleukin 10 (IL-10), and vascular endothelial growth factor (VEGF) were measured. Flow cytometry was used for the quantification of EPCs. Mobilization of EPCs increased and the inflammatory profile improved within each severity group (p < 0.05) after the cardiac rehabilitation program, but there were no statistically significant differences between groups (p > 0.05). A 36-session cardiac rehabilitation program has similar beneficial effects on the mobilization of EPCs and on the inflammatory profile in patients with CHF of different severity.

International validation of the Metabolic Exercise test data combined with Cardiac and Kidney Indexes (MECKI) score in heart failure

AIMS

Current European heart failure (HF) guidelines suggest the use of risk score: among them, the Metabolic Exercise test data combined with Cardiac and Kidney Indexes (MECKI) score has demonstrated to be one of the most accurate. However, the risk scores are still poorly implemented in clinical practice, also due to the lack of strong evidence regarding their external validation in different populations. Thus, the current study was designed as an external validation test of the MECKI score in an international multicentre setting.

METHODS AND RESULTS

The study cohort consisted of patients diagnosed with HF with reduced ejection fraction (HFrEF) across international centres (not Italian), retrospectively recruited. Collected data included demographics, HF aetiology, laboratory testing, electrocardiogram (ECG), echocardiographic findings, and cardiopulmonary exercise testing (CPET) results as described in the original MECKI score publication. A total of 1042 patients across 8 international centres (7 European and 1 Asian) were included and followed up from 1998 till 2019. Patients were divided according to the calculated MECKI scores into three subgroups: (i) MECKI score <10%, (ii) 10-20%, and (iii) ≥ 20%. Survival analysis comparison among the three MECKI score subgroups showed a worse prognosis in patients with higher MECKI score value: median event-free survival times were 4396 days for MECKI score <10%, 3457 days for 10-20%, and 1022 days for ≥20% (P < 0.0001). Receiver operating characteristic (ROC) curves and area under the ROC curves (AUC) were like those reported in the original internal validation studies.

CONCLUSION

In patients diagnosed with HFrEF, the power of the MECKI score was confirmed in terms of prognosis and risk stratification, supporting its implementation as advised by the HF guidelines.

Incidence and peri-operative risk factors for development of acute kidney injury in patients after cardiac surgery: A prospective observational study

BACKGROUND

Patients admitted to intensive care unit (ICU) after cardiac surgery develop acute kidney injury (AKI) immediately post-operation. We hypothesized that AKI occurs mainly due to perioperative risk factors and may affect outcome.

AIM

To assess peri-operative risk factors for AKI post cardiac surgery and its relationship with clinical outcome.

METHODS

This was an observational single center, tertiary care setting study, which enrolled 206 consecutive patients, admitted to ICU after cardiac surgery. Patients were followed-up until ICU discharge or death, in order to determine the incidence of AKI, perioperative risk factors for AKI and its association with outcome. Univariate and multivariate logistic regression analysis was performed to assess predictor variables for AKI development.

RESULTS

After ICU admission, 55 patients (26.7%) developed AKI within 48 h. From the logistic regression analysis performed, high EuroScore II (OR: 1.18; 95%CI: 1.06-1.31, P = 0.003), white blood cells (WBC) pre-operatively (OR: 1.0; 95%CI: 1.0-1.0, P = 0.002) and history of chronic kidney disease (OR: 2.82; 95%CI: 1.195-6.65, P = 0.018) emerged as independent predictors of AKI among univariate predictors. AKI that developed AKI had longer duration of mechanical ventilation [1113 (777–2195) vs 714 (511–1020) min, P = 0.0001] and ICU length of stay [70 (28–129) vs 26 (21–51) h, P = 0.0001], higher rate of ICU-acquired weakness (16.4% vs 5.3%, P = 0.015), reintubation (10.9% vs 1.3%, P = 0.005), dialysis (7% vs 0%, P = 0.005), delirium (36.4% vs 23.8%, P = 0.001) and mortality (3.6% vs 0.7%, P = 0.046).

CONCLUSION

Patients present frequently with AKI after cardiac surgery. EuroScore II, WBC count and chronic kidney disease are independent predictors of AKI development. The occurrence of AKI is associated with poor outcome.

Effectiveness of high intensity interval training on cardiorespiratory fitness and endothelial function in type 2 diabetes: A systematic review

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic metabolic syndrome characterized by insulin resistance and hyperglycemia that may lead to endothelial dysfunction, reduced functional capacity and exercise intolerance. Regular aerobic exercise has been promoted as the most beneficial non-pharmacological treatment of cardiovascular diseases. High intensity interval training (HIIT) seems to be superior than moderate-intensity continuous training (MICT) in cardiovascular diseases by improving brachial artery flow-mediated dilation (FMD) and cardiorespiratory fitness to a greater extent. However, the beneficial effects of HIIT in patients with T2DM still remain under investigation and number of studies is limited.

AIM

To evaluate the effectiveness of high intensity interval training on cardiorespiratory fitness and endothelial function in patients with T2DM.

METHODS

We performed a search on PubMed, PEDro and CINAHL databases, selecting papers published between December 2012 and December 2022 and identified published randomized controlled trials (RCTs) in the English language that included community or outpatient exercise training programs in patients with T2DM. RCTs were assessed for methodological rigor and risk of bias via the Physiotherapy Evidence Database (PEDro). The primary outcome was peak VO₂ and the secondary outcome was endothelial function assessed either by FMD or other indices of microcirculation.

RESULTS

Twelve studies were included in our systematic review. The 12 RCTs resulted in 661 participants in total. HIIT was performed in 310 patients (46.8%), MICT to 271 and the rest 80 belonged to the control group. Peak VO₂ increased in 10 out of 12 studies after HIIT. Ten studies compared HIIT with other exercise regimens (MICT or strength endurance) and 4 of them demonstrated additional beneficial effects of HIIT over MICT or other exercise regimens. Moreover, 4 studies explored the effects of HIIT on endothelial function and FMD in T2DM patients. In 2 of them, HIIT further improved endothelial function compared to MICT and/or the control group while in the rest 2 studies no differences between HIIT and MICT were observed.

CONCLUSION

Regular aerobic exercise training has beneficial effects on cardiorespiratory fitness and endothelial function in T2DM patients. HIIT may be superior by improving these parameters to a greater extent than MICT.

Post Hospital Discharge Functional Recovery of Critical Illness Survivors. Systematic Review

Background

Millions of people face critical illnesses and need to be hospitalized in an Intensive Care Unit (ICU) annually worldwide. Despite the fact that survival rates of these patients have increased, they develop various cognitive, psychological and functional impairments. This study aims to investigate the significance of the recovery interventions following intensive care unit discharge, the effectiveness of the rehabilitative protocols and their possible deficits.

Methods

MEDLINE (PubMed) and Physiotherapy Evidence Database (PEDro) were searched for studies analyzing the recovery potentials post-ICU among adults, who spent at least 48 hours at the ICU. Methodological quality of the studies was assessed via PEDro Scale.

Results

Nine randomized controlled trials were included. These took place mainly at specialized rehabilitation gyms as well as patients home environments. Studies analyses showed that treatment group showed improvement in functional ability in relation to control group. Nevertheless, differences between two groups were not statistically significant (P<0.05). The majority of studies assessed cardiorespiratory endurance and muscular strength.

Conclusions

The included rehabilitation programs were determined to be effective. Although they didn't prove any statistically significant difference between groups, quality of life enhancements and stress reduction were reported. Hence, new randomized controlled trials are required in order to provide more accurate data on the potential benefits of rehabilitation strategies among post-ICU patients.

Impact of supervised aerobic exercise on clinical physiological and mental parameters of people living with HIV: a systematic review and meta-analyses of randomized controlled trials

Background: The benefits derived from supervised aerobic exercise in people living with human immunofeficiency virus- HIV (PLWH) have not yet been clearly identified.Objective: To evaluate the impact of supervised aerobic exercise on immunological, cardiorespiratory, pulmonary, hemodynamic and mental parameters of PLWH.Methods: A systematic review was carried out in accordance to PRISMA guidelines. PubMed, Physiotherapy Evidence Database (PEDro) and Cochrane Central Register of Controlled Trials (CENTRAL) were screened up to August 2021, for the identification of English written randomized trials, with participants aged 18 years and older, at any stage of the disease, with or without co-morbidities. The risk of bias assessment was conducted according to the Cochrane Collaboration's tool for assessing risk of bias. Meta- analyses were conducted using continuous, inverse variance, random-effects model.Results: Ten studies were suitable for meta-analysis based on inclusion criteria. Supervised aerobic exercise appeared to have beneficial effects on depressive symptoms [mean difference (MD)= -4.18 (confidence interval (CI)= (-6.55)-(-1.81), Z = 3.46, p = 0.0005, I²=0%, n = 2], forced expiratory volume in 1 sec [MD = 0.70, CI = 0.39-1.00, Z = 4.41, p < 0.0001, I²=0%, n = 2], and on the maximum oxygen uptake [MD = 1.38, CI = -0.02-2.78, Z = 1.94, p = 0.05, I²=94%, n = 4] of PLWH. No exercise effect was found for CD4 T-cell count (p = 0.16, n = 5), systolic blood pressure (p = 0.91, n = 2) and diastolic blood pressure (p = 0.72, n = 2).Conclusions: Supervised continuous aerobic exercise may improve lung function, depressive symptomatology and aerobic capacity of PLWH, however, the small number of available studies and the high heterogeneity concerning VO2max demonstrate the need for more research in this area.

A Cardiac Rehabilitation Program Increases the Acute Response of Endothelial Progenitor Cells to Maximal Exercise in Heart Failure Patients

PURPOSE

The purpose of this study was to investigate the effect of a cardiac rehabilitation program on the acute response on endothelial progenitor cells and circulating endothelial cells after maximal exercise in patients with chronic heart failure of different severity.

METHODS

Forty-four chronic heart failure patients were enrolled in a 36-session cardiac rehabilitation program. All patients underwent an initial maximal cardiopulmonary exercise test before and a final maximal cardiopulmonary exercise test after the cardiac rehabilitation program. The patients were divided in two groups of severity according to the median value of peak VO₂. Blood was collected at 4 time points; 2 time points at rest, and 2 time points after each cardiopulmonary exercise test. Five endothelial cellular populations were quantified by flow cytometry.

RESULTS

Although there was a higher increase in the mobilization of subgroups of endothelial progenitor cells and circulating endothelial cells after the final cardiopulmonary exercise test compared to the initial test within each severity group (p < 0.05), no significant differences between severity groups were observed (p > 0.05).

CONCLUSIONS

A 36-session cardiac rehabilitation program had similar beneficial effects on the acute response of endothelial progenitor cells and circulating endothelial cells after maximal exercise in patients with chronic heart failure of different severity.

Modalities of Exercise Training in Patients with Extracorporeal Membrane Oxygenation Support

The aim of this qualitative systematic review is to summarize and analyze the different modalities of exercise training and its potential effects in patients on extracorporeal membrane oxygenation (ECMO) support. ECMO is an outbreaking, life-saving technology of the last decades which is being used as a gold standard treatment in patients with severe cardiac, respiratory or combined cardiorespiratory failure. Critically ill patients on ECMO very often present intensive care unit-acquired weakness (ICU-AW); thus, leading to decreased exercise capacity and increased mortality rates. Early mobilization and physical therapy have been proven to be safe and feasible in critically ill patients on ECMO, either as a bridge to lung/heart transplantation or as a bridge to recovery. Rehabilitation has beneficial effects from the early stages in the ICU, resulting in the prevention of ICU-AW, and a decrease in episodes of delirium, the duration of mechanical ventilation, ICU and hospital length of stay, and mortality rates. It also improves functional ability, exercise capacity, and quality of life. Rehabilitation requires a very careful, multi-disciplinary approach from a highly specialized team from different specialties. Initial risk assessment and screening, with appropriate physical therapy planning and exercise monitoring in patients receiving ECMO therapy are crucial factors for achieving treatment goals. However, more randomized controlled trials are required in order to establish more appropriate individualized exercise training protocols.

Exercise training in heart transplantation

Heart transplantation remains the gold standard in the treatment of end-stage heart failure (HF). Heart transplantation patients present lower exercise capacity due to cardiovascular and musculoskeletal alterations leading thus to poor quality of life and reduction in the ability of daily self-service. Impaired vascular function and diastolic dysfunction cause lower cardiac output while decreased skeletal muscle oxidative fibers, enzymes and capillarity cause arteriovenous oxygen difference, leading thus to decreased peak oxygen uptake in heart transplant recipients. Exercise training improves exercise capacity, cardiac and vascular endothelial function in heart transplant recipients. Pre-rehabilitation regular aerobic or combined exercise is beneficial for patients with end-stage HF awaiting heart transplantation in order to maintain a higher fitness level and reduce complications afterwards like intensive care unit acquired weakness or cardiac cachexia. All hospitalized patients after heart transplantation should be referred to early mobilization of skeletal muscles through kinesiotherapy of the upper and lower limbs and respiratory physiotherapy in order to prevent infections of the respiratory system prior to hospital discharge. Moreover, all heart transplant recipients after hospital discharge who have not already participated in an early cardiac rehabilitation program should be referred to a rehabilitation center by their health care provider. Although high intensity interval training seems to have more benefits than moderate intensity continuous training, especially in stable transplant patients, individualized training based on the abilities and needs of each patient still remains the most appropriate approach. Cardiac rehabilitation appears to be safe in heart transplant patients. However, long-term follow-up data is incomplete and, therefore, further high quality and adequately-powered studies are needed to demonstrate the long-term benefits of exercise training in this population.

Epigenetic effects following acute and chronic exercise in cardiovascular disease: A systematic review

INTRODUCTION

Acute exercise and exercise training may confer epigenetic modifications in healthy subjects. Epigenetic effects after exercise have been showed in patients with cardiovascular disease. The aim of this systematic review was to summarize the evidence from available clinical trials that study epigenetic adaptations after exercise in patients with cardiovascular disease.

METHODS

The search strategy was performed in PubMed and CENTRAL databases on articles published until September 2020. Studies with titles and abstracts relevant to exercise epigenetic modification applied to cardiovascular patients were fully examined. Inclusion and exclusion criteria were utilized for studies screening. Quality assessment with PEDro scale and evaluation by two independent reviewers was performed.

RESULTS

Of the 1714 articles retrieved, 88 articles were assessed for eligibility criteria and 8 articles matched our search criteria and finally included in the systematic analysis. The acute exercise epigenetic (miRNAs) effects were assessed in three studies and the chronic exercise training effects (miRNAs and DNA methylation) in six studies. The results have shown that there is possibly an acute significant exercise effect on epigenetic targets which is more evident after chronic exercise training.

CONCLUSIONS

By the present systematic review, we provide preliminary evidence of beneficial epigenetic adaptations following acute and chronic exercise in patients with cardiovascular disease. More controlled studies are needed to confirm such evidence.

Effects of exercise training on diastolic and systolic dysfunction in patients with chronic heart failure

BACKGROUND

Chronic heart failure (CHF) is a complex syndrome characterized by a progressive reduction of the left ventricular (LV) contractility, low exercise tolerance, and increased mortality and morbidity. Diastolic dysfunction (DD) of the LV, is a keystone in the pathophysiology of CHF and plays a major role in the progression of most cardiac diseases. Also, it is well estimated that exercise training induces several beneficial effects on patients with CHF.

AIM

To evaluate the impact of a cardiac rehabilitation program on the DD and LV ejection fraction (EF) in patients with CHF.

METHODS

Thirty-two stable patients with CHF (age: 56 ± 10 years, EF: 32% ± 8%, 88% men) participated in an exercise rehabilitation program. They were randomly assigned to aerobic exercise (AER) or combined aerobic and strength training (COM), based on age and peak oxygen uptake, as stratified randomization criteria. Before and after the program, they underwent a symptom-limited maximal cardiopulmonary exercise testing (CPET) and serial echocardiography evaluation to evaluate peak oxygen uptake (VO_2peak), peak workload (W_peak), DD grade, right ventricular systolic pressure (RVSP), and EF.

RESULTS

The whole cohort improved VO_2peak, and W_peak, as well as DD grade (P < 0.05). Overall, 9 patients (28.1%) improved DD grade, while 23 (71.9%) remained at the same DD grade; this was a significant difference, considering DD grade at baseline (P < 0.05). In addition, the whole cohort improved RVSP and EF (P < 0.05). Not any between-group differences were observed in the variables assessed (P > 0.05).

CONCLUSION

Exercise rehabilitation improves indices of diastolic and systolic dysfunction. Exercise protocol was not observed to affect outcomes. These results need to be further investigated in larger samples.

Effects on the left ventricular diastolic dysfunction of a cardiac rehabilitation program in chronic heart failure patients

Funding Acknowledgements

Type of funding sources: None.

PURPOSE

The aim of the present study is to evaluate the impact of a cardiac rehabilitation program on the diastolic dysfunction, the ejection fraction (EF) of left ventricular and the volume index of the left atrium comparing 2 groups: those with restricted EF (&lt;40%) and those with intermediate and preserved EF (≥ 40%).

METHODS

In the present study 41 stable CHF patients (N = 41; 56 ±10 years [mean ± SD], 34 males and 7 females) with diastolic dysfunction, participated in an exercise rehabilitation program (3 sessions a week). Only 38 of them completed the rehabilitation program in the form of circuit-interval aerobic training, adjusted according to 70–80% of heart rate reserve, for a period of 3 months. A detailed echocardiogram was performed before and immediately after the rehabilitation program, focusing on the diastolic dysfunction assessment of the left ventricular.

RESULTS

At the end of the three months rehabilitation program, the diastolic dysfunction stage was significantly decreased (from 1.45+/- 0.72 to 1.08 +/-0.67, p = .000). The LV ejection fraction was significantly increased (from 34.97+/-10.66 to 36.68 +/-10.52, p = .002). In addition, there was a significant decrease in E/E" and RVSP (from 9.37+/-3.54 to 8.47+/-3.34 and from 28.44+/-6.86mmHg to 27.38+/-5.87 mmHg, p =.033 and p =.030, respectively). Finally, the left atrial volume and the average e" had no significant decrease.

CONCLUSIONS

Circuit training improved both diastolic and systolic dysfunction but had no significant repercussion on the left atrium volume. From this study it was concluded that a rehabilitation cardiac program can have an impact in the improvement in the diastolic dysfunction, especially in the restricted EF group, a mechanism that is essential in the pathophysiology of the CHF.

Table 1 PairedDifferences t df Sig. (2-tailed) Mean Std. Deviation Std. ErrorMean 95% Confidence Interval of the Difference Lower Upper Diast.stage b-a 0.368 .589 .096 .175 .562 3.855 37 .000 A b - A a ( m/sec) -.03816 .21084 .03420 -.10746 .03114 -1.116 37 .272 Ε/Α b - Ε/Α a .11039 .44705 .07252 -.03655 .25734 1.522 37 .136 mean e" b - a(cm/sec) .19395 2.56304 .41578 -.64850 1.03640 .466 37 .644 Ε/e "b - Ε/e "a .90026 2.50613 .40655 .07652 1.72401 2.214 37 .033 DTeb -DTe a (msec) 8.500 44.324 7.190 -6.069 23.069 1.182 37 .245 T-Test for the measured diastolic parameters (diastolic stage, E, A, E/A, mean e", E/E", DTe) for all groups (b = before, a = after).

Abstract Figure. Linear scatter plot for EF

Survivin and caspases serum protein levels and survivin variants mRNA expression in sepsis

Sepsis is a dysregulated host response to infection related to devastating outcomes. Recently, interest has been shifted towards apoptotic and antiapoptotic pathobiology. Apoptosis is executed through the activation of caspases regulated by a number of antiapoptotic proteins, such as survivin. The survivin and caspases’ responses to sepsis have not yet been elucidated. This is a multicenter prospective observational study concerning patients with sepsis (n = 107) compared to patients with traumatic systemic inflammatory response syndrome (SIRS) (n = 75) and to healthy controls (n = 89). The expression of survivin was quantified through real-time quantitative polymerase chain reaction for the different survivin splice variants (wild type-WT, ΔEx3, 2B, 3B) in peripheral blood leukocytes. The apoptotic or antiapoptotic tendency was specified by measuring survivin-WT, caspase-3, and -9 serum protein concentrations through enzyme-linked immunosorbent assay. The survivin-WT, -2B, -ΔΕx3 mRNA, survivin protein, and caspases showed an escalated increase in SIRS and sepsis, whereas survivin-3B was repressed in sepsis (p < 0.05). Survivin correlated with IL-8 and caspase-9 (p < 0.01). For discriminating sepsis, caspase-9 achieved the best receiver operating characteristic curve (AUROC) of 0.95. In predicting mortality, caspase-9 and survivin protein achieved an AUROC of 0.70. In conclusion, specific apoptotic and antiapoptotic pathways might represent attractive targets for future research in sepsis.

Neutrophil Gelatinase-Associated Lipocalin Measured on Clinical Laboratory Platforms for the Prediction of Acute Kidney Injury and the Associated Need for Dialysis Therapy: A Systematic Review and Meta-analysis

RATIONALE & OBJECTIVE

The usefulness of measures of neutrophil gelatinase-associated lipocalin (NGAL) in urine or plasma obtained on clinical laboratory platforms for predicting acute kidney injury (AKI) and AKI requiring dialysis (AKI-D) has not been fully evaluated. We sought to quantitatively summarize published data to evaluate the value of urinary and plasma NGAL for kidney risk prediction.

STUDY DESIGN

Literature-based meta-analysis and individual-study-data meta-analysis of diagnostic studies following PRISMA-IPD guidelines.

SETTING & STUDY POPULATIONS

Studies of adults investigating AKI, severe AKI, and AKI-D in the setting of cardiac surgery, intensive care, or emergency department care using either urinary or plasma NGAL measured on clinical laboratory platforms.

SELECTION CRITERIA FOR STUDIES

PubMed, Web of Science, Cochrane Library, Scopus, and congress abstracts ever published through February 2020 reporting diagnostic test studies of NGAL measured on clinical laboratory platforms to predict AKI.

DATA EXTRACTION

Individual-study-data meta-analysis was accomplished by giving authors data specifications tailored to their studies and requesting standardized patient-level data analysis.

ANALYTICAL APPROACH

Individual-study-data meta-analysis used a bivariate time-to-event model for interval-censored data from which discriminative ability (AUC) was characterized. NGAL cutoff concentrations at 95% sensitivity, 95% specificity, and optimal sensitivity and specificity were also estimated. Models incorporated as confounders the clinical setting and use versus nonuse of urine output as a criterion for AKI. A literature-based meta-analysis was also performed for all published studies including those for which the authors were unable to provide individual-study data analyses.

RESULTS

We included 52 observational studies involving 13,040 patients. We analyzed 30 data sets for the individual-study-data meta-analysis. For AKI, severe AKI, and AKI-D, numbers of events were 837, 304, and 103 for analyses of urinary NGAL, respectively; these values were 705, 271, and 178 for analyses of plasma NGAL. Discriminative performance was similar in both meta-analyses. Individual-study-data meta-analysis AUCs for urinary NGAL were 0.75 (95% CI, 0.73-0.76) and 0.80 (95% CI, 0.79-0.81) for severe AKI and AKI-D, respectively; for plasma NGAL, the corresponding AUCs were 0.80 (95% CI, 0.79-0.81) and 0.86 (95% CI, 0.84-0.86). Cutoff concentrations at 95% specificity for urinary NGAL were>580ng/mL with 27% sensitivity for severe AKI and>589ng/mL with 24% sensitivity for AKI-D. Corresponding cutoffs for plasma NGAL were>364ng/mL with 44% sensitivity and>546ng/mL with 26% sensitivity, respectively.

LIMITATIONS

Practice variability in initiation of dialysis. Imperfect harmonization of data across studies.

CONCLUSIONS

Urinary and plasma NGAL concentrations may identify patients at high risk for AKI in clinical research and practice. The cutoff concentrations reported in this study require prospective evaluation.

Endothelial progenitor cells mobilization after maximal exercise according to heart failure severity

BACKGROUND

Vascular endothelial dysfunction is an underlying pathophysiological feature of chronic heart failure (CHF). Patients with CHF are characterized by impaired vasodilation and inflammation of the vascular endothelium. They also have low levels of endothelial progenitor cells (EPCs). EPCs are bone marrow derived cells involved in endothelium regeneration, homeostasis, and neovascularization. Exercise has been shown to improve vasodilation and stimulate the mobilization of EPCs in healthy people and patients with cardiovascular comorbidities. However, the effects of exercise on EPCs in different stages of CHF remain under investigation.

AIM

To evaluate the effect of a symptom-limited maximal cardiopulmonary exercise testing (CPET) on EPCs in CHF patients of different severity.

METHODS

Forty-nine consecutive patients (41 males) with stable CHF [mean age (years): 56 ± 10, ejection fraction (EF, %): 32 ± 8, peak oxygen uptake (VO₂, mL/kg/min): 18.1 ± 4.4] underwent a CPET on a cycle ergometer. Venous blood was sampled before and after CPET. Five circulating endothelial populations were quantified by flow cytometry: Three subgroups of EPCs [CD34⁺/CD45^-/CD133⁺, CD34⁺/CD45^-/CD133⁺/VEGFR₂ and CD34⁺/CD133⁺/vascular endothelial growth factor receptor 2 (VEGFR₂)] and two subgroups of circulating endothelial cells (CD34⁺/CD45^-/CD133^- and CD34⁺/CD45^-/CD133^-/VEGFR₂). Patients were divided in two groups of severity according to the median value of peak VO₂ (18.0 mL/kg/min), predicted peak VO₂ (65.5%), ventilation/carbon dioxide output slope (32.5) and EF (reduced and mid-ranged EF). EPCs values are expressed as median (25th-75th percentiles) in cells/10⁶ enucleated cells.

RESULTS

Patients with lower peak VO₂ increased the mobilization of CD34⁺/CD45^-/CD133⁺ [pre CPET: 60 (25-76) vs post CPET: 90 (70-103) cells/10⁶ enucleated cells, P < 0.001], CD34⁺/CD45^-/CD133⁺/VEGFR₂ [pre CPET: 1 (1-4) vs post CPET: 5 (3-8) cells/10⁶ enucleated cells, P < 0.001], CD34⁺/CD45^-/CD133^- [pre CPET: 186 (141-361) vs post CPET: 488 (247-658) cells/10⁶ enucleated cells, P < 0.001] and CD34⁺/CD45^-/CD133^-/VEGFR₂ [pre CPET: 2 (1-2) vs post CPET: 3 (2-5) cells/10⁶ enucleated cells, P < 0.001], while patients with higher VO₂ increased the mobilization of CD34⁺/CD45^-/CD133⁺ [pre CPET: 42 (19-73) vs post CPET: 90 (39-118) cells/10⁶ enucleated cells, P < 0.001], CD34⁺/CD45^-/CD133⁺/VEGFR₂ [pre CPET: 2 (1-3) vs post CPET: 6 (3-9) cells/10⁶ enucleated cells, P < 0.001], CD34⁺/CD133⁺/VEGFR₂ [pre CPET: 10 (7-18) vs post CPET: 14 (10-19) cells/10⁶ enucleated cells, P < 0.01], CD34⁺/CD45^-/CD133^- [pre CPET: 218 (158-247) vs post CPET: 311 (254-569) cells/10⁶ enucleated cells, P < 0.001] and CD34⁺/CD45^-/CD133^-/VEGFR₂ [pre CPET: 1 (1-2) vs post CPET: 4 (2-6) cells/10⁶ enucleated cells, P < 0.001]. A similar increase in the mobilization of at least four out of five cellular populations was observed after maximal exercise within each severity group regarding predicted peak, ventilation/carbon dioxide output slope and EF as well (P < 0.05). However, there were no statistically significant differences in the mobilization of endothelial cellular populations between severity groups in each comparison (P > 0.05).

CONCLUSION

Our study has shown an increased EPCs and circulating endothelial cells mobilization after maximal exercise in CHF patients, but this increase was not associated with syndrome severity. Further investigation, however, is needed.

A cardiac rehabilitation program increases the acute respond of endothelial progenitor cells after maximum exercise in patients with chronic heart failure

Background

Chronic heart failure (CHF) remains a leading cause of morbidity and mortality and it is characterized by vascular endothelial dysfunction. During the last decades, endothelial progenitor cells (EPCs) are being used as an index of the endothelium restoration potential, therefore reflecting the vascular endothelial function. Exercise training has been shown to stimulate the mobilization of EPCs at rest in CHF patients. However, the effect of exercise training on the acute respond of EPCs after maximum exercise in CHF patients remains unknown.

Purpose

The purpose of the study was to assess the effect of a cardiac rehabilitation (CR) program on the acute respond of EPCs after maximum exercise in patients with CHF.

Methods

Forty-four consecutive patients (35 males) with stable CHF [mean±SD, Age (years): 56±10, BMI (kg/m2): 28.7±5.2, EF (%): 33±8, Peak VO2 (ml/kg/min): 18.4±4.4, Peak work rate (watts): 101±39] enrolled a 36-session CR program based on high-intensity interval exercise training. All patients underwent an initial symptom limited maximal cardiopulmonary exercise testing (CPET) on an ergometer before the CR program and a final maximal CPET after the CR program. Venous blood was drawn before and after each CPET. Five circulating endothelial populations were identified and quantified by flow cytometry; CD34+/CD45-/CD133+, CD34+/CD45-/CD133+/VEGFR2, CD34+/CD133+/VEGFR2, CD34+/CD45-/CD133- and CD34+/CD45-/CD133-/VEGFR2. EPCs values are expressed as cells/million enucleated cells in medians (25th-75th percentiles).

Results

The acute mobilization of EPCs after the final CPET was higher than after the initial CPET in 4 out of 5 circulating endothelial populations. Most specifically, difference of the acute mobilization of CD34+/CD45-/CD133+ cells [initial CPET: 25 (15–46) vs final CPET: 49 (26–71), p=0.002], CD34+/CD45-/CD133+/VEGFR2 cells [initial CPET: 3 (2–5) vs final CPET: 8 (5–12), p&lt;0.001], CD34+/CD45-/CD133- cells [initial CPET: 129 (52–338) vs final CPET: 250 (129–518), p=0.03] and CD34+/CD45-/CD133-/VEGFR2 cells [initial CPET: 2 (1–4) vs final CPET: 6 (3–9), p&lt;0.001] increased after the final CPET. The acute mobilization of CD34+/CD133+/VEGFR2 cells [initial CPET: 3 (−1–7) vs final CPET: 5 (0–15), p=0.441] did not differ between the 2 CPETS.

Conclusion

A 36-session cardiac rehabilitation program increases the acute respond of endothelial progenitor cells after maximum cardiopulmonary exercise training in patients with chronic heart failure, therefore indicating the beneficial effect of exercise training on the vascular endothelial function.

Funding Acknowledgement

Type of funding source: Public grant(s) – EU funding. Main funding source(s): Co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning” in the context of the project