A Systematic Review and Meta-Analysis: Safety and Efficacy of Mesenchymal Stem Cells Therapy for Heart Failure.

Preclinical and clinical evidence suggests that mesenchymal stem cells (MSCs) may be beneficial in treating Heart Failure (HF). However, the effects of stem cell therapy in patients with heart failure is an ongoing debate and the safety and efficacy of MSCs therapy are not well-known. We conducted a systematic review of clinical trials that evaluated the safety and efficacy of MSCs for HF. This study aimed to assess the safety and efficacy of MSCs therapy compared to the placebo in heart failure patients. We searched PubMed, Embase, Cochrane library systematically, with no language restrictions. Randomized Controlled Trials (RCTs) assessing the influence of MSCs treatment function controlled with placebo in heart failure were included in this analysis. We included RCTs with data on safety and efficacy in patients with heart failure after mesenchymal stem cell transplantation. Two investigators independently searched the articles, extracted data, and assessed the quality of the included studies. Pooled data was performed using the fixed-effect model or random-effect model by the use of Review Manager 5.3. The Cochrane risk of bias tool was used to assess the bias of included studies. The primary outcome was safely assessed by death and rehospitalization and the secondary outcome was efficacy, which was assessed by six-minute walk distance and Left Ventricular Ejection Fraction (LVEF), Left Ventricular End-systolic Volume (LVESV), Left Ventricular End-diastolic Volume (LVEDV) and Brain Natriuretic Peptide (BNP). A total of twelve studies were included, involving 823 patients who underwent MSCs or placebo treatment. The overall rate of death showed a trend of reduction of 27% (RR [CI]=0.73 [0.49, 1.09], p=0.12) in the MSCs treatment group. The incidence of rehospitalization was reduced by 47% (RR [CI]=0.53[0.38, 0.75], p=0.0004). The patients in the MSCs treatment group realised an average of 117.01m (MD [95% CI]=117.01m [94.87, 139.14], p<0.00001) improvement in 6MWT. MSCs transplantation significantly improved Left Ventricular Ejection Fraction (LVEF) by 5.66 % (MD [95% CI]=5.66 [4.39, 6.92], p<0.00001), decreased Left Ventricular End-Systolic Volume (LVESV) by 14.75 ml (MD [95% CI]=-14.75 [-16.18, - 12.83], p<0.00001) and Left Ventricular End-Diastolic Volume (LVEDV) by 5.78 ml (MD [95% CI]=- 5.78[-12.00, 0.43], p=0.07), in the MSCs group, BNP was decreased by 133.51 pg/ml MD [95% CI]= - 133.51 [-228.17,-38.85], p=0.54, I2= 0.0%) than did in the placebo group. Our results suggested that mesenchymal stem cells as a regenerative therapeutic approach for heart failure are safe and effective by virtue of their self-renewal potential, vast differentiation capacity and immune modulating properties. Allogenic MSCs have superior therapeutic effects and intracoronary injection is the optimum delivery approach. In the tissue origin, patients who received treatment with umbilical cord MSCs seem more effective than bone marrow MSCs. As to dosage injected, (1-10)*10^8 cells were of better effect.

Shen T ，Xia L ，Dong W ，Wang J ，Su F ，Niu S ，Wang Q ，Fang Y ... -  《-》

Efficacy of mesenchymal stem cell transplantation on major adverse cardiovascular events and cardiac function indices in patients with chronic heart failure: a meta-analysis of randomized controlled trials.

The effects of mesenchymal stem cells (MSCs) on heart failure (HF) have been controversial. This study was conducted to investigate whether the transplantation of MSCs after HF could help improve clinical outcomes and myocardial performance indices. Using a systematic approach, electronic databases were searched for randomized controlled trials (RCTs), which evaluated the transplantation of MSCs after HF. The outcomes owf interest included clinical outcomes and myocardial function indices. We also assessed the role of age, cause of heart failure, cell origin, cell number, type of donor (autologous/allogeneic), and route of cell delivery on these outcomes. Using the random-effects method, a relative risk (RR) or mean difference (MD) and their corresponding 95% confidence intervals (CI) were pooled. Seventeen RCTs including 1684 patients (927 and 757 patients in the intervention and control arms, respectively) were enrolled. The RR (95% CI) of mortality was 0.78 (0.62; 0.99, p = 0.04) in the MSC group compared to the controls. HF rehospitalization decreased in the MSC group (RR = 0.85 (0.71-1.01), p = 0.06), but this was only significant in those who received autologous MSCs (RR = 0.67 (0.49; 0.90), p = 0.008). LVEF was significantly increased among those who received MSC (MD = 3.38 (1.89; 4.87), p < 0.001). LVESV (MD = -9.14 (-13.25; -5.03), p < 0.001), LVEDV (MD = -8.34 -13.41; -3.27), p < 0.001), and scar size (standardized MD = -0.32 (-0.60; -0.05), p = 0.02) were significantly decreased. NYHA class (MD = -0.19 (-0.34; -0.06), p = 0.006), BNP level (standardized MD = -0.28 (-0.50; -0.06), p = 0.01), and MLHFQ (MD = -11.55 (-16.77; -6.33), p = 0.005) significantly decreased and 6-min walk test significantly improved (MD = 36.86 (11.22; 62.50), p = 0.001) in the MSC group. Trials were not affected by the participants' etiology of heart failure, while trials with the autologous source of cells, MSC doses lower than 100 million cells, and intracoronary injection performed significantly better in some of the outcomes. Transplantation of MSCs for ischemic or dilated heart failure patients may reduce all-cause mortality and improve clinical condition. Moreover, this treatment would improve left ventricular function indices and reduce scar size.

Kavousi S ，Hosseinpour A ，Bahmanzadegan Jahromi F ，Attar A ... -  《Journal of Translational Medicine》

Efficacy and Safety of Mesenchymal Stem Cell Therapy in Patients with Acute Myocardial Infarction: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

The adjuvant treatment of stem cell therapy for acute myocardial infarction (AMI) has been studied in multiple clinical trials, but many questions remain to be addressed, such as efficacy, safety, identification of the optimal cell type, tractable route of delivery, transplant dosage, and transplant timing. The current meta-analysis aimed to explore the issues of mesenchymal stem cells (MSCs) transplantation in patients with AMI based on published randomized controlled trials (RCTs) and guide the design of subsequent clinical trials of MSCs therapy for AMI. The Cochrane Library, PubMed, EMBASE databases were searched for relevant clinical trials from January 1, 2000, to January 23, 2021. Results from RCTs involving MSCs transplantation for the treatment of AMI were identified. According to the Cochrane systematic review method, the literature quality, including studies, was evaluated and valid data was extracted. Rev- Man 5.3 and Stata 15.1 software were used for Meta-analysis. After literature search and detailed evaluation, 9 randomized controlled trials enrolling 460 patients were included in the quantitative analysis. Pooled analyses indicated that MSCs therapy was associated with a significantly greater improvement in overall left ventricular ejection fraction (LVEF), and the effect was maintained for up to 24 months. No significant difference in favor of MSCs treatment in left ventricular (LV) volume and in the risk of rehospitalization as a result of heart failure (HF) was noted, compared with the controls. For transplantation dose, the LVEF of patients accepting a MSCs dose of 107-108 cells was significantly increased by 2.62% (95% CI 1.54 to 3.70; P < 0.00001; I2 =0%), but this increase was insignificant in the subgroup that accepted a MSCs dose of < 107 cells (1.65% in LVEF, 95% CI, 0.03 to 3.27; P =0.05; I2 =75%) or >108 cells (4.65% in LVEF, 95% CI, -4.55 to 13.48; P =0.32; I2 =95%), compared with the controls. For transplantation timing, a significant improvement of LVEF of 3.18% was achieved in the group of patients accepting a MSCs infusion within 2 to 14 days after percutaneous coronary intervention (PCI) (95% CI, 2.89 to 3.47; P <0.00001; I2 = 0). There was no association between MSCs therapy and major adverse events. Results from our systematic review suggest that MSCs therapy for patients with AMI appears to be safe and might induce a significant increase in LVEF with a limited impact on LV volume and rehospitalization caused by HF. The effect was maintained for up to 24 months. MSCs dose of 107-108 cells was more likely to achieve better clinical endpoints than <107 or >108 cells. The optimal time window for cell transplantation might be within 2-14 days after PCI. This meta-analysis was registered with PROSPERO, number CRD 42021241104.

Yu J ，Zhang RF ，Mao YL ，Zhang H ... -  《-》

Comparative effectiveness of mesenchymal stem cell versus bone-marrow mononuclear cell transplantation in heart failure: a meta-analysis of randomized controlled trials.

There is no clear evidence on the comparative effectiveness of bone-marrow mononuclear cell (BMMNC) vs. mesenchymal stromal cell (MSC) stem cell therapy in patients with chronic heart failure (HF). Using a systematic approach, eligible randomized controlled trials (RCTs) of stem cell therapy (BMMNCs or MSCs) in patients with HF were retrieved to perform a meta-analysis on clinical outcomes (major adverse cardiovascular events (MACE), hospitalization for HF, and mortality) and echocardiographic indices (including left ventricular ejection fraction (LVEF)) were performed using the random-effects model. A risk ratio (RR) or mean difference (MD) with corresponding 95% confidence interval (CI) were pooled based on the type of the outcome and subgroup analysis was performed to evaluate the potential differences between the types of cells. The analysis included a total of 36 RCTs (1549 HF patients receiving stem cells and 1252 patients in the control group). Transplantation of both types of cells in patients with HF resulted in a significant improvement in LVEF (BMMNCs: MD (95% CI) = 3.05 (1.11; 4.99) and MSCs: MD (95% CI) = 2.82 (1.19; 4.45), between-subgroup p = 0.86). Stem cell therapy did not lead to a significant change in the risk of MACE (MD (95% CI) = 0.83 (0.67; 1.06), BMMNCs: RR (95% CI) = 0.59 (0.31; 1.13) and MSCs: RR (95% CI) = 0.91 (0.70; 1.19), between-subgroup p = 0.12). There was a marginally decreased risk of all-cause death (MD (95% CI) = 0.82 (0.68; 0.99)) and rehospitalization (MD (95% CI) = 0.77 (0.61; 0.98)) with no difference among the cell types (p > 0.05). Both types of stem cells are effective in improving LVEF in patients with heart failure without any noticeable difference between the cells. Transplantation of the stem cells could not decrease the risk of major adverse cardiovascular events compared with controls. Future trials should primarily focus on the impact of stem cell transplantation on clinical outcomes of HF patients to verify or refute the findings of this study.

Hosseinpour A ，Kamalpour J ，Dehdari Ebrahimi N ，Mirhosseini SA ，Sadeghi A ，Kavousi S ，Attar A ... -  《Stem Cell Research & Therapy》

Stem cell therapy for chronic ischaemic heart disease and congestive heart failure.

Fisher SA ，Brunskill SJ ，Doree C ，Mathur A ，Taggart DP ，Martin-Rendon E ... -  《Cochrane Database of Systematic Reviews》