Table 2. Characteristics and outcomes of the included studies.

STEMI = ST-Elevation Myocardial Infarction, CAG = Coronary Angiography, PCI = Percutaneous Coronary Intervention, PPCI = Primary Percutaneous Coronary Intervention, LVEF = Left Ventricular Ejection Fraction, CABG = Coronary artery bypass grafting, CK = Creatine Kinase, H/o = History of, MI = Myocardial Infarction, CCT = Controlled Clinical Trial, CT = Clinical Trial, MNC = Mononuclear stem cells, CCTA = Coronary Computed Tomography Angiography, RCT = Randomized Controlled Trial, BMMNC = Bone Marrow Mononuclear Cell, BNP = B-type natriuretic peptide, WMSI = Wall Motion Score Index, N-BMC = Normoxia Bone Marrow Mononuclear Cells, HP-BMC = Hypoxia Preconditioned Bone Marrow Mononuclear Cells, ECG = Electrocardiogram, SPECT = Single-Photon Emission Computed Tomography, LV = Left Ventricle, MRI = Magnetic Resonance Imaging, CT scan = Computed Tomography scan, F-18-FDG-PET = F-18-Fluorodeoxyglucose Positron Emission Computed Tomography, 99mTc-SPECT= 99mTc-sestamibi Single-Photon Emission Computed Tomography, G-CSF = Granulocyte Colony-Stimulating Factor, MSCs = Mesenchymal Stem Cells, WJ-MSC = Wharton’s jelly-derived Mesenchymal Stem Cells, CDC = Cardio sphere-derived autologous stem cell, LVEDD = End-Diastolic Dimension of the Left Ventricle, LVESV = End-Systolic Volume of the Left Ventricle, LVEDV = End-Diastolic Volume of the Left Ventricle, SPCs = Stem/ Progenitor Cells, LIN- = Lineage-negative, CADUCEUS = CArdiosphere-Derived aUtologous stem CElls to reverse ventricUlar dySfunction, TIME trial = Timing in Myocardial Infarction Evaluation trial

Author	Country/Year	Study design	Patient characteristics	Sample size	Treatment group	Control group	Follow-up period	Outcome
Benedek et al. [8]	Romania / 2014	CCT	Adult with h/o STEMI and PPCI and abnormalities in wall motion and less than 50% stenosis	18	Autologous MNC = 9	Placebo = 9	Four years with clinical examinations, ECG, Echocardiography, 64-slice CCTA	A small improvement in EF and the plaque burden is lower in coronary segments treated with stem cells
Alestalo et al. [9]	Finland / 2015	Double-blinded RCT	H/o STEMI, < 75 years, hemodynamically stable and no cardiogenic shock or rescue PCI/CABG	26	BMMNC = 14	Placebo = 12	Cytokines after four days and LV angiogram after six months	A balancing effect between the anti-inflammatory and proinflammatory cytokine BMMNC group at day four
Bozdag-Turan et al. [10]	Germany / 2012	CCT	18–80 years with h/o STEMI, absence of co-morbidities, cancer, and active bleeding or trauma in the last two months	24	BMC = 12	Placebo = 12	Six months with left ventriculography	Infarct size and BNP level decreased, and global EF and infarct wall movement velocity were increased in the stem cell group
Choudry et al.  [11]	5 centers in Europe [United Kingdom (3); Switzerland (1); Denmark (1)] / 2016	Double-blinded RCT	Acute anterior MI with anterior wall motion abnormality and h/o PPCI	100	BMMNC = 55	Placebo = 45	One year with cardiac MRI and Echocardiography	Small non-significant improvement in LVEF
Duan et al. [12]	China / 2015	RCT	H/o MI, < 75 years with planned CABG for triple-vessel disease, LVEF < 30%, and no aneurysm or valvular diseases	42	CABG + BMMNC = 24	Only CABG  = 18	One year with Echocardiography	Improvement in left ventricular functions in the treatment group
Gao et al. [6]	China / 2015	Double-blinded RCT	18-80 years with a h/o STEMI and reperfusion with stent implantation and LV local wall-motion abnormality. CK > three-fold the upper limit of the normal	116	WJ-MSC = 58	Placebo = 58	18 months with F-18-FDG-PET and 99mTc-SPECT and two-dimensional Echocardiography	LVEF significantly increased and LVESV and LVEDV greatly decreased in the treatment group
Hu et al. [13]	China / 2015	RCT	18-75 years old with acute STEMI and PPCI with stent implantation or thrombolysis and LV local wall motion abnormality	36	N-BMCs = 11, HP-BMCs = 11	Standard therapy = 14	Six and 12 months	Improvement in changes of LVEDV, LVESV, and WMSI in the HP-BMC group. Myocardial perfusion defect ratio was reduced in HP-BMCs and N-BMC groups at six months
Huan et al. [14]	China / 2015	CT	18-75 years old with a h/o acute STEMI and treatment with PCI, LVEF < 50%	104	Group A = BMMNC within two hours after PCI = 27, Group B = three-seven days after PCI = 26, Group C = seven to 30 days after PCI = 26	Placebo = 25 patients	Six months with angiography. SPECT and Echocardiography at six and 12 months	Effects of cell therapy given within 24 hours are the same as to given three-seven days after PPCI
Kim et al. [15]	South Korea / 2018	RCT	STEMI	26	BMMNC = 14	Placebo = 12	Four and 12-months with SPECT	Increase in the LVEF from baseline to the fourth month and twelfth month in the bone marrow mesenchymal stem cells group.
Lee et al.  [16]	Korea / 2014	CT	18-70 years old with STEMI	69	MSC = 33	Placebo = 36	Six months with SPECT	Safe with modest improvement in LVEF
Makkar et al. [17]	USA / 2012	CT	H/o two to four weeks of MI and LVEF = 25–45%	25	Cardio sphere-derived autologous stem cells = 17	Standard therapy = 8	Six months with MRI	Scar mass was reduced, increase in viable heart mass and regional contractility in the CDC group.   LVEDV, LVESV, and LVEF were the same in the two groups
Malliaras et al.  [18]	USA / 2014	RCT	Patients of CADUCEUS trial were followed up for a year	25	Cardio sphere-derived autologous stem cells = 17	Standard therapy = 8	One year with MRI	Scar size reduced, increased viable myocardium, and improved regional function of infarcted myocardium
Micheu et al. [19]	Romania / 2015	CT	18-81 years old with STEMI & h/o angioplasty with stent implantation, LVEF < 40%.	18	Autologous BMCs = 7	Standard therapy = 11	Six months with clinical examination, Echocardiography, 24 hours ECG	Safe and LVEF was increased
Moccetti et al. [20]	Switzerland / 2012	CT	Acute anterior STEMI treated by PPCI and LVEF < 50%.	60	Autologous BMMNC = 23	Standard therapy = 37	Five years with Echocardiography	Safe and LV function improved
Moreira et al.  [21]	Brazil / 2011	RCT	18-80 years old with h/o MI and reperfusion and involving more than 10% of the LV	30	BMMNC via anterograde intra-arterial coronary (IAC) delivery = 14, BMMNC via retrograde intravenous coronary (IVC) delivery = 10	Placebo = 6	Cardiac MRI was performed before cell injection	The retrograde approach to deliver stem cells was safe and cell retention by cardiac tissue is more in the anterograde approach
Nair et al.  [22]	India / 2015	RCT	Anterior MI and LVEF = 20-50%, 20-65 years with h/o CAG between one to three weeks	250	Stem cell therapy + standard care = 125	Standard care = 125	Six months with Echocardiography	Safe, but not clinically significant
Naseri et al.  [23]	Iran / 2018	RCT	18-75 years old with a h/o acute MI infarction, eligible for elective CABG	77	CD133 (+) = 21, MNC = 30	Placebo = 26	Six and 18 months after CABG with SPECT	Significant differences were seen between the MNC and placebo groups in LVEF and a decrease in the LV thickening
Nicolau et al.  [24]	Brazil / 2018	RCT	30-80 years, LVEF ≤ 50%, and regional dysfunction in the infarct-related area	120	BMMNC = 66	Placebo = 55	Six months with MRI	No significant effects
Peregud-Pogorzelska et al. [25]	Poland / 2020	CCT not randomized	<65 years old with first MI and EF ≤ 45%	34	Standard therapy + autologous BM-derived LIN- SPCs = 15	Only standard therapy = 19	One, three, six months, and one year with Echocardiography	Safe and > 10% improvement in LVEF is noticed at 12 months
Quyyumi et al.  [26]	USA / 2017	RCT	STEMI with a stent and LVEF ≤ 48% and ≥ four days post stent	161	Intracoronary infusion of autologous CD34 (+) cell  = 78	Placebo = 83	Six months with SPECT	Safe
Rodrigo et al. [27]	Netherlands / 2013	CCT	First acute STEMI treated with PPCI and maximum CK level was > 1,600 U/L	54	MSC = 9	Standard therapy = 45 matched but nonrandomized patients	Three, six months, one year, four-five years with Echocardiography, Holter, and clinical examination	Improvements in LV function but not significantly different when compared to controls
Roncalli et al. [28]	France / 2011	RCT	Acute MI and successful reperfusion with LVEF ≤ 45%, age 18–75 years	101	BMMNC = 52	Placebo = 49	Three months with MRI, Echocardiography, and SPECT	Multivariate analysis shows improvement of myocardial viability than univariate analysis
San Roman et al.  [29]	Spain / 2015	RCT	Adult, acute MI with PPCI or post-fibrinolysis PCI and rapamycin drug-eluting stent implantation	120	BMMNC = 30, GCSF = 30, G-CSF + cells = 29	Standard therapy = 31	12 months with cardiac MRI	Not many differences among the four groups
Shah et al. [3]	India / 2014	CT	30-70 years old, acute MI with PCI	19	Autologous BMCS = 12	Standard therapy = 7	24 months with Echocardiography, ECG, Holter monitoring	Increase in LVEF with LV function improvements in stem cell group
Srimahachota et al. [30]	Thailand / 2011	RCT	H/o STEMI with LVEF < 50% and PCI	23	Autologous BMCs = 11	Standard therapy = 12	Six months with cardiac MRI	Symptoms improved than baseline, but not many significant changes were noticed in the two groups
Sürder et al. [31]	Switzerland / 2013	RCT	Acute MI	200	BMMNC five-seven days after STEMI = 66, BMMNC three to four weeks after STEMI = 67	Standard therapy = 67	Four months with cardiac MRI	No significant improvements
Traverse et al. [32]	USA / 2012	RCT	MI and PCI, LVEF < 45%	120	BMMNC at day three or day seven randomly = 79	Placebo = 41	Six months with cardiac MRI	No significant improvement
Traverse et al. [33]	USA / 2011	RCT	Acute MI and PCI, LVEF < 45%	87	BMMNC after two to three weeks of MI = 58	Placebo = 29	Six months with cardiac MRI	No significant improvement
Traverse et al. [34]	USA / 2018	RCT	Patients of TIME trial, acute MI and PCI, LVEF < 45%	120	BMMNC at day three or day seven randomly = 79. 58 patients were followed up	Placebo = 41, 27 patients were followed up	Two years with cardiac MRI	No significant improvement
Turan et al. [35]	Germany / 2011	RCT	18-80 years old with MI and LV dysfunction	56	BMMNC = 38	Placebo = 18	Three, six months, and one year with left ventriculography	Decrease in infarct size but an increase of global EF and infarct wall movement velocity in stem cell group
Yerebakan et al. [36]	Germany / 2011	RCT	MI at least 14 days before admission and LV akinesia with an indication for CABG	55	Intramyocardial CD133 (+) BMCs + CABG = 35	Only CABG = 20	18 months with 24-hour Holter monitoring, echocardiography, MRI, and CT scan	Intramyocardial stem cell therapy was tolerable but did not have significant improvements