Evaluation of metoprolol standard dosing pathway in Chinese patients with acute coronary syndrome: a prospective multicenter single-arm interventional study / 老年心脏病学杂志（英文版）

OBJECTIVE@#To evaluate the feasibility and tolerability of metoprolol standard dosing pathway (MSDP) in Chinese patients with acute coronary syndrome (ACS).@*METHODS@#In this multicenter, prospective, open label, single-arm and interventional study that was conducted from February 2018 to April 2019 in fifteen Chinese hospitals. A total of 998 hospitalized patients aged ≥ 18 years and diagnosed with ACS were included. The MSDP was applied to all eligible ACS patients based on the standard treatment recommended by international guidelines. The primary endpoint was the percentage of patients achieving the target dose at discharge (V2). The secondary endpoints included the heart rate and blood pressure at V2 and four weeks after discharge (V4), and percentage of patients experiencing bradycardia (heart rate < 50 beats/min), hypotension (blood pressure < 90/60 mmHg) and transient cardiac dysfunction at V2 and V4.@*RESULTS@#Of the 998 patients, 29.46% of patients achieved the target dose (≥ 95 mg/d) at V2. The total population was divided into two groups: target group (patients achieving the target dose at V2) and non-target group (patients not achieving the target dose at V2). There was significant difference in the reduction of heart rate from baseline to discharge in the two groups (-4.97 ± 11.90 beats/min vs. -2.70 ± 9.47 beats/min, P = 0.034). There was no significant difference in the proportion of bradycardia that occurred in the two groups at V2 (0 vs. 0, P = 1.000) and V4 (0.81% vs. 0.33%, P = 0.715). There was no significant difference in the proportion of hypotension between the two groups at V2 (0.004% vs. 0.004%, P = 1.000) and V4 (0 vs. 0.005%, P = 0.560). No transient cardiac dysfunction occurred in two groups during the study. A total of five adverse events (1.70%) and one serious adverse event (0.34%) were related to the pathway in target group.@*CONCLUSIONS@#In Chinese ACS patients, the feasibility and tolerability of the MSDP have been proved to be acceptable.

Long-term prognosis of patients with acute non-ST-segment elevation myocardial infarction undergoing different treatment strategies / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In cardiology, it is controversial whether different therapy strategies influence prognosis after acute coronary syndrome. We examined and compared the long-term outcomes of invasive and conservative strategies in patients with non-ST-segment elevation myocardial infarction (NSTEMI) and characterized the patients selected for an invasive approach.</p><p><b>METHODS</b>A total of 976 patients with acute NSTEMI were collected from December 2006 to October 2012 in the First Affiliated Hospital of Dalian Medical University Hospital. They are divided into conservative strategy (586 patients) and invasive strategy (390 patients) group. Unified follow-up questionnaire was performed by telephone contact (cut-off date was November, 2013). The long-term clinical events were analyzed and related to the different treatment strategies.</p><p><b>RESULTS</b>The median follow-up time was 29 months. Mortality was 28.7% (n = 168) in the conservative group and 2.1% (n = 8) in the invasive management at long-term clinical follow-up. The secondary endpoint (the composite endpoint) was 59.0% (n = 346) in the conservative group and 30.3% (n = 118) in the invasive management. Multivariate analysis showed that patients in the conservative group had higher all-cause mortality rates than those who had the invasive management (adjusted risk ratio [RR] = 7.795; 95% confidence interval [CI]: 3.796-16.006, P < 0.001), and the similar result was also seen in the secondary endpoint (adjusted RR = 2.102; 95% CI: 1.694-2.610, P < 0.001). In the subgroup analysis according to each Thrombolysis in Myocardial Infarction risk score (TRS), log-rank analysis showed lower mortality and secondary endpoint rates in the invasive group with the intermediate and high-risk patients (TRS 3-7).</p><p><b>CONCLUSIONS</b>An invasive strategy could improve long-term outcomes for NSTEMI patients, especially for intermediate and high-risk ones (TRS 3-7).</p>

Gender disparity in early death after ST-elevation myocardial infarction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Females with acute myocardial infarction (AMI) have a higher risk of adverse outcomes because of receiving less evidence-based medical care. Our aim was to investigate the gender disparity in early death after ST-elevation myocardial infarction (STEMI) in the current era.</p><p><b>METHODS</b>A total of 1429 consecutive patients with STEMI in the Liaoning district were analyzed. We compared hospital care and cardiac event data by sex for in-patients with acute STEMI within 24 hours of symptom onset.</p><p><b>RESULTS</b>In the emergency reperfusion group (n = 754), in-hospital mortality occurred in 4.2% of the males and 11.2% of the females (P = 0.001). In the non-emergency reperfusion group (n = 675), in-hospital mortality occurred in 13.0% of the males and 22.9% of the females (P = 0.001). Multivariate Logistic regression analysis revealed female sex as an independent risk factor of death for STEMI patients during hospitalization (OR = 1.691, P = 0.007). After controlling for patients who died within 24 hr after admission, female sex was no longer an independent risk factor (OR = 1.409, P = 0.259).</p><p><b>CONCLUSION</b>Female sex was an independent risk factor for in-hospital mortality of STEMI patients, which is explained by an excess of very early deaths.</p>

Inflammation inhibitory effects of sirolimus and paclitaxel-eluting stents on interleukin-1β-induced coronary artery in-stent restenosis in pigs / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Coronary artery in-stent restenosis (ISR) and late stent thrombosis remain as important complications of stenting. The inflammation reactions to sirolimus and paclitaxel-eluting stents were investigated in a swine stenosis model induced by interleukin (IL)-1β.</p><p><b>METHODS</b>Mini pigs (n = 12; 2-3 months old and weighing 25-30 kg) were subjected to thoracotomy. Segments (10 mm) of the mid left anterior descending coronary artery and left circumflex coronary artery were exposed and aseptically wrapped with a cotton mesh soaked with IL-1β (5 µg). After 2 weeks, the animals were anesthetized and quantitative coronary arteriography (QCA) was performed. The stenosis sites were randomized into three groups for stent insertion: a sirolimus-eluting stent (SES) group (Firebird(TM), n = 7), a paclitaxel-eluting stent (PES) group (TAXUS(TM), n = 9), and a bare-metal stent (BMS) group (YINYITM, Dalian Yinyi Biomaterials Development Co., Ltd, China, n = 8). The three different stents were randomly implanted into stenosis segments. Expression of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), P-selectin and vascular cell adhesion molecule-1 (VCAM-1) was determined by reverse transcription-coupled polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>QCA showed severe stenosis in IL-1β treated segments. The SES and PES groups showed lower 1-month angiographic late lumen loss (LLL) within the stent and the lesion compared with BMS (P < 0.05) by follow-up QCA. The SES showed lower LLL than that of PES in reducing 1-month inflammation lesions in pigs by follow-up QCA ((0.15 ± 0.06) mm vs. (0.33 ± 0.01) mm, P < 0.0001). The neointimal hyperplasia areas in SES and PES showed lower than those of BMS (SES (11.6 ± 1.7) mm(2), PES (27.2 ± 1.6) mm(2) vs. BMS (76.2 ± 1.3) mm(2), P < 0.0001). The mRNA expression of MCP-1 by RT-PCR in SES and PES showed lower than that of BMS at 30 days after stenting (SES 0.20 ± 0.03, PES 0.48 ± 0.49 vs. BMS 0.58 ± 0.07, P < 0.05). Levels of VCAM-1 in SES were significantly lower than those of PES and BMS (SES 0.35 ± 0.08 vs. PES 0.65 ± 0.13, BMS 0.70 ± 0.06, P < 0.05). Histochemical immunostaining of vessel walls showed lower inflammatory chemokine MCP-1 expression in the SES and PES groups compared with BMS.</p><p><b>CONCLUSION</b>SESs were superior in reducing 1-month angiographic LLL in inflammation lesions in pigs, strongly suggesting that SESs can suppress inflammatory reactions in ISR at multiple points.</p>

Intracoronary and hypodermic injection of granulocyte colony-stimulating factor improved cardiac function in Swine with chronic myocardial ischemia / 中华心血管病杂志

<p><b>OBJECTIVES</b>To compare the efficacy and feasibility between intracoronary and hypodermic injection of granulocyte colony-stimulating factor (G-CSF) on improving cardiac function in a Swine model of chronic myocardial ischemia.</p><p><b>METHODS</b>Eighteen Swine underwent placement of ameroid constrictor on left circumflex coronary artery. The presence of myocardial ischemia was verified at four weeks after the operation, and the animals were then randomly assigned into three groups (n = 6 each): (1) administration of vehicle (control), (2) hypodermic injection of G-CSF (5 microgxkg(-1)x;d(-1)) for five days (IH), and (3) intracoronary injection of a bonus G-CSF (60 microg/kg) (IC). Coronary angiogram, cardiac MRI, and (18)F-FDG-SPECT/(99m)Tc-SPECT (DISA-SPECT) measurements were performed at pre-administration and at 4 weeks post administration. Global heart function such as left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVSDV) and left ventricular ejection fraction (LVEF), myocardial perfusion, myocardial viability and myocardial infarct area were evaluated. Myocardial vWF, Bcl-2 and Bax expressions were detected by Western blot and RT-PCR.</p><p><b>RESULTS</b>MRI data showed that left ventricular dilation and dysfunction were similarly prevented in IH and IC G-CSF treated animals at eight weeks after the operation. SPECT revealed that both IH and IC G-CSF equally improved the regional contractility of chronic myocardial ischemia and increased myocardial viability. Myocardial infarct size was also reduced after both G-CSF treatments as detected by MRI. Intracoronary injection of G-CSF did not lead to angiogenesis in other organs. G-CSF treatments were also associated with a significant reduction in myocardial apoptosis and significant increase in angiogenesis.</p><p><b>CONCLUSIONS</b>Both intracoronary and hypodermic injection of G-CSF were safe and feasible and could equally improve cardiac function and increase angiogenesis in this Swine model of chronic myocardial ischemia.</p>

Hyperinsulinemia induced immune maturation of human monocyte derived dendritic cells: bridging between diabetes and atherosclerosis / 中华心血管病杂志

<p><b>OBJECTIVE</b>Dendritic cells an hyperinsulinemia are both implicated in the pathogenesis of atherosclerosis. The aim of this study is to explore the effect of high concentration of insulin on the maturation of monocyte-derived dendritic cells (MoDCs) and related signal transduction pathways.</p><p><b>METHODS</b>Human monocytes were purified (over 98%) using Anti-CD14 micro-beads and cultured for 5 days with DC Cellgro medium containing rhGM-CSF (100 microg/L) and rhIL-4 (20 microg/L). Immature DC were then incubated with insulin of various concentrations (0, 1, 10, 100 nmol/L) for 24 hours in the presence or absence of LY294002 (PI3K inhibitor) or PD98059 (MAPK inhibitor). Immunophenotypic expression of CD86 and CD83 were detected using flow cytometry. Endocytosis function of the MoDCs was evaluated using FITC-Dextran and MoDCs secretion IL-12, IFN-gamma and TNF-alpha were measured by ELISA.</p><p><b>RESULTS</b>Insulin induced significantly higher CD83 and CD86 expressions on MoDCs in a dose-dependent manner. The endocytosis function of MoDCs were significantly inhibited and cytokine secretions of IL-12, IFN-gamma and TNF-alpha significantly increased by 10 nmol/L and 100 nmol/L insulin. These effects could be blocked by the LY294002 and PD98059.</p><p><b>CONCLUSION</b>Hyperinsulinemia contributed to atherosclerosis via stimulating immune maturation of MoDCs via both PI3K and MAPK pathways.</p>

Evaluation of myocardial viability with 201Tl/18F-FDG DISA-SPECT technique in patients with acute myocardial infarction after emergent intracoronary autologous bone marrow mononuclear cells transplantation / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the myocardial viability with (201)Tl/(18)F-FDG DISA-SPECT technique in patients with acute myocardial infarction underwent emergent intracoronary autologous bone marrow mononuclear cells (BM-MNC) transplantation.</p><p><b>METHODS</b>Patients with first acute myocardial infarction underwent emergent percutaneous coronary intervention (PCI) were randomized in a 1:1 ratio to either intracoronary transplantation of autologous BM-MNC (n = 20) or to sodium chloride concluding heparin (control, n = 20) via a micro infusion catheter group immediately after PCI. Change in global left ventricular function (LVEF measured by echocardiography) and the myocardial viability detected by (201)Tl/(18)F-FDG DISA-SPECT from baseline and 6-months post transplantation were analyzed.</p><p><b>RESULTS</b>Left ventricular ejection fraction (LVEF) was improved in both groups and the absolute increase (DeltaLVEF) in BM-MNC group was significantly higher than that in control group (7.6% +/- 2.8% vs. 3.0% +/- 2.8%, P < 0.001). In addition, the absolute decrease of myocardial infusion defect detected by (201)Tl SPECT was more significant in BM-MNC group than that in control group (6.7% +/- 3.0% vs. 2.6% +/- 2.6%, P < 0.001) and the number of mismatched segments (indicating viable myocardium) detected by (18)F-FDG SPECT in border zone was also significantly higher in BM-MNC group than that in control group.</p><p><b>CONCLUSION</b>Improved myocardial viability and reduced myocardial infusion defect post emergent intracoronary transplantation of autologous BM-MNC in patients with acute myocardial infarction could be detected by (201)Tl/(18)F-FDG DISA-SPECT technique.</p>

In vivo cardiac magnetic resonance imaging of superparamagnetic iron oxides-labeled mesenchymal stem cells in swines / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the feasibility of magnetic resonance imaging (MR) on detecting transplanted nanometer small superparamagnetic iron oxides (SPIO) labeled mesenchymal stem cells (MSCs) in swine model with acute myocardial infarction (MI).</p><p><b>METHODS</b>MSCs isolated from swine were incubated with nanometer SPIO for 24 hours and the third-passage MSCs were labeled with DNA dye 4'-6-diamidino-2-phenylindole (DAPI) and aliphatic red fluorescent dye PKH(26)-GL. Presence of small particles of SPIO in MSCs was assessed by Prussian Blue staining and electron microscopy. Three animals in each group received SPIO-labeled MSCs (5 x 10(5); 1 x 10(6); 2 x 10(6)) and MSCs without SPIO (1 x 10(6)) injections into the infarcted myocardium approximately 1 hour following left anterior descending coronary artery. MRI (1.5-T) was performed 20 to 24 hours post infarction in all animals and the animals were subsequently sacrificed for histology 1 hour post MRI.</p><p><b>RESULTS</b>In vitro Prussian Blue staining and electron microscopy examination revealed numerous iron particles in the cytoplasm of MSCs. Low signal intensity spots with the scanning T(2)(*)WI-Flash 2d sequence were detected in all SPIO-MSCs but not in SPIO-negative-MSCs injected myocardial sites in vivo with the clinical 1.5 T scanner. Prussian blue, DAPI and PKH(26) positive cells were detected histologically in sections corresponding to low signal intensity spots area shown on MRI.</p><p><b>CONCLUSION</b>Magnetically labeled MSCs transplanted in myocardial ischemia area of swine can be visualized in vivo with a clinical 1.5-T MRI and could be used for tracking SPIO-MSCs clinically.</p>

Observation on the safety: clinical trail on intracoronary autologous bone marrow mononuclear cells transplantation for acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the safety of autologous bone marrow mononuclear cell (BM-MNCs) transplantation by intracoronary infusion in patients with acute myocardial infarction (AMI).</p><p><b>METHODS</b>One hundred and eighty-four patients with AMI treated with percutaneous coronary intervention (PCI) were randomized in a 1:1 way to either intracoronary transplantation of autologous BM-MNCs (n = 92) right after PCI or to sodium chloride concluding heparin (controlled, n = 92) via a micro infusion catheter. In the process of the intracoronary infusion of BM-MNCs, the complications should be recorded, which were aberration reflect (including of pale, syncope, nausea, hypotension and shock), deterioration of angina or heart failure, arrhythmias (including of bradycardia, sinus arrest or atrial ventricular block or ventricular fibrillation), embolism etc. Body temperature, blood pressure and heart rates should be monitored during the first week after transplantation. Holter, coronary angiography and ultrasonic cardiography were performed at the designed time points. Main heart accidents, restenosis and tumor were recorded during 2-years follow up.</p><p><b>RESULTS</b>During the period of bone marrow puncture and intracoronary infusion of BM-MNCs, few patients occurred pale, dizziness, bradycardia and hypotension, which were transient and due to vagus reflect. No stem cell-related arrhythmias, deterioration of angina were noted. In BM-MNCs group one patient developed in-stent reocclusion in one week after transplantation, five developed in-stent restenosis during further follow-up 30 months, which were similar with control group. There were no deaths, major adverse cardiac events, tumor and other late adverse events during follow-up period in both groups.</p><p><b>CONCLUSION</b>Intracoronary transplantation of autologous BM-MNCs in the acute phase after AMI is feasible and seems safe in the 30 months of follow-up.</p>

Transplantation of autologous bone marrow mononuclear cells on patients with idiopathic dilated cardiomyopathy: early results on effect and security / 中华心血管病杂志

<p><b>OBJECTIVE</b>The aim of this study is to identify short-term result of cell transplantation in idiopathic dilated cardiomyopathy (IDC) patients who were treated by intracoronary transplantation of autologous mononuclear bone marrow cells (BMCs) in addition to standard therapy.</p><p><b>METHODS</b>Based on given standard therapy, eighteen patients with idiopathic dilated cardiomyopathy were enrolled and divided into transplantation group and control group. The clinical characteristics of two groups were comparable. Among these patients, 10 patients were performed percutaneous coronary autologous BMCs transplantation. Blood routine test, hepatic function, renal function, glucose, triglyceride (TG), cholesterol, low density cholesterol (LDL), high density cholesterol (HDL), uric acid (UA) and high sensitive C-reactive protein (hsCRP) were measured at the time point of pre-operation and some time after transplantation. All patients were monitored under ultrasonic cardiography, Holter, six-minute-walk test and magnetic resonance imaging over a period of at least 6 months. Annual hospital days were recorded during two-year follow-up.</p><p><b>RESULTS</b>Blood routine test, hepatic function, renal function, glucose, TG, cholesterol, LDL, HDL, UA and hsCRP had no significant differences among 48 hours, 3 months and 6 months after transplantation compared with control and pre-transplantation (P > 0.05). Six-minute-walk distance elevated significantly six months after BMCs transplantation compared with control and pre-transplantation [(494.3 +/- 62.8) m vs (307.2 +/- 75.0) m, (321.5 +/- 63.7) m, P < 0.05]. Left ventricular ejection fraction (LVEF) and the sizes of LVEDd had no significant changes compared with that of control and pre-transplantation (P > 0.05). Myocardium lesion area measured by (MRI) seemed decrease in transplantation group compared with that of control and pre-operation [(4.96 +/- 0.47) cm(2) vs (5.12 +/- 0.54) cm(2), (5.02 +/- 0.39) cm(2), P > 0.05], but there was no significance. None of proarrhythmias and side effects had been observed around transplantation and 2 years follow-up. There was no significant difference in survival between two groups in 2 years follow-up. Interestingly, annual hospital day in BMCs transplantation patients was significantly shorter than that in control group [(30.2 +/- 11.2) d vs (43.6 +/- 9.8) d, P < 0.05].</p><p><b>CONCLUSIONS</b>Autologous bone marrow mononuclear cells transplantation can prolong six-minute-walk, decrease re-hospitalization rate, elevate exercise ability and help to improve cardiac function in patients with IDC. In addition, it was demonstrated that cell transplantation is safe.</p>

Effects and mechanism of hyperglycemia on development and maturation and immune function of human monocyte derived dendritic cells / 中华心血管病杂志

<p><b>OBJECTIVE</b>Dendritic cells play an important role in the pathogenesis of atherosclerosis. To explore the effects of hyperglycemia on the maturation and immune function of human monocyte derived dendritic cells (MDCs).</p><p><b>METHODS</b>Immature MDCs were cultured in RPMI1640 medium with either 5.5 mmol/L D-glucose (NG), 25 mmol/L D-glucose (HG) or 5.5 mmol/L D-glucose + 19.5 mmol/L mannitol (HM) in the absence or presence of 30 mmol/L N-acetylcysteine [NAC, a reactive oxygen species inhibitor (ROS)] for 48 hours. FACS was used to investigate the MDCs immunophenotypic expression. Immune function was evaluated by allogeneic mixed T lymphocyte reaction and measurement of cytokine levels from culture supernatants. Intracellular ROS production in MDCs was also measured by 2', 7'-dichlorodihydrofluorescein (DCF, 10 micromol/L) fluorescence using confocal laser-scanning microscopy techniques.</p><p><b>RESULTS</b>Compared with NG and HM treated MDCs, the expression of maturation markers such as CD1a, HLA-DR, CD83, CD86 were significantly upregulated, allogeneic T cells proliferation as well as the cytokines secretions (IL-2, IL-12, IL-10 and IFN-gamma) significantly increased in HG treated MDCs. Intracellular ROS production in MDCs was also significantly increased and all these stimulatory effects of HG could be partially attenuated by NAC.</p><p><b>CONCLUSION</b>High glucose promote the maturation of MDCs and augment their capacity to stimulate T-cell proliferation and cytokine secretions at least in part through enhancing intracellular ROS generation. These stimulating effects of high glucose on MDCs maturation may be one of the mechanisms of accelerated atherosclerosis found in patients with diabetes.</p>

The role of first pass and delayed contrast-enhancement magnetic resonance imaging in patients with myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the role of contrast-enhancement magnetic resonance imaging (CeMRI) in patients with myocardial infarction (MI).</p><p><b>METHODS</b>There were twenty-three patients enrolled in this study. After dynamic observation, there were 20 patients who were diagnosed as MI. All those patients underwent coronary artery angiography and CeMRI. MRI was performed with a 1.5-T magnet (AVANTO, SIMENS). After tagged images were acquired, the patients received an intravenous bolus of 0.1 mmol/kg Gd-DTPA at a rate of 5 ml/s. A first-pass perfusion scan was acquired simultaneously with a bolus injection. A second bolus of 0.3 mmol/kg Gd-DTPA was given following the first-pass images. Delayed images were acquired 5 minutes after the second bolus by using an inversion-recovery prepared gated fast-gradient echo-pulse sequence.</p><p><b>RESULTS</b>Hypoenhancement was seen in 20 patients at the first-pass perfusion at the myocardial infarction site, while hyperenhancement was seen at delayed CeMRI. Myocardial infarction area in delayed CeMRI was 16.58% +/- 9.73%, which was correlated positively with peak CK and cTnT (r = 0.821, P < 0.01 and r = 0.565, P < 0.05), respectively. The ejection fraction (EF) detected by MRI was 0.46 +/- 0.13, while the left ventricular EF (LVEF) detected by left ventriculography was 0.49 +/- 0.16. There was no difference between two parameters.</p><p><b>CONCLUSIONS</b>CeMRI may play an important role in the diagnosis and prognosis of patients with MI.</p>

Stem cells transplantation for ischemic heart disease / 中国医学科学院学报

At present, no effective therapeutic option for ischemic heart disease is available. The majority of the data on stem cell transplantation coming from preclinical animal studies and clinical research in small scale demonstrate that it may improve cardiac function. However, serious questions about its safety have yet to be answered.

In vitro and in vivo MR imaging of SHU 555A-labelled swine bone marrow mesenchymal stem cells / 介入放射学杂志

Objective To detect the feasibility of magnetically labeled swine bone marrow mesenehymal stem cells(MSCs)with SHU 555A combined with poly-L-arginine(PLL),under MR imaging in vitro and in vivo.Methods Swine mesenehymal stem cells were isolated and culture-expanded 3 passages in vitro,then magnetically labeled by incubation with SHU 555A(25?g Fe/ml,Resovist,Schering)for 24 hours with 750 ng/mL poly-L-lysine(PLL;average MW_275 kDa)added 1 hour before incubation.Cellular iron incorporation and detention at 0 d,4 d,8 d,12 d,16 d,20 d after labeling was qualitatively assessed using Prussian blue and quantified at atomic absorption spectrometry.Cell viability was assessed by trypan-blue exclusion test.Cell suspensions underwent MR imaging with T_1-and T_2-weighted spin-echo and fast field-echo sequences on a clinical 1.5 T MR system.At last,1?10~6 SHU 555A labeled and unlabeled MSCs were transextracardially implanted into the infracted and normal myocardium approximately 2 week following the ligation of left anterior descending coronary artery in 1 swine respectively,and finally performed 1.5-T MRI within 1 week after infarction.Results①Intracytoplasmic particles stained with Prussian blue stain were detected for all cells with mean cellular iron content of(13.13?2.30)pg per cell.With division of stem cells, the stained particles decreased gradually with iron content(0.68?0.20)pg per cell.at 16 days after labeling, approximately to the prelabeled baseline values.(0.21?0.06)pg per cell(P＞0.05).The viability of the labeled cells at various time points were not significantly different with that of nonlabeled cells(P＞0.05).②MR images showed signal intensity changed most obviouly in T2*WI in vitro.The percentage change of signal intensity increased with increasing cell numbers,and decreased with the time.As few as 5?10~4-1?10~5 cells could be detected by using this approach.③Two injected sites containing MR-MSCs were detected in vivo,presentingas low signal intensity areas with the T_2*WI scanning sequence.Conclusion Swine bone marrow MSCs can be labeled with SHU555A-PLL and depicted with a standard 1.5-T MR imager in vitro and in vivo.(J lntervent Radiol,2007,16:115-121)