Objective: To compare the efficacy of off-pump minimally invasive cardiac surgery (MICS) via a single left intercostal space incision with median sternotomy multi-vesselcoronary artery bypass grafting (CABG). Methods: Patients who were diagnosed with multi-artery coronary artery disease (CAD) in the Ward 10 of the Department of Cardiac Surgery, Beijing Anzhen Hospital Affiliated to Capital Medical University and underwent CABG from July 2019 to January 2022 were retrospectively collected. All the patients were divided into MICS group and conventional CABG group according to the surgical methods. The perioperative outcomes were compared between thetwo groups, including intraoperative blood loss, postoperative 24 h thoracic drainage volume, ventilation duration, length of stay (LOS) in intensive care unit (ICU) and total LOS in hospital. Intraoperative blood flow of graft vesselswas measured by transit-time flow measurement (TTFM) after vascular anastomosis, and mean flow (MF) and pulsatile index (PI) were compared between the two groups. Results: A total of 444 patients were in the final analysis, with 351 males and 93 females, and the mean age of (62.0±8.9) years. There were 179 patients in MICS group and 265 cases in conventional CABG group, respectively. There were no statistically significant differences in the preoperative profiles between the two groups (all P>0.05) except that younger age [(60.7±9.3) years vs (62.8±8.5) years, P=0.017] and lower proportion of female [10.1% (18/179) vs 28.3% (75/265), P<0.001] were detected in MICS group. Likewise, there was no significant difference in the number of graft vessels between MICS group (3.18±0.74) and conventional CABG group (3.28±0.86) (P=0.234). Compared with those in conventional CABG group, patients in MICS group showed longer operation duration [ (5.10±1.09) h vs (4.33±0.86) h], fewer intraoperative blood loss [500 (200, 700) ml vs 700 (600, 900) ml], fewer postoperative 24 h thoracic drainage volume [300 (200, 400) ml vs 400 (250, 500) ml], shorter postoperative ventilation duration [15.0 (12.0, 17.0) h vs 16.5 (12.5, 19.0) h, P<0.001], LOS in ICU [18.0 (15.0, 20.0) h vs 20.0 (16.0, 23.0) h, P<0.001] and total LOS in hospital [(12.6±2.7) d vs (14.5±3.9) d, P<0.001]. MI and PI of graft vessels were similar between the two groups (both P>0.05). Moreover, there were no significant differences in major perioperative complications (i.e., repeat thoracotomy, incision infection, stroke) and mortality between the two groups (all P>0.05). Conclusion: MICS is an alternative treatment for patients with multi-vessel CAD with better perioperative outcomes compared with conventional CABG.

目的 通过使用标准的化学定义和基于小分子诱导方案(chemically defined medium,3 components,CDM3)获得人诱导多能干细胞分化来源的心肌细胞(human induced pluripotent stem cell?derived cardiomyocytes,hiPSC?CMs),进一步对其施加机械牵张,探讨机械牵张对hiPSC?CMs成熟的影响及潜在机制.方法 复苏、培养和鉴定hiPSCs后,将hiPSCs接种到覆有基质胶的传统培养皿上.24 h后在荧光显微镜下通过DAPI荧光观察细胞生长情况,并通过八聚体结合转录因子4(octamer?binding transcription factor 4,OCT4)荧光进行hiPSCs干性鉴定,在细胞汇合度达到80％时更换CDM3分化培养基,分化6 d后将获得的hiPSC?CMs分为对照组和机械牵张组,拉伸结束后重新种板培养24 h后在荧光显微镜下通过DAPI荧光观察细胞生长情况,通过心肌肌钙蛋白T(cardiac troponin T,cTnT)和肌球蛋白轻链2V(myosin light chain 2V,MLC2V)荧光进行hiPSC?CMs心肌细胞标志物鉴定,Piezo1荧光进行潜在机制研究.结果 hiPSCs培养24 h免疫荧光显示:OCT4发出绿色荧光,hiPSCs保持干性.DAPI发出蓝色荧光:细胞呈克隆生长,细胞形态均一.机械牵张结束后重新种板培养,24 h后免疫荧光显示机械牵张组较对照组心肌标志物cTnT和MLC2V表达增高(P<0.05);机械牵张组较对照组机械敏感型离子通道Piezo1蛋白表达增高(P<0.05).结论 机械牵张可以促进人诱导多能干细胞分化来源心肌细胞的成熟,这可能与Piezo1蛋白表达增高有关.

BACKGROUND:Myocardial infarction is a serious clinical disease with high mortality and poor prognosis. Cardiomyocytes (CMs) have limited regeneration abilities after ischemic injury. Their growth and differentiation can be enhanced by contact co-culture with stem cells.OBJECTIVE:The aim was to study the contact co-culture of Dil-labeled bone marrow mesenchymal stem cells (BMSCs) and CMs for inducing differentiation of CMs from stem cells for treating myocardial infarction.METHODS:After contact co-culture, the differentiation of BMSCs into CMs was analyzed qualitatively by detecting myocardial markers (cardiac troponin T and α-smooth muscle actin) using immunofluorescence and quantitatively using flow cytometry. To examine the mechanism, possible gap junctions between BMSCs and CMs were analyzed by detecting gap junction protein connexin 43 (C×43) expression in BMSCs using immunofluorescence. The functionality of gap junctions was analyzed using dye transfer experiments.RESULTS:The results revealed that BMSCs in contact with CMs exhibited myocardial markers and a significant increase in differentiation rate (P < 0.05); they also proved the existence and function of gap junctions between BMSCs and CMs.CONCLUSIONS:It was shown that contact co-culture can induce Dil-labeled BMSCs to differentiate into CM-like cells and examined the principle of gap junction-mediated signaling pathways involved in inducing stem cells to differentiate into cardiomyocytes.

Background The perioperative outcomes following off-pump multi-vessel minimally invasive surgery (MICS) coronary artery bypass grafting (CABG) via a single left intercostal space incision has not been well evaluated. Method From July 2019 to January 2022, a total of 444 patients with multi-vessel coronary artery disease (CAD) were enrolled and divided into MICS ( n = 179) and sternotomy CABG ( n = 265). Perioperative outcomes were compared between these two groups, including intraoperative blood loss, postoperative first 24 h drainage, ventilation duration, length of stay (LOS) in ICU and total LOS in hospital. Intraoperative blood flow of graft vessels were measured by transit-time flow measurement after vascular anastomosis and mean flow (MF) and pulsatile index (PI) were compared. Results There were no significant differences in preoperative profiles between these two groups except younger and lower proportion of female in MICS. No significant difference in the number of graft vessels was observed between MICS (3.18 ± 0.74) and sternotomy CABG (3.28 ± 0.86). Compared to sternotomy CABG, patients with MICS showed longer operation duration [(4.33 ± 0.86) h versus (5.10 ± 1.09) h], fewer intraoperative blood loss [700 (600, 900) mL versus 500 (200, 700) mL], fewer postoperative first 24 h drainage [400 (250, 500) mL versus 300 (200, 400) mL], shorter postoperative ventilation duration [16.5 (12.5, 19.0) h versus 15.0 (12.0, 17.0) h], LOS in ICU [20.0 (16.0, 23.0) h versus 18.0 (15.0, 20.0) h] and total LOS in hospital [(14.5 ± 3.9) d versus (12.6 ± 2.7) d] (all p < .001). MI and PI of graft vessels were similar and no significant differences in major perioperative complications and mortality were observed between MICS and sternotomy CABG (all p > .05). Conclusion Off-pump multi-vessel MICS may be an alternative treatment for patients with multi-vessel CAD with better perioperative outcomes than sternotomy CABG.

To promote the differentiation of human-induced pluripotent stem cells (hiPSCs) into myocardium through a standard chemically defined and small-molecule-based induction protocol (CDM3), and preliminarily prepare myocardial patches that provide experimental data and theoretical support for further maturation through other in vitro experiments and safety studies in vivo. After resuscitation, culture, and identification of hiPSCs, they were inoculated onto Matrigel-coated polycaprolactone (PCL). After 24 h, cell growth was observed by DAPI under a fluorescence microscope and the stemness of hiPSCs was identified by OCT4 fluorescence. After fixation, scanning electron microscopy was performed to observe the morphology of cells on the patch surface. On days 1, 3, 5, and 7 of culture, cell viability was determined by Cell Counting Kit-8 (CCK-8) assay and a curve was drawn to observe cell growth and proliferation. After co-culture with Matrigel-covered PCL for 24 h, hiPSCs were divided into control and CDM3 groups, and cultured for an additional 6 d. On the eighth day, cell growth was observed by DAPI under a fluorescence microscope, hiPSC stemness was identified by OCT4 fluorescence, and cardiomyocytes were identified by cardiac troponin T (cTnT) and α-actin expression. hiPSCs co-cultured with Matrigel-covered PCL for 24 h emitted green fluorescence indicating OCT4, showing that hiPSCs maintained their stemness on Matrigel-covered PCL scaffolds. DAPI emitted blue fluorescence, indicating that cells grew clonally with uniform cell morphology. Scanning electron microscopy showed that hiPSCs adhered and grew on PCL covered with Matrigel, with clearly visible cell outlines indicating normal morphology. Assessment of cell viability by the CCK-8 method showed that hiPSCs proliferated and grew on PCL scaffolds covered with Matrigel. After 6 d of culture, immunofluorescence showed that control group hiPSCs highly expressed the stem cell marker OCT4 but not myocardial markers cTnT or α-actin. In contrast, notable expression of myocardial markers cTnT and α-actin but not OCT4 occurred in the CDM3 group. hiPSCs can proliferate and grow on PCL scaffolds covered with Matrigel. Under the influence of CDM3, hiPSCs differentiated into cardiomyocyte-like cells, allowing the preliminary preparation of myocardial patches that can provide a better method for clinical treatment of myocardial infarction.

Objective:Polycaprolactone (PCL) film was co-cultured with 1, 1′-dioctadecyl-3, 3, 3′, 3′-tetramethylindocarbocyanine perchlorate (DiI) labeled bone mesenchymal stem cells (BMSCs) to prepare cell patch.Methods:Clean grade SD rats were selected as experimental objects, BMSCs were isolated and cultured, and the surface markers were identified by flow cytometry. After the BMSCs were cultured for 3 passages, the BMSCs were stained with DiI dye, and the BMSCs DiI and PCL biomaterial film were co-cultured. After 24 h, the cell growth was observed under fluorescence microscope, and cells were fixed for scanning under electron microscope. The cell proliferation was detected by CCK-8 at 1, 4, 7, 10 days of culture. The measurement data conforming to normal distribution were expressed as mean±standard deviation ( ± s). One way ANOVA was used for comparison among groups, and LSD analysis was used for pairwise comparison. Results:BMSCs were strongly positive for CD90, CD44H, but negative for CD11b/c, CD45. Under fluorescence microscope, BMSCs DiI showed red light, fusiform or polygonal. Under the scanning electron microscope, the cell patch formed by co-culture of PCL film and DiI-BMSCs had a large number of cells on the surface and normal cell state. CCK-8 assay showed that the absorbance ( A) value on the first day, 4th day, 7th day and 10th day was 0.330±0.025, 0.620±0.012, 1.033±0.144 and 1.223±0.133, respectively. There was significant difference in A value among the time points ( F=66.441, P<0.05). Conclusion:PCL film can be used as an in vivo tracer scaffold material for stem cell therapy.

To provide better treatment of myocardial infarction, DiI-labeled bone marrow mesenchymal stem cells (BMSCs) were contact co-cultured with cardiomyocytes (CMs) on polycaprolactone (PCL) film to prepare myocardial patches. BMSCs from Sprague Dawley rats were isolated, cultured, and characterized for expression of surface markers by flow cytometry. CMs were isolated from suckling rats. After BMSCs were cultured for three generations, they were labeled with DiI dye. DiI-labeled BMSCs were co-cultured with CMs on PCL film in the experimental group, while CMs were replaced with the same amount of unlabeled BMSCs in the control group. After 24 h, cell growth was observed by light microscopy and cells were fixed for scanning electron microscopy (SEM). After 7 d of co-culture, cells were stained for immunofluorescence detection of myocardial markers cardiac troponin T (cTnT) and α-actin. Differentiation of BMSCs on PCL was observed by fluorescence microscopy. The efficiency of BMSC differentiation into CMs was analyzed by flow cytometry on the first and seventh days of co-culture. CMs were stained with calcein alone and contact co-cultured with DiI-labeled BMSCs on PCL film to observe intercellular dye transfer. Finally, cells were stained for immunofluorescence detection of connexin 43 (Cx43) expression and to observe the relationship between gap junctions and contact co-culture. BMSCs were identified by flow cytometry as strongly positive for CD90 and CD44H, and negative for CD11b/c and CD45. After co-culture for 24 h, cells were observed to have attached to PCL by light microscopy. Upon appropriate excitation, DiI-labeled BMSCs exhibited red fluorescence, while unlabeled CMs did not. SEM revealed a large number of cells on the PCL membrane and their cell state appeared normal. On the seventh day, some DiI-labeled BMSCs expressed cTnT and α-actin. Flow cytometry showed that the rate of stem cell differentiation in the experimental group was significantly higher than the control group on the seventh day (20.12% > 3.49%, P < 0.05). From the second day of co-culture, immunofluorescence staining for Cx43 revealed green fluorescent puncta in some BMSCs; from the third day of co-culture, a portion of BMSCs exhibited green fluorescence in dye transfer tests. Contact co-culture of DiI-labeled BMSCs and CMs on PCL film generated primary myocardial patches. The mechanism by which contact co-culture promoted differentiation of the myocardial patch may be related to gap junctions and gap junction-mediated intercellular signaling pathways.

目的 初步探讨中性粒细胞淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)与非体外循环冠状动脉旁路移植术(off-pump coronary artery bypass grafting,OPCABG)术后新发心房颤动(atrial fibrillation,AF)的相关性.方法 回顾性分析2021年1月1日至12月31日135例由单一治疗组行OPCABG患者的临床资料,根据术后是否发生AF分为AF组与非AF组,分析患者的性别、年龄、EuroSCOREⅡ评分、手术前后超声学相关指标、术前及术后第1 d的NLR,分析不同组别NLR值及其他因素与术后新发AF之间的关系.结果 两组之间在年龄、术前EuroSCOREⅡ评分及术后NLR存在显著性差异(P<0.05),AF组的年龄[(65.7±6.7)岁比(61.7±9.1)岁]、EuroSCOREⅡ评分[(2.9±2.5)分比(2.2±1.2)分]及术后NLR水平[(14.7±10.8)mm比(11.3±5.7)mm]均高于非AF组.术后平均随访时间为(6.9±3.3)个月,无新增死亡病例,1例患者术后半年因"病窦综合征"行人工起搏器置入,其余患者无再发AF.结论 NLR作为一种新型的炎症评价指标,与AF的发生密切相关,术后NLR越高,OPCABG术后发生AF的概率越高.

目的:总结88例完整迷宫Ⅳ手术治疗心脏疾病合并心房颤动的近中期临床疗效.方法:2017年6月至2021年12月期间,应用双极射频钳+单极射频笔在进行心外科手术同时完成迷宫Ⅳ手术88例合并心房颤动的患者.所有手术均在体外循环下完成,并行循环下先完成右心房的射频消融,心脏停跳后再完成左心房的射频消融,对于双极消融不能达到的二尖瓣峡部及冠状静脉窦等部位应用单极笔进行"补消",术后3、6、12、18及24个月分别进行随访,随访终点事件为死亡,终点时间为术后24个月或2021年12月31日.随访内容为主要心脑血管事件、24h动态心电图(Holter),以Holter出现超过15s的心房颤动或心房扑动判定为心房颤动复发.结果:全组88例患者,2例死亡,1例为术后严重低心排,1例出现感染性休克;术后3、6、12、18及24个月的心房颤动免除率分别为93.0％、87.2％、79.4％、74.1％及72.0％.结论:迷宫Ⅳ手术作为一种外科治疗心房颤动的手段,在消除心房颤动,恢复窦性心律方面具有良好的近中期疗效,而手术成功的关键是标准的消融线路,特别是峡部和冠状静脉窦的消融.

The low seeding rate and survival rate of transplanted cells is one of the difficulties of stem cell transplantation in the treatment of myocardial infarction. By culturing human induced pluripotent stem cells (hiPSCs) on Matrigelcoated polycaprolactone (PCL) in vitro to mimic the natural extracellular matrix in terms of composition and structure, we investigated the effect of Matrigel on the adhesion and proliferation of hiPSCs on PCL. After resuscitation, culture, and identification of hiPSCs, the cells were seeded on Matrigel-coated plastic, PCL, or Matrigel-coated PCL. After 24 h, cell growth was observed by 4,6-diamidino-2-phenylindole (DAPI) fluorescence under a fluorescence microscope and hiPSC stemness was identified by OCT4 fluorescence. After fixation, scanning electron microscopy was performed to observe the surface morphology of cell patches. A growth curve was used to assess cell proliferation. The results showed that hiPSCs can be cultured on PCL and Matrigel-coated PCL to prepare cell patches. Matrigel-coated PCL provides a better environment for cell growth, adhesion, and proliferation. Thus, Matrigel is effective for the culture of hiPSCs on polycaprolactone to prepare cell patches.

BACKGROUND:In stem cell therapy, due to the lack of an effective carrier, a large number of transplanted stem cells are lost and die. Therefore, finding a suitable carrier has become a further direction of stem cell therapy.OBJECTIVE:In research on the co-culture of polycaprolactone (PCL) with 1,1'-Dioctadecyl-3,3,3',3'- tetramethylindocarbocyanine perchlorate (DiI) labeled bone marrow mesenchymal stem cells (BMSCs), we observe the effect of materials on the growth and proliferation of DiI labeled stem cells, and the effect of DiI labeling on patch preparation, so as to find a kind of biomaterial suitable for the growth and proliferation of BMSCs, and find a suitable cell carrier for stem cell therapy of myocardial infarction and in vivo tracing.METHODS:Clean grade Sprague Dawley rats were selected as experimental objects, BMSCs were isolated and cultured, and the surface markers were identified by flow cytometry. After the BMSCs were cultured for 3 passages, the BMSCs were stained with DiI dye, and the BMSCs DiI and PCL biomaterial film were co-cultured. After 24 hours, the cell growth was observed under fluorescence microscope, and fixed for scanning under electron microscope. The cell proliferation was detected by CCK-8 at 1, 4, 7, 10 days of culture. The measurement data conforming to normal distribution are expressed in the form of mean ± standard deviation (X¯± s). One way ANOVA was used for comparison among groups, LSD analysis was used for pairwise comparison. The difference was statistically significant (P < 0.05).RESULTS:BMSCs were strongly positive for CD90, CD44H, but negative for CD11b/c, CD45. Under fluorescence microscope, BMSCs DiI showed red light, fusiform or polygonal. Under the scanning electron microscope, the cell patch formed by co-culture of PCL film and DiI-BMSCs had a large number of cells on the surface and normal cell state. CCK-8 assay showed that the OD value on the first day was 0.330 ± 0.025; The OD value was 0.620 ± 0.012 on the 4th day, 1.033 ± 0.144 on the 7th day and 1.223 ± 0.133 on the 10th day. There was significant difference among the time points (P < 0.05).CONCLUSIONS:The cell patch made of PCL film and DiI labeled BMSCs can survive and proliferate on the surface, so it can be used as a scaffold material for stem cell therapy in vivo.

Objective:To investigate the effect of hypoxic microenvironment on the co-culture of mouse bone marrow mesenchymal stem cells (mMSCs) with poly (3-hydroxybutyrate-co-4-hydroxyhexanoate [P (3HB-co-4HB)] material to form a myocardial patch.Methods:mMSCs were extracted, P (3HB-co-4HB) and mMSCs were co-cultured into cell supplements, and normoxia group and hypoxia group were set up. The cell proliferation was examined by by cell counting kit-8 (CCK-8) assay. The scanning electron microscope (SEM) was used to observe the survival, adhesion and growth of the patch. After the addition of the inducer 5-azacytidine, the expression of cardiac troponin T (cTnT) was detected by immunofluorescence. The expression of hypoxia-inducible factor-1α (HIF-1α) mRNA and protein was detected by real-time quantitative polymerase chain reaction (PCR) and Western blotting respectively. The Student’s t test was used to determine significant differences between the two groups. Results:The A value in the hypoxic group measured by CCK-8 assay (0.349±0.038) was significantly higher than that in the normoxic group (0.308±0.025, t=2.420, P<0.05), which was observed by SEM. The number of cells on P (3HB-co-4HB) material in the oxygen group was more, the adhesion between the cells and the material was firm, and the cell morphology was normal. Immunofluorescence showed that the expression of cTnT in the hypoxic group was significantly higher than in the normoxic group. Significant upregulation of HIF-1α mRNA was observed by real-time quantitative PCR ( P<0.05). As compared with normoxic group (0.47±0.05), the relative expression of HIF-1α protein in hypoxia group (0.63±0.06) was significantly increased ( P<0.05). Conclusion:Compared with normoxic conditions, hypoxic microenvironment can promote the adhesion, survival, proliferation and differentiation of mMSCs on P (3HB-co-4HB) materials, and form a more effective myocardial patch, which may be related to the activation of the HIF-1α pathway.

目的:对比研究非体外循环下冠状动脉旁路移植术(OPCABG)后,分别运用单抗(阿司匹林)与双抗(阿司匹林+氯吡格雷)抗血小板治疗后,对远期乳内动脉桥血管通畅率的影响.方法:回顾性分析2005年01月至2005年12月,在安贞医院心脏外科固定手术组行OPCABG并顺利出院的230例患者的临床资料,并对其进行随访.结果:随访时间为150个月,随访期内心脏相关死亡54例(16.4％).两组前降支通畅率分别为65.8％、66.4％(P＞0.05).结论:对于OPCABG的患者,无论给与双抗或单抗,其远期效果并无明显差异,但短期内前降支通畅率变化趋势,双抗组优于单抗组.

目的:总结Cox迷宫Ⅳ手术治疗心脏疾病合并心房颤动的近期临床效果.方法:2017年6月至2018年9月期间,本治疗小组连续26例心脏疾病合并心房颤动患者实施心脏手术同期行Cox迷宫Ⅳ手术治疗心房颤动.手术经正中开胸,在体外循环下进行,在完成心内手术之前实施右心房及左心房的射频消融术,右心房射频在升主动脉阻断前、心脏跳动下进行,左心房射频则在心脏停跳下,经房间沟入路进行,所有患者均进行左心耳干预(包括结扎、缝扎、切除缝合及内部缝合).结果:全组26例患者术后院内死亡1例(3.8％),出院时心房颤动复发4例(16.0％).体外循环时间(174.4±39.5)min,主动脉阻断时间(122.7±33.3)min.术后合并哮喘1例,三尖瓣重度反流1例,反复胸腔积液1例,电复律1例.超声心动图结果显示,26例患者术后的左心房内径、左心室舒张末期内径及左心室射血分数较术前均有下降(P均<0.01).以术后3个月作为术后首次随访时间节点,25例患者进行24小时动态心电图随访,其中4例(16.0％)心房颤动复发,其余21例(84.0％)为窦性心律,偶发房性早搏及室性早搏.结论:Cox迷宫Ⅳ手术作为外科治疗心房颤动的一种术式,心房颤动转复率高,近期疗效肯定,安全可行,值得推广.

Herein we researched the effects of a hypoxic microenvironment on bone marrow mesenchymal stem cells (BM-MSCs) on poly 3-hydroxybutyrate-co-4-hydroxybutyrate [P(3HB-co-4HB)] and present a theoretical basis for development of cell transplantation. Mouse bone marrow mesenchymal stem cells were isolated by whole bone marrow culture and surface antigens were analyzed by flow cytometry of passage 5 cells. P(3HB-co-4HB) and bone marrow mesenchymal stem cells were prepared as stem cell patches randomly divided into normoxia (control, 20% oxygen) and hypoxia (3% oxygen) groups. After 24 h, the patch was used for experiments. Cell proliferation was determined by CCK-8 assays. Adhesion, survival, and growth of cells on patches were observed by scanning electron microscopy. Expression of hypoxia-inducible factor-1α (HIF-1α) was tested by real-time quantitative PCR and western blotting. At 2 weeks after addition of cardiomyocyte differentiation inducer 5-azacytidine, cardiac troponin T (cTnT) expression was detected by immunofluorescence. After 24 h, the proliferation of the hypoxic group was considerably greater compared with the normoxic group (n = 12,P < 0 05). SEM demonstrated that the number of viable cells in the hypoxic group was higher than that in the normoxic group. Adhesion between cells and the patch was firm and cell morphology was normal in the hypoxic group. Significant upregulation of HIF-1α mRNA was observed by real-time quantitative PCR after 12 h (P < 0 05). HIF-1αprotein expression in the hypoxia group was considerably higher than that in the normoxia group. cTnT expression in the hypoxic group was more pronounced than that in the normoxic group. Our results show that a hypoxic microenvironment promotes the adhesion, survival, proliferation, and myocardial differentiation of bone marrow mesenchymal stem cells on a P(3HB-co-4HB) patch, which may be mediated by the HIF-1α; pathway.

目的:总结主动脉瓣环扩大联合环上型生物瓣膜替换策略,治疗老年小瓣环主动脉瓣狭窄的近中期结果,探讨老年小瓣环主动脉瓣狭窄的治疗策略.方法:2010年1月至2017年1月,28例老年小瓣环主动脉瓣狭窄患者应用主动脉瓣环扩大联合环上型生物瓣替换策略进行治疗,主动脉瓣关闭不全或多个瓣膜病变等排除在本研究之外.男性8例,女性20例,年龄65～ 77岁,平均(70.5±3.48)岁,体表面积1.55～ 1.72 m2,平均(1.63±0.05) m2.按病因分类,退行性主动脉瓣狭窄17例,先天性二叶畸形6例,风湿性改变4例,其他病变1例.患者术前心功能分级(NYHA分级):Ⅱ级6例,Ⅲ级20例,Ⅳ级2例.同时合并疾病包括冠心病5例,2型糖尿病8例,高血压病7例,慢性肾功能不全5例,慢性阻塞性肺疾病3例,心房颤动7例,既往卒中史6例.手术前超声心动图测主动脉瓣环径(17.5±1.02) mm,平均跨瓣压差(59.8± 10.2)mmHg(1 mmHg=0.133 kPa).结果:体外循环时间(105.O±18.8)min,心肌血运阻断时间(71.0±17.1)min.实测主动脉瓣环径(18.1±0.87)mm,应用Nick法扩环25例,Nu(n)ez法3例,扩环后主动脉瓣环径(22.2±0.93) mm,平均增加(4.13±0.78)mm,平均替换瓣膜尺寸(21.8±0.99)mm,预期有效瓣口面积指数(1.10±0.07) cm2/ m2.同期行冠状动脉旁路移植术5例,心房颤动射频消融术7例,左心耳切除术7例.围手术期死亡1例(3.6％),死因为低心排血量综合征.开胸止血术1例,急性肾衰竭1例,肺部感染2例,切口并发症1例,临时起搏治疗6例.出院时平均跨瓣压差(13.14±2.14)mmHg,超声实测有效瓣口面积指数(1.12±0.07) cm2/m2,仅1例发生轻度患者-人造瓣膜不匹配.手术后2年,常规超声心动图检查及临床评估.24例患者心功能Ⅰ级,3例Ⅱ级.患者平均跨瓣压差及左心室质量指数较术前明显改善[(59.8±10.18)vs.(13.8±1.93) mmHg,P＜0.01;(151.3±9.95)vs.(110.6±6.95)g/m2,P＜0.01].5例患者主动脉瓣听诊区可闻及2/6级收缩期杂音,19例患者左心室肥厚得到逆转,8例患者仍存在轻度左心室肥厚.随访时平均有效瓣口面积指数(1.09±0.09) cm2/m2,1例发生轻度患者-人造瓣膜不匹配.结论:主动脉瓣环扩大联合环上型生物瓣替换策略治疗老年小瓣环主动脉瓣狭窄近中期疗效良好,既有效避免患者-人造瓣膜不匹配现象,又避免了长期抗凝所致的血栓栓塞及出血风险.

目的 探究低氧微环境对小鼠骨髓间充质干细胞(mouse bone marrow mesenchymal stem cells,mMSCs)与聚3羟基丁酸酯-co-4羟基丁酸酯[3-hydroxybutyrate-co-4-hydroxybutyrate,P(3HB-co-4HB)]材料共培养形成心肌补片的影响,为细胞移植术治疗心肌梗死提供一种更有效的心肌补片.方法 全骨髓培养法提取小鼠骨髓间充质干细胞(mMSCs),取5代mMSCs流式细胞术鉴定表面抗原.将P(3HB-co-4HB)与小鼠骨髓间充质干细胞共培养制作成细胞补片,随机分为常氧组和低氧组,每组各10个样本,0、12、24 h分别用CCK-8法测定细胞增殖情况;扫描电子显微镜(scanning electron microscope,SEM)观察补片存活、黏附、生长情况.加入诱导剂5-氮杂胞苷2周后,免疫荧光检测两组心肌肌钙蛋白T(cTnT)的表达情况.结果 在共培养24 h后,CCK-8法测定低氧组OD值(0.349±0.038)显著大于常氧组(0.308±0.025)(n=10,P<0.05),扫描电子显微镜观察到低氧组P(3HB-co-4HB)材料上细胞数量更多,细胞与材料之间的黏附牢固,细胞形态正常.免疫荧光显示低氧组cTnT表达比常氧组更加显著.结论 相对于常氧条件,低氧微环境可促进骨髓间充质干细胞在P(3HB-co-4HB)材料上的黏附、存活、增殖、分化,形成一种更有效的心肌补片.

Objective: To investigate the indication and midterm outcomes of surgical treatment of traumatic tricuspid insufficiency. Methods: Totally 19 patients with traumatic tricuspid insufficiency who underwent surgical treatment at Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University from January 2002 to January 2018 were included in this retrospective study. There were 12 male and 7 female patients, aged (43.1±12.9) years (range: 17-68 years). The main causes of traumatic tricuspid insufficiency included blunt chest trauma following high-speed vehicle accidents (17 patients) and high-fall trauma (2 patients). The preoperative New York Heart Association functional class was class Ⅱ in 5 patients, class Ⅲ in 12 patients, and class Ⅳ in 2 patients. The mechanism of tricuspid insufficiency included anterior chordal rupture in 9 patients, anterior papillary muscle rupture in 3 patients, anterior and posterior chordal or papillary muscle rupture in 4 patients, laceration of leaflet combined with chordal rupture in 2 patients and infection combined with anterior papillary muscle rupture in 1 patient. Anular dilation and enlargement of the right ventricle were observed in all the patients. Paired t test was used to evaluate the echocardiogratic results at preoperation, postoperation and follow-up. Independent sample rank sum test was used to evaluate the intervals between trauma and surgery in tricuspid valve repair group and tricuspid valve replacement group. Results: Tricuspid valve repair was successful in 8 patients, and 11 patients underwent valve replacement. Among the patients who underwent valve replacement, 6 patients received mechanical valve and 5 received bioprosthetic valve. The interval from trauma to surgery of the valve repair group and valve replacement group were 8.5(10.0) months (range: 0.1-13.0 months) and 72.0 (108.0) months (range: 2.0-228.0 months), respectively. Concomitant procedures included debridement in scalp trauma (1 patient), internal fixation of femoral fracture (1 patient). One patient died from liver failure 10 days after operation and the remaining patients survived. Eighteen patients were followed up for (94±50) months, 15 patients were in New York Heart Association functional class Ⅰ and 3 patients in class Ⅱ. One patient received redo-tricuspid valve replacement because of mechanical valve failure at the 11 years of follow-up. Conclusions: The midterm outcomes of surgical treatment of severe traumatic tricuspid insufficiency were satisfactory. Early diagnosis and surgical invention were recommended to achieve successful valve repair.

Objective To observe the surgical outcome and survival of patients with tricuspid valve mechanical prosthesis replacement.Methods Clinical data of 36 patients receiving tricuspid mechanical valve replacement in Beijing Anzhen Hospital,Capital Medical University between January 2010 and December 2017 was retrospectively reviewed.There were 14 females and 22 males,with a mean age of (52 ± 9) years (28-64 years old).Among the patients,22 cases were in New York Heart Association(NYHA) functional class Ⅱ,12 cases were in NYHA class Ⅲ[and 2 cases were in NYHA class Ⅳ.Tricuspid valvular lesion of all patients was confirmed by echocardiography and surgical findings.There were 28 cases of rheumatic heart disease,4 cases of tricuspid valvular hypoplasia,3 cases of congenital heart disease (Ebstein's anomaly) and 1 case of tetralogy of Fallot.Mechanical valve replacement of tricuspid valve or multi-valve replacement was implemented and 45 mechanical prostheses were used.Results Three patients died of right heart insufficiency,infection and multiple organ dysfunction,the postoperative in-hospital mortality was 8.3％ (3/36).One patient was discharged 97 days after surgery;32 patients were discharged in 8-21 days after surgery.The mean follow-up interval was 3-42 months in 33 patients(91.7％).During follow-up,1 patient developed paravalvular leakage 3 months after surgery and underwent reoperation of bioprosthetic valve replacement;other patients survived without any valve-related events.Conclusions Tricuspid valve replacement has high risks of mortality and morbidity and requires rigorous indications.Patients with no indication of tricuspid valve repair or failure in repair can have valve replacement and the surgical effect is valid.

目的:观察乌司他丁对心脏瓣膜病行直视手术的患者术后的细胞因子及左心室功能的影响.方法:选择全身麻醉体外循环心脏瓣膜病60例,纽约心功能分级(New York Heart Association,NYHA)和美国麻醉协会(American Society of Anesthesiology,ASA)分级为Ⅱ～Ⅲ级.采用随机数字法分成两组,各30例.观察组在常规治疗的基础上在心脏停搏液内加入乌司他丁15000 U/kg,常规组无此处理.两组患者分别于麻醉诱导前(T1)、体外循环后10 min(T2)、心脏瓣膜置换术后2 h(T3)及术后24 h(T4)从中心静脉插管采集血标本4次,测定心肌酸激酶同工酶、心肌钙蛋白,血清肿瘤坏死因子α(tumor necrosis factorα,TNF-α)、白细胞介素(interleukin,IL)-6、IL-8及IL-10.观察两组患者的血清细胞因子水平、术后血流动力学稳定情况和术后心功能恢复情况.结果:两组患者经过治疗后症状均明显好转,心功能明显改善.观察组各监测时刻的TNF-α、IL-6及IL-8水平均明显低于常规组(均P<0.05),而IL-10水平均高于常规组(均P<0.05).两组左心室舒张末内径、 左心室射血分数、右心房平均压、平均肺动脉压、体循环阻力比较差异均有统计学意义(均P<0.05).结论:乌司他丁通过调节细胞因子的水平,减轻体外循环后的缺血再灌注损伤,改善左心室功能.