不稳定心绞痛罪犯斑块冠状动脉CT造影与光学相干成像的相关性研究

目的 观察不稳定心绞痛患者的罪犯斑块的冠状动脉CT造影（CTCA）和光学相干成像（OCT）特征的相关性。方法 入选2012年6月~2014年2月在解放军总医院心内科住院并行CTCA、OCT检查的不稳定心绞痛患者，常规获取病史和临床检验指标。分析CTCA显示罪犯病变最小CT值、CT重构指数和OCT显示罪犯斑块最薄纤维帽厚度、内膜撕裂和血栓的关系。依据最薄纤维帽厚度分将患者为≤65μm和＞65μm两组，比较两组患者最小CT值、CT重构指数、内膜撕裂及血栓发生率情况。结果 最薄纤维帽厚度与对应截面最小CT值之间正相关，相关系数r=0.627，P＜0.001；而CT重构指数与最薄纤维帽厚度负相关，相关系数r=-0.45，P=0.006。最薄纤维帽厚度≤65μm和＞65μm两组患者CTCA显示的最小CT值（50.7±25.5 vs. 78.7±29.8，P=0.006）、CT重构指数（1.34±0.22 vs. 1.12±0.15，P=0.0013）、内膜撕裂（78.6% vs. 19%，P=0.001）均有显著统计学差异；血栓发生率有差别（50.0% vs. 14.3%，P=0.053），但未达统计学差异。内膜最薄厚度与CTCA及临床指标逐步回归分析显示内膜厚度与斑块最小CT值、CTRI相关，偏相关系数分别为0.64、-0.28。结论 结合CTCA最小CT值、CTRI对预测内膜撕裂的有帮助。

Transplantation of autologous adipose-derived stem cells ameliorates cardiac function in rabbits with myocardial infarction

Background Adipose-derived stem cells （ADSCs） are capable of differentiating into cardiomyogenic and endothelial cells in vitro. We tested the hypothesis that transplantation of ADSCs into myocardial scar may regenerate infracted myocardium and restore cardiac function. Methods ADSCs were isolated from the fatty tissue of New Zealand white rabbits and cultured in Iscove＇s modified dulbecco＇s medium. Three weeks after ligation of left anterior descending coronary artery of rabbits, either a graft of untreated ADSCs （UASCs, n=14）, 5-azacytidine-pretreated ADSCs （AASCs, n=13）, or phosphate buffer saline （n=13） were injected into the infarct region. Transmural scar size, cardiac function, and immunohistochemistry were performed 5 weeks after cell transplantation. Results ADSCs in culture demonstrated a fibroblast-like appearance and expressed CD29, CD44 and CD105. Five weeks after cell transplantation, transmural scar size in AASC-implanted hearts was smaller than that of the other hearts. Many ADSCs were differentiated into cardiomyocytes. The AASCs in the prescar appeared more myotube-like. AASCs in the middle of the scar and UASCs, in contrast, were poorly differentiated. Some ADSCs were differentiated into endothelial cells and participate in vessel-like structures formation. All the ADSC-implanted hearts had a greater capillary density in the infarct region than did the control hearts. Statistical analyses revealed significant improvement in left ventricular ejection fraction, myocardial performance index, end-diastolic pressure, and peak ＋dP/dt, in two groups of ADSC-implanted hearts relative to the control hearts. AASC-implanted hearts had higher peak -dP/dt values than did control, higher ejection fraction and peak ＋dP/dt values than did UASC-implanted hearts. Conclusions ADSCs transplanted into the myocardial scar tissue formed cardiac islands and vessel-like structures, induced angiogenesis and improved cardiac function. 5-Azacytidine pretreatment before implantation is desirable for augmenting myogenesis. Transplantation of 5-azacytidine-treated ADSCs into the myocardial scar was more efficient than that of untreated ADSCs in preservation of cardiac function.

Four-year clinical outcome in asymptomatic patients undergoing coronary computed tomography angiography

Background Percutaneous coronary intervention （PCI） is indicated for angina with coronary stenosis. However, PCI for asymptomatic coronary stenosis remains controversial. We prospectively followed a group of patients for four years who underwent coronary computed tomography angiography （CCTA） for major adverse cardiac events （MACE）. We hypothesized that the results of this trial would reliably reflect the natural outcome of the coronary disease. Methods Consecutive patients who underwent CCTA from June 2008 to May 2009 were selected. Those who could not be reached by telephone, had significant angina, had CT images that were not interpretable, or poor kidney and left ventricular （LV） function were excluded. The patients were divided into five groups： group A normal CCTA without stenosis, group B mild stenosis （1%-49%）, group C moderate stenosis （50%-74%）, group D severe stenosis （≥75%） and they were treated with optimal medical therapy （OMT） or PCI. The group E had PCI before the CCTA examination. The patients were then followed for MACE after different treatments. MACE included acute myocardial infarction （MI）, heart failure （HF） and death. Results The patient population consisted of 419 patients. The follow-up time was （51±5） months. The age was （60±31） years. Male made up 67.78% of the population （n=284）. A total of 51 cases of MACE occurred including 25 MI, eight HF and 18 all-cause deaths. There was no MACE in group A. Although MACE occurred in two patients in group B, they were not attributed to cardiac death. We further compared the MACE in groups C-E and no significant difference was found （P 〉0.05）. However, a difference was detected among patients with unstable angina pectods （UAP）, stable angina pectoris （SAP）, re-hospitalization, and cerebrovascular events from groups A-E （P 〈0.05）. The plaque scores were used to predict MACE. The scores progressively increased significantly with lesion severity （P 〈0.05）. Receiver operating curve （ROC） was performed to determine the sensitivity and specificity in predicting MACE. Our scores predicted MI with area of 0.76, predicted HF with area of 0.77, and predicted death with area of 0.70. Conclusions Normal and mild lesions had very few events. With increased stenosis the MACE rate increased progressively. PCI did not significantly reduce the MACE in comparison with OMT in asymptomatic patients. Furthermore, UAP, re-hospitalization, and re-PCI were sianificantlv increased in patients who were treated with PCI.

Optical coherence tomography assessment of edge dissections after drug-eluting stent implantation in coronary artery

Background Edge dissections after coronary stent implantation are associated with increased short-term risk of major adverse cardiovascular events. The incidence and outcome of edge dissections after coronary stent implantation were reportedly different using different imaging techniques. We used optical coherence tomography （OCT） to assess the incidence, morphological findings and related factors of edge dissections after drug-eluting stent （DES） implantation. Methods Totally 42 patients with 43 de novo lesions in 43 native arteries undergoing DES implantation with OCT imaging were enrolled in this study. Results Nine edge dissections were detected in 43 arteries after DES implantation. There were four morphological patterns of stent edge dissections indentified in this study： （1） superficial intimal tears （n=3）, （2） subintimal dissections （n=4）, （3） split of media （n=1）, （4） disruption of the fibrotic cap of plaque （n=1）. Stent edge expansion and stent expansion were both higher in the group with dissections than those in the group without dissections （1.682±0.425 vs. 1.229±0.285, P=0.0290; 1.507±0.445 vs. 1.174±0.265, P=0.0072）. Conclusions The incidence of stent edge dissections detected by OCT was 21%. Stent edge dissection is related with stent edge expansion and stent expansion.