Objectives The long-term benefit of late reperfusion of infarct-related artery （IRA） after acute myocardial infarction （AMI） is controversial, and the benefit mechanisms remain uncertain. Low dose dobutamine stres...Objectives The long-term benefit of late reperfusion of infarct-related artery （IRA） after acute myocardial infarction （AMI） is controversial, and the benefit mechanisms remain uncertain. Low dose dobutamine stress echocardiography （LDSE） can identify viable myocardium and predict improvement of wall motion after revascularization. Methods Sixtynine patients with first AMI who did not received early reperfusion therapy were studied by LDSE at 5 to 10 days after AMI. Wall motion abnormality and left ventricular size were measured at the same time. Successful PCI were done in all patients at 10 to 21 days after AMI onset. Patients were divided in two groups based on the presence or absence of viable myocardium. Echocardiography was repeated six months later. Results There were 157 motion abnormality segments. 89 segments （57%） were viable during LDSE. 26 patients （38%） with viability and 43 （62%） without. In viable group, left ventricular ejection fraction （LVEF） was increased （P 〈 0.05）, and left ventricular end systolic volume index （LVESVI） and wall motion score （WMS） were decreased （P 〈 0.05 and P 〈 0.01） significantly at 6 months compared with baseline. But in patients without viability, LVEF was decreased （P 〈 0.01）, and LVESVI and left ventricular end diastolic volume index （LVEDVI） were increased （P 〈 0.05） significantly after 6 months, and the WMS did not changed （P 〉 0.05 ）. LVEF increased （P 〈 0.05 ） and WMS decreased （P 〈 0.05） on LDSE during acute phase in patients with viability, but they were not changed in the nonviable group. Conclusions Late revascularization of IRA in patients with presence of viable myocardium after AMI is associated with long-term preservation left ventricular function and less ventricular remodeling. Improvement of left ventricular systolic function on LDSE indicates late phase recovery of left ventricular function after late revascularization.展开更多
One hundred and fifty Wistar rats were randomized into a control group with shamoperation and a left coronary artery occlusion group.Specimens of the blood and myocardiumwere collected at different intervals m 2 month...One hundred and fifty Wistar rats were randomized into a control group with shamoperation and a left coronary artery occlusion group.Specimens of the blood and myocardiumwere collected at different intervals m 2 months after operation.The morphological changes ofthe myocardium were observed trader optical and electron microscope.Malondialdehyde(MDA)level of the serum and myocardial homogenate,and the activities of lactic dehydrogenase(LDH),succinic dehydrogenase(SDH)and ATPase and histochemical changes of calcium in the ischemicmyocardium were studied.It was found that the mafia changes of myocardial infarction weremyocardial necrosis in the early stage and repair in the late stage.The ultrastructural changes ofischemic injury appeared quite early and involved ahnost all the subcellular organelles.The repairin the late stage was mainly incomplete regeneration of a few myoo.trdM cells.The significanceof the“junction-like”structure of fibroblasts was not dean,it was probably one of themorphological basis of scars.The activities of the enzymes were quickly suppressed afterocclusion,which suggests the exhaustion of energy metabolism.The MDA level of the myocardialhomogenate elevated in the first 24 h after occlusion,suggesting that myocardial ischemia can in-crease lipid peroxidation reduced by oxygen free radicals,It might be one of the Factors of theirreversibility of ischemic myocardial damage.展开更多
The theraputic effectiveness of primary coronary stenting was evaluated and compared with that of intravenous thrombolysis for acute myocardial infarction (AMI) using99m Tc-MIBI myocardial SPECT imaging. 42 patients w...The theraputic effectiveness of primary coronary stenting was evaluated and compared with that of intravenous thrombolysis for acute myocardial infarction (AMI) using99m Tc-MIBI myocardial SPECT imaging. 42 patients with AMI were undergone primary coronary stenting (stenting group, 23 patients) or intravenous thrombolysis therapy (thrombolysis group, 19 patients). 99mTc-MIBI myocardium SPECT imaging was performed before and 1 week after steming or thrombolysis therapy. The left ventricular myocardium of each patient was divided into 20 segments. The semiquantitative score of myocardial 99mTc-MIBI uptake was eXPressed with a five-point scoring system: 0 = normal; 1 = equivocal; 2 = mild defect; 3 = severe defect; 4 = absence of activity. The scores of scanning before stenting or intravenous throm-bolysis was SBS. The scores of scaning after stenting or intravenous thrombolysis was SAS. Deducting SAS from SBS was SDS. A comparison was made between the steming group and thrombolysis group: SBS was 41.3+9.8 and 39.4+7.9 (t=1.2, p <0.05); SAS was 17.8+6.4 and 27.3+6.7 (t=5.8, p <0.01); SDS was 24.5+4.2 and 12.2+2.3 (t = 7.3, P <0.01). In the 193 defect segments before stenting, 106 segments (54.9%) restored to normal after steming. In the 149 defect segments before intravenous thrombolysis, 61 segments (40.9%) restored to normal after thrombolysis therapy. Comparing between steming group and thrombolysis group in the improved rate of myocardial perfusion defect scores there was a significant difference (p <0.01). 99mTc-MIBI myocardial SPECT imaging has been proved to be an objective parameter for evaluating the therapeutic effectiveness of the stenting and the intravenous thrombolysis in the treatment of AMI. The results indicated that primary coronary stenting seems to be more effective than intravenous thrombolysis.展开更多
文摘Objectives The long-term benefit of late reperfusion of infarct-related artery （IRA） after acute myocardial infarction （AMI） is controversial, and the benefit mechanisms remain uncertain. Low dose dobutamine stress echocardiography （LDSE） can identify viable myocardium and predict improvement of wall motion after revascularization. Methods Sixtynine patients with first AMI who did not received early reperfusion therapy were studied by LDSE at 5 to 10 days after AMI. Wall motion abnormality and left ventricular size were measured at the same time. Successful PCI were done in all patients at 10 to 21 days after AMI onset. Patients were divided in two groups based on the presence or absence of viable myocardium. Echocardiography was repeated six months later. Results There were 157 motion abnormality segments. 89 segments （57%） were viable during LDSE. 26 patients （38%） with viability and 43 （62%） without. In viable group, left ventricular ejection fraction （LVEF） was increased （P 〈 0.05）, and left ventricular end systolic volume index （LVESVI） and wall motion score （WMS） were decreased （P 〈 0.05 and P 〈 0.01） significantly at 6 months compared with baseline. But in patients without viability, LVEF was decreased （P 〈 0.01）, and LVESVI and left ventricular end diastolic volume index （LVEDVI） were increased （P 〈 0.05） significantly after 6 months, and the WMS did not changed （P 〉 0.05 ）. LVEF increased （P 〈 0.05 ） and WMS decreased （P 〈 0.05） on LDSE during acute phase in patients with viability, but they were not changed in the nonviable group. Conclusions Late revascularization of IRA in patients with presence of viable myocardium after AMI is associated with long-term preservation left ventricular function and less ventricular remodeling. Improvement of left ventricular systolic function on LDSE indicates late phase recovery of left ventricular function after late revascularization.
文摘One hundred and fifty Wistar rats were randomized into a control group with shamoperation and a left coronary artery occlusion group.Specimens of the blood and myocardiumwere collected at different intervals m 2 months after operation.The morphological changes ofthe myocardium were observed trader optical and electron microscope.Malondialdehyde(MDA)level of the serum and myocardial homogenate,and the activities of lactic dehydrogenase(LDH),succinic dehydrogenase(SDH)and ATPase and histochemical changes of calcium in the ischemicmyocardium were studied.It was found that the mafia changes of myocardial infarction weremyocardial necrosis in the early stage and repair in the late stage.The ultrastructural changes ofischemic injury appeared quite early and involved ahnost all the subcellular organelles.The repairin the late stage was mainly incomplete regeneration of a few myoo.trdM cells.The significanceof the“junction-like”structure of fibroblasts was not dean,it was probably one of themorphological basis of scars.The activities of the enzymes were quickly suppressed afterocclusion,which suggests the exhaustion of energy metabolism.The MDA level of the myocardialhomogenate elevated in the first 24 h after occlusion,suggesting that myocardial ischemia can in-crease lipid peroxidation reduced by oxygen free radicals,It might be one of the Factors of theirreversibility of ischemic myocardial damage.
文摘The theraputic effectiveness of primary coronary stenting was evaluated and compared with that of intravenous thrombolysis for acute myocardial infarction (AMI) using99m Tc-MIBI myocardial SPECT imaging. 42 patients with AMI were undergone primary coronary stenting (stenting group, 23 patients) or intravenous thrombolysis therapy (thrombolysis group, 19 patients). 99mTc-MIBI myocardium SPECT imaging was performed before and 1 week after steming or thrombolysis therapy. The left ventricular myocardium of each patient was divided into 20 segments. The semiquantitative score of myocardial 99mTc-MIBI uptake was eXPressed with a five-point scoring system: 0 = normal; 1 = equivocal; 2 = mild defect; 3 = severe defect; 4 = absence of activity. The scores of scanning before stenting or intravenous throm-bolysis was SBS. The scores of scaning after stenting or intravenous thrombolysis was SAS. Deducting SAS from SBS was SDS. A comparison was made between the steming group and thrombolysis group: SBS was 41.3+9.8 and 39.4+7.9 (t=1.2, p <0.05); SAS was 17.8+6.4 and 27.3+6.7 (t=5.8, p <0.01); SDS was 24.5+4.2 and 12.2+2.3 (t = 7.3, P <0.01). In the 193 defect segments before stenting, 106 segments (54.9%) restored to normal after steming. In the 149 defect segments before intravenous thrombolysis, 61 segments (40.9%) restored to normal after thrombolysis therapy. Comparing between steming group and thrombolysis group in the improved rate of myocardial perfusion defect scores there was a significant difference (p <0.01). 99mTc-MIBI myocardial SPECT imaging has been proved to be an objective parameter for evaluating the therapeutic effectiveness of the stenting and the intravenous thrombolysis in the treatment of AMI. The results indicated that primary coronary stenting seems to be more effective than intravenous thrombolysis.
文摘目的探讨ST段抬高型心肌梗死(STEMI)患者,直接经皮冠状动脉介入治疗(pPCI)术后48 h内心肌血流灌注延迟时间(MFPDT)的临床价值。方法选取并分析71例已行pPCI治疗STEMI患者的临床资料,术后48 h行左心室超声造影检查,分析MFPDT与节段心肌功能(RMF)、左心室射血分数(LVEF)的相关性;依据RMF分为轻度组和严重组,比较两组间MFPDT及LVEF差异及术后平均8.5个月房室大小、LVEF、室壁瘤发生率。正态分布计量资料行t检验,计数资料行χ^(2)检验。采用多因素Logistic回归模型分析室壁瘤形成的影响因素,P<0.05为差异有统计学意义。结果术后48 hMFPDT与RMF呈正相关(r=0.5420,P<0.0001),术后48 h MFPDT与LVEF呈弱相关,与末次随访时LVEF不相关(r分别为-0.2869、-0.1950,P分别为0.0153、0.1034)。心肌受损轻度组31例,室壁瘤4例,严重组40例,室壁瘤18例,两组术后48 h MFPDT及术后室壁瘤发生率比较差异有统计学意义(χ^(2)=19.0280、8.4100,P=0.0003、0.0037),LVEF差异无统计学意义(P>0.05),术后末次随访时两组间房室大小差异无统计学意义(P>0.05)。多因素Logistic回归分析发现,MFPDT是STEMI患者短期预后的主要影响因素(OR=3.0460,P<0.0001,95%CI:1.750~5.301)。结论STEMI患者pPCI术后48 h内MFPDT可初步预测患者心肌损伤严重程度。
