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1.
Myocardial hibernation refers to a state of prolonged impairment of left ventricular function in the presence of coronary artery disease, which may be reversed by revascularization. In this study we present evidence for a local inflammatory reaction in hibernating myocardial segments from patients undergoing coronary revascularization. We obtained transmural myocardial biopsies guided by transesophageal echocardiography from patients with ischemic ventricular dysfunction undergoing bypass surgery. Among the 28 biopsied segments included in the study, 23 showed evidence of systolic dysfunction. The majority of dysfunctional segments (85.7%) were viable ((201)Tl uptake >/= 60%). The samples were stained with markers for mast cells, mature resident macrophages, and the monoclonal antibody Mac387 that labels newly recruited myeloid cells. Dysfunctional segments showed more extensive fibrosis and higher macrophage density than normal segments. Among the 23 dysfunctional segments, 12 recovered function as assessed with echocardiograms 3 months after revascularization. Segments with postoperative functional recovery had comparable macrophage and mast cell density with those showing persistent dysfunction. However, biopsied segments that subsequently recovered function contained significantly higher numbers of newly recruited Mac387-positive leukocytes (18.7 +/- 3.1 cells/mm(2), n = 12 versus 8.6 +/- 0.9 cells/mm(2), n = 11; P = 0.009). In addition, monocyte chemotactic protein-1, a potent mononuclear cell chemoattractant, was predominantly expressed in segments with recovery of function. Myocardial hibernation is associated with an inflammatory response leading to active leukocyte recruitment. Dysfunctional myocardial segments that show an active inflammatory reaction have a greater potential for recovery of function after revascularization. We postulate that revascularization may promote resolution of the ongoing inflammation, preventing further tissue injury and fibrosis.  相似文献   

2.
Results of 145 surgeries for direct myocardial revascularization without artificial circulation are presented. FC III and IV angina of effort was diagnosed in 80.6% and 13.5% of the patients respectively, acute coronary syndrome in 6.5%, past myocardial infarction in 63.8%. Mean left ventricular ejection fraction (EF) prior to surgery was 48.7 +/- 5.1%; it was below 40% in 28.8% of the patients. Three- and two-vessel coronary disease was documented in 54.7% and 35.3% of the patients respectively; 10% of them presented with the affected anterior interventricular branch, 14% with the stenotic trunk of the left coronary artery. Mean revascularization index increased from 22 to 76. The frequency of complete autoarterial revascularization amounted to 42.7%. Sequential and composite grafts were used in 93 and 257 cases respectively. No patient experienced perioperative myocardial infarction, acute disturbance of cerebral circulation, acute renal or cardiac insufficiency. Immediate postoperative hemorrhage requiring resternotomy developed in 0.9% of the patients, 1.2% with suppurative complications needed additional surgical treatment. It is concluded that myocardial revascularization on a beating heart is an efficacious and reliable method ensuring good results in the immediate and late postoperative period. Its success first and foremost depends on the previously gained experience that permits to operate patients with severe multi-vessel coronary artery disease and various concomitant disorders and thereby correct combined pathological conditions. The available data give reason to consider each patients in need of aortocoronary bypass as a candidate for myocardial revascularization on a beating heart regardless of the character and extent of coronary lesions and anatomical feature of the coronary bed.  相似文献   

3.
BACKGROUND: Recent studies indicate that magnetic resonance imaging (MRI) after the administration of contrast material can be used to distinguish between reversible and irreversible myocardial ischemic injury regardless of the extent of wall motion or the age of the infarct. We hypothesized that the results of contrast-enhanced MRI can be used to predict whether regions of abnormal ventricular contraction will improve after revascularization in patients with coronary artery disease. METHODS: Gadolinium-enhanced MRI was performed in 50 patients with ventricular dysfunction before they underwent surgical or percutaneous revascularization. The transmural extent of hyperenhanced regions was postulated to represent the transmural extent of nonviable myocardium. The extent of regional contractility at the same locations was determined by cine MRI before and after revascularization in 41 patients. RESULTS: Contrast-enhanced MRI showed hyperenhancement of myocardial tissue in 40 of 50 patients before revascularization. In all patients with hyperenhancement the difference in image intensity between hyperenhanced regions and regions without hyperenhancement was more than 6 SD. Before revascularization, 804 of the 2093 myocardial segments analyzed (38 percent) had abnormal contractility, and 694 segments (33 percent) had some areas of hyperenhancement. In an analysis of all 804 dysfunctional segments, the likelihood of improvement in regional contractility after revascularization decreased progressively as the transmural extent of hyperenhancement before revascularization increased (P<0.001). For instance, contractility increased in 256 of 329 segments (78 percent) with no hyperenhancement before revascularization, but in only 1 of 58 segments with hyperenhancement of more than 75 percent of tissue. The percentage of the left ventricle that was both dysfunctional and not hyperenhanced before revascularization was strongly related to the degree of improvement in the global mean wall-motion score (P<0.001) and the ejection fraction (P<0.001) after revascularization. CONCLUSIONS: Reversible myocardial dysfunction can be identified by contrast-enhanced MRI before coronary revascularization.  相似文献   

4.
目的 分析早期检测血清白蛋白(albumin,ALB)对急性心肌梗死患者急性肾损伤的预测价值。方法 纳入急性心肌梗死患者100例,其中有急性肾损伤患者48例,无急性肾损伤患者48例,探讨早期血清ALB对急性心肌梗死患者发生急性肾损伤的预测价值。结果 两组患者在性别、年龄和体质量指数上无统计学差异(P>0.05);有急性肾损伤患者的心率、收缩压、舒张压、尿量、白细胞、血糖、血肌酐水平更高,行冠状动脉支架治疗概率、左室射血分数、红细胞比容、ALB水平更低(P<0.05);多因素Logistic回归分析显示,肾损伤的危险因素包括ALB、白细胞计数和血肌酐(P<0.05);经校正混杂因素后,低ALB血症为肾损伤的危险因素(P<0.05)。结论 早期检测血清ALB水平,可对急性心肌梗死患者发生急性肾损伤的风险进行预测。  相似文献   

5.
目的:比较急性心肌梗死(AMI)患者行冠脉介入术(PCI)前后血清中缺血修饰白蛋白(IMA)水平的变化,探讨IMA的形成机制及其对心肌缺血早期诊断和疗效观察的临床意义。方法:采用白蛋白钴结合(ACB)试验分别测定对照组和AMI患者PCI前及PCI后不同时间段血清IMA水平。结果:心肌缺血引起血清IMA急性升高(P<0.05),术后3h回复到术前水平,术后6h~30h血清IMA与术前比较显著降低(P<0.05)。结论:心肌缺血可造成AMI患者血中IMA急性升高;PCI可有效改善心肌缺血状况。IMA可作为心肌缺血早期诊断和疗效观察的重要指标。  相似文献   

6.
目的 探讨急性心肌梗死(AMI)冠脉严重程度与骨桥蛋白(OPN)的相关性。方法 回顾性分析2016年9月~2017年12月我院收治的急性心肌梗死患者127例,根据OPN水平分为高OPN组65例和低OPN组62例,比较两组患者基础资料及多元线性分析OPN与冠脉严重程度的影响因素。结果 两组年龄、TG、TC、HDL-C、LDL-C及Gensini积分比较,差异有统计学意义(P<0.05);两组性别、既往史、左室射血分数、药物治疗比较,差异无统计学意义(P>0.05)。多元线性回归结果表明,OPN、年龄、LDL-C和HDL-C为Genisi积分的独立影响因素。结论 OPN与AMI患者冠脉病变严重程度独立相关,可评估急性心肌梗死冠脉病变严重程度。  相似文献   

7.
Acute myocardial infarction (AMI) is rare in patients with idiopathic thrombocytopenic purpura (ITP). We describe a case of an AMI during thrombocytopenia in a patient with chronic ITP. A 47-yr-old woman presented with anterior chest pain and a low platelet count (21,000/microliter) at admission. Urgent coronary angiography revealed total occlusion of proximal right coronary artery and primary percutaneous coronary intervention (PCI) was performed successfully. This case suggests that primary PCI may be a therapeutic option for an AMI in patients with ITP, even though the patient had severe thrombocytopenia.  相似文献   

8.
目的:探讨急性心肌梗死(AMI)患者经皮冠状动脉介入治疗(PCI)前后血清可溶性CD40L的水平变化及临床意义.方法:应用酶联免疫吸附法对40例AMI患者进行了PCI治疗前后血清sCD40L、cTnI及CK-MB的检测,并与40例对照组患者进行比较.结果:AMI组sCD40L水平在PCI术前及术后即刻及术后2h均高于对...  相似文献   

9.
Aims: Strain rate imaging techniques have been proposed for the detection of ischemic or viable myocardium in coronary artery disease, which is still a challenge in clinical cardiology. This retrospective comparative study analyzed regional left ventricular function and scaring with two-dimensional strain (2DS) in the first 4 to 10 days after acute anterior myocardial infarction (AMI).Methods and results: The study population consisted of 32 AMI patients with an LAD occlusion and successful reperfusion. The assessment of peak systolic 2DS and peak systolic strain rate (SR) was performed segment-oriented with the angle-independent speckle tracking algorithm Velocity Vector Imaging (VVI). The infarcted, adjacent and non-infarcted segments were revealed by late enhancement MRI (LE-MRI), which was used as reference for the comparison with 2DS. The infarcted segments showed a significant decrease of tissue velocities, 2DS and SR in comparison to the non-affected segments.Conclusion: 2DS and SR as assessed by VVI seem to be a suitable approach for echocardiographic quantification of global and regional myocardial function as well as a promising tool for multimodal risk stratification after anterior AMI.  相似文献   

10.
Reperfusion therapy in acute ST-elevation myocardial infarction includes thrombolytic therapy and primary percutaneous transluminal coronary angioplasty (pPTCA) or primary coronary intervention (pPCI). Many clinical trials have been done to compare the efficacy of treatment of patients with acute myocardial infarction with thrombolytic therapy vs. primary coronary angioplasty. A meta-analysis of 23 randomized trials including 7739 patients with acute myocardial infarction (AMI) showed better results with pPCI in reducing overall short-term death (7% vs. 9%, p = 0.0002), non-fatal reinfarction (2.5% vs. 6.8%, p < 0.0001), death excluding cardiogenic shock (5% vs. 7, p = 0.0003) and combined endpoint of death, non-fatal reinfarction and stroke (8% vs. 14%, p < 0.0001). Primary PCI was better than thrombolytic therapy irrespective of the type of thrombolytic agent used even then when reperfusion was delayed because of patient transfer to a corresponding teriary center for primary PCI. Primary PCI is more effective than thrombolytic therapy for the treatment of ST-segment elevation AMI.  相似文献   

11.
Up to 10% of patients who arrive at the hospital with acute myocardial infarction (AMI) present with or develop cardiogenic shock. Some patients, despite inotropes and intra-aortic balloon pump (IABP) placement, are not hemodynamically stable enough to undergo emergent revascularization. The use of percutaneous extracorporeal life support (ECLS) can stabilize patients to allow effective therapy. In a retrospective review of the first 100 patients emergently placed on ECLS by a nurse-supported physician insertion technique at Sharp Memorial Hospital, 10 patients underwent placement of ECLS after out-of hospital AMI. All AMI patients required intubation for respiratory failure and temporary CPR for cardiovascular collapse before initiation of ECLS. Of the 10 AMI patients placed on ECLS, four (40%) are currently long-term survivors (5.1 +/- 4.2 years; range, 6 months to 11 years). All survivors underwent successful revascularization after placement on ECLS. The cause of death in the other six patients was neurologic insufficiency in two, ineffective ECLS in two, and recurrent cardiovascular collapse after weaning from bypass in two. Total CPR time before initiation of cardiopulmonary bypass was 17 +/- 10.3 minutes for the survivors and 54.2 +/-11.1 minutes for the nonsurvivors (p < 0.001). The average time on ECLS was 29 +/- 26 hours for the survivors and 30 +/-67 hours for the nonsurvivors (p = NS). Leg complications were common among long-term survivors, associated with the use of ECLS (three ischemia, one infection). After AMI and cardiovascular collapse, insertion of ECLS may permit long-term patient survival.  相似文献   

12.
One year's experience of an acute revascularization program for unstable angina pectoris is presented. In the total material of 63 patients, significant coronary artery stenosis was found in 61 and normal coronary arteries in two. Coronary artery bypass grafting was performed in 39 patients (62%) and percutaneous transluminal angioplasty in nine (14%). There were two perioperative myocardial infarctions and one hospital death. Thirteen patients were not eligible for revascularization. At follow-up (14-26 months) 60 patients were still alive (95%). In the revascularization group, one patient had died, but of the remaining 46 patients, 30 (65%) were free of angina pectoris, and in addition six had only minor symptoms.  相似文献   

13.
For patients with coronary artery disease and left ventricular dysfunction who undergo revascularization, it is important to estimate the left ventricular ejection fraction (LVEF) improvement after revascularization, as this is a strong indicator of the long-term outcome. Identification of viable segments from echocardiography has been considered a predictive sign of LVEF improvement. However, a quantitative relation between segmental function recovery and global ejection fraction improvement has not been established. There is a clinical need to determine parameters that are predictive to LVEF improvement. A cylindrical left ventricular model is proposed to establish the relation between segmental myocardial function and LVEF based on a 12-segment echocardiograph model. Model results show that LVEF improvement is directly related to the contraction ratio in normal segments and a weighted sum of the number of viable segments that recover to normal or hypokinetic, which is equal to a weighted sum of the change in wall motion scores. This new combined parameter is a better predictor of the amount of LVEF improvement than the total number of viable segments or preoperative ejection fraction. The predictive value of the model was illustrated in a group of four patients with coronary artery disease who underwent revascularization.  相似文献   

14.
目的观察愈心梗液保护大鼠急性心肌梗死(AMI)后状动脉造成实验性AMI心力衰竭模型,并使之长期存活。造模成心力衰竭心肌细胞及线粒体超微结构和抗氧化的作用。方法结扎Wistar大鼠冠功后,大鼠随机分为7组,每组10只,即空白组、假手术(只穿刺不结扎)组、模型组、开搏通组、愈心梗液大、中、小剂量组。各给药组于手术即日起开始灌胃给药,连续4周。4周后麻醉处死大鼠.心脏组织切片处理后通过电镜和光镜观察心肌细胞及线粒体的形态结构及测定心肌细胞的横截面积、周长,同时测定大鼠心肌组织和血清中丙二醛(MDA)和超氧化物歧化酶(SOD)的含量。结果动物造模4周后,大鼠心肌细胞中心肌纤维排列杂乱,图像系统测量显示心肌细胞横截面积增大、周长增加。与模型组比较,愈心梗液大、中剂量可显著降低大鼠心肌细胞横截面积、周长和直径(和模型比较,P〈0.01)。减少大鼠心肌组织和血清中MDA的含量和升高SOD的含量。结论愈心梗液可抑制大鼠AMI后心肌细胞的代偿性增大,保护线粒体结构的相对完整性,提高大鼠的抗氧化能力,干预AMI大鼠心室重构VR的病理过程,有改善AMI后心力衰竭的作用。  相似文献   

15.
Percutaneous transluminal coronary angioplasty (PTCA) is now capable of providing myocardial revascularization in a majority of patients, but significant problems with the technique remain. It is unsuitable for dealing with diffuse coronary artery disease, chronically occluded vessels may be impossible to disobliterate, and disease of the distal coronary vessel may be difficult to reach with a balloon. Approximately 5 percent of all procedures may be complicated by acute occlusion of the target vessel, usually by dissection of the arterial intima, often resulting in a need for emergency coronary artery bypass surgery (CABG). Furthermore, there is recurrence of the dilated lesion--'restenosis'--in approximately 30 percent of cases in the first 3 to 6 months after PTCA. Advances in this technique, since its introduction in the mid 1970s, have been directed at making initial success more likely, obviating the need for emergency CABG, and reducing the incidence of restenosis.  相似文献   

16.
For patients with coronary artery disease and left ventricular dysfunction who undergo revascularization, it is important to estimate the left ventricular ejection fraction (LVEF) improvement after revascularization, as this is a strong indicator of the long-term outcome. Identification of viable segments from echocardiography has been considered a predictive sign of LVEF improvement. However, a quantitative relation between segmental function recovery and global ejection fraction improvement has not been established. There is a clinical need to determine parameters that are predictive to LVEF improvement. A cylindrical left ventricular model is proposed to establish the relation between segmental myocardial function and LVEF based on a 12-segment echocardiograph model. Model results show that LVEF improvement is directly related to the contraction ratio in normal segments and a weighted sum of the number of viable segments that recover to normal or hypokinetic, which is equal to a weighted sum of the change in wall motion scores. This new combined parameter is a better predictor of the amount of LVEF improvement than the total number of viable segments or preoperative ejection fraction. The predictive value of the model was illustrated in a group of four patients with coronary artery disease who underwent revascularization.  相似文献   

17.
Thinning of myocardial segments, mainly at the apex and basal posterior region of left ventricle, are frequent lesions in chronic chagasic cardiopathy (CCC), but still without a well determined etiology. Previously we found severe myocardial microvascular dilatation that could cause ischemia in watershed regions. In this study we analyzed whether narrowness in epicardial coronary arteries in CCC might explain these thinned ventricular lesions. Two groups of dilated hearts with similar weights were compared: eleven hearts from patients with CCC versus four hearts from patients with dilated cardiomyopathy (IDCM). As normal controls we studied three non dilated normal weight hearts. There were no atherosclerotic plaques in the main branches of epicardial coronary arteries and cross-sectional luminal areas of proximal and distal segments were histologically measured. It was found that CCC hearts presented a lower mean luminal area in the right coronary artery (RCA) branch than IDCM, in proximal (4.3 +/- 1.4 vs 6.6 +/- 2.0 mm2; p=0.02) and in distal (1.6 +/- 1.0 vs 3.4 +/- 0.9 mm2; p=0.01) segments, with no statistical differences with normal hearts (2.7 +/- 1.3 and 1.5 +/- 0.3 mm2) in proximal (p=0.2) and distal (p=0.11) sections. In conclusion thinning of ventricular wall in CCC patients seems to be ischemic lesions in the peripheral territory irrigated by the right coronary artery, possibly due to a steal phenomenon by the left coronary, induced by micro vessels dilatation.  相似文献   

18.
Percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) was performed in 42 patients (37 males, 5 females, average age 53 years). Recanalization of the stenosed or occluded infarction-related coronary artery was achieved within the first 14 to 50 min from the start of catheterization in 95% of cases. Three patients were transferred for emergency coronary bypass graft surgery (CABG) because of major multiple coronary lesions, immediately after angiographically successful PTCA. One of the patients died in cardiogenic shock. Four patients died between days 5 to 15 of hospitalization. Repeat coronary angiography was done in 27 of the 37 survivors at a mean interval of 2.5 months after AMI. Total reocclusion was found in 6 patients. The recanalized coronary artery had prevented its patency in 78% of the cases; restenosis was found in 5 patients, and was successfully dealt with renewed angioplasty in 3 patients. While the ejection fraction (EF) had remained largely unchanged, there was some improving tendency of left ventricular segmental kinetics, particularly in case of anterior wall infarction. PTCA without thrombolytic therapy seems to provide an effective and relatively prompt recanalizing procedure in the complex management of AMI.  相似文献   

19.
The “metamorphosis” of acute myocardial infarction (AMI) in terms of pathological features and complications in the reperfusion era is herein discussed. Typically, the AMI following coronary artery recanalization is characterized by frequent subendocardial location, since a prompt coronary lumen recanalization is able to prevent the transmural progression of myocardial necrosis from the endocardium towards the epicardium. Transmural AMI may develop when recanalization occurs late (>6 hours) or is not effective (persistent coronary occlusion). Moreover, reperfused AMI frequently appears reddish because of interstitial haemorrhage, which is thought to be caused by vascular cell damage with leakage of blood out of the injured vessels. Hemorrhage occurs always within the area of necrosis and it is significantly related to the infarct size and to the coronary occlusion time. At histology, typical features of reperfused AMI consist of contraction band necrosis and interstitial hemorrhage. Moreover, a more pronounced inflammatory cellular response is visible within the necrotic area when comparing reperfused with non-reperfused AMI. Reperfusion after prolonged coronary occlusion is also associated with secondary impairment of microcirculatory flow (“no-reflow” phenomenon), that is due to endothelial swelling, luminal obstruction and external compression but may also be aggravated by distal embolization. Finally, the reperfused AMI with its typical subendocardial, non-trasmural location, is characterized by a lower incidence of expansive remodelling and related complications, in terms of cardiogenic shock, myocardial rupture, aneurysm and pseudoaneurysm formation and thromboembolism. Moreover, pericardial involvement is a rare occurrence. Unfavorable mechanical consequences of intramyocardial haemorrhage could consist in increased myocardial stiffness, propensity to wall rupture and delayed healing process. However, prospective in vivo large-scale studies in patients with reperfused AMI are needed to assess the prognostic value of hemorrhagic AMI in terms of morbidity and mortality. The knowledge and correct interpretation of these findings at post-mortem by the general and forensic pathologists is of great importance, to provide useful information to the clinicians.  相似文献   

20.
择期经皮冠脉介入术对急性心肌梗死心肌微循环的作用   总被引:1,自引:0,他引:1  
目的应用心肌声学造影(MCE)评价急性心肌梗死(AMI)患者择期经皮冠脉介入术(PCI)前后的心肌微循环。方法选择20例AMI患者,在择期PCI治疗前、后分别应用声诺维(SonoVue)静脉注射,行间歇触发、二次谐波MCE检查,应用声学密度分析软件(AD)定量测定心肌微循环内造影剂的声学峰值强度(PI)、曲线下面积(AUC)。结果治疗前梗死相关节段的PI、AUC明显低于正常灌注节段(P<0.001);择期PCI治疗后梗死节段的PI、AUC仍明显低于正常节段(P<0.001),但较PCI前明显升高(P<0.001),校正后的PIr、AUCr亦明显升高(P<0.001);而正常灌注节段的PI、AUC在PCI前后无明显变化(P>0.05)。结论MCE可定量评定AMI患者的心肌微循环;择期PCI可改善AMI患者梗死节段的微循环。  相似文献   

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