Value of serial P wave changes in indicating left heart failure in myocardial infarction

In order to evaluate ventricular failure in acute myocardial infarction, electrocardiographic left atrial overloading was correlated to several simultaneous clinical and radiological signs of left ventricular dysfunction in 200 consecutive patients. Analyses were made at three time periods after infarction. Left atrial overloading, measured by P terminal force, was significantly associated with the signs of left ventricular dysfunction, though in this unselected series of infarctions the prevalence of abnormal values was not high (46%). This finding is to be considered rather as a contributory sign than as a diagnostic one in the entire clinical picture. In an individual patient, however, conspicuous serial changes are helpful in indicating the direction of course of the haemodynamic disorder. The prognostic value of the P terminal force was found to be significant.     

急性心肌梗死合并急性左心衰竭临床分析

急性心肌梗死(AMI)合并急性左心衰竭不仅病死率高,而且AMI不易及时诊断导致延误治疗,尤其是非ST段抬高性心肌梗死(NSTEMI)易被忽视,同时合并症多.通过对46例AMI合并急性左心衰竭的病例进行回顾性分析,以期对此类AMI患者的及时诊断及治疗提供参考.……     

Epidemiology of heart failure and left ventricular dysfunction after acute myocardial infarction

The development of heart failure and/or left ventricular systolic dysfunction has long been regarded as an ominous complication, significantly increasing the morbidity and short- and long-term mortality of survivors of acute myocardial infarction. Although the incidence of heart failure after myocardial infarction has fallen over the last few decades, it remains common, complicating up to 45% of infarcts. Moreover, up to 60% of myocardial infarcts will result in left ventricular systolic dysfunction, depending on the exact definition used. Those at greatest risk of developing heart failure are the elderly, females, and those with prior myocardial infarction. Advances in the management of acute myocardial infarction have led to reduced in-hospital mortality (even when complicated by heart failure), but longerterm mortality remains high in these patients.     

米力农治疗急性心肌梗死并发急性左心衰竭的临床观察

目的评价米力农治疗急性心肌梗死并发急性左心衰竭的疗效及安全性。方法2005年1月2006年4月在沈阳军区总医院心内科诊断急性心肌梗死并发急性左心衰的住院患者120例,随机分为2组,每组60例,心功能均为Killip ⅢⅣ级,对照组给予常规抗心衰治疗,米力农组在常规治疗的基础上加用米力农0.5μg/（kg.min）静脉滴注5 h,每日1次,应用7 d。观察患者用药前后的症状变化、心功能级别及不良反应。结果米力农组心功能改善总有效率为88%,对照组为70%,两组总有效率有显著差异（P<0.05）。米力农组无明显药物不良反应。结论米力农治疗急性心肌梗死并发急性左心衰疗效确切、安全可靠。     

Neuroendocrine prediction of left ventricular function and heart failure after acute myocardial infarction

Objective—To determine the relations of plasma levels of brain natriuretic peptide (BNP), atrial natriuretic factor (ANF), N-terminal ANF (N-ANF), cyclic guanosine monophosphate (cGMP; the cardiac peptide second messenger), and plasma catecholamines to left ventricular function and to prognosis in patients admitted with acute myocardial infarction.
Design—Plasma hormones and ventricular function (radionuclide ventriculography) were measured 1-4 days after myocardial infarction in 220 patients admitted to a single coronary care unit. Radionuclide scanning was repeated 3-5 months after infarction. Clinical events were recorded over a mean period of 14 months.
Results—Both early and late left ventricular ejection fraction (LVEF) were most closely related to plasma BNP (r = −0.60, n = 220, p < 0.001; and r = −0.53, n = 192, p < 0.001, respectively), followed by ANF, N-ANF, cGMP, and the plasma catecholamines. Early plasma BNP concentrations less than twofold the upper limit of normal (20 pmol/l) had 100% negative predictive value for LVEF < 40% at 3-5 months after infarction. In multivariate analysis incorporating all the neurohormonal factors, only BNP remained independently predictive of LVEF < 40% (p < 0.005). Survival analysis by median levels of candidate predictors identified BNP as the most powerful discriminator for death (p < 0.0001). No early deaths (within 4 months) occurred in patients with plasma BNP concentrations below the group median (27 pmol/l), and over follow up only three of 26 deaths occurred in this subgroup. Of all episodes of left ventricular failure, 85% occurred in patients with plasma BNP above the median (p < 0.001). In multivariate analyses, BNP alone gave additional predictive information beyond sex, age, clinical history, LVEF, and plasma noradrenaline for both subsequent onset of LVF and death.
Conclusions—Plasma BNP measured within 1-4 days of acute myocardial infarction is a powerful independent predictor of left ventricular function, heart failure, or death over the subsequent 14 months, and superior to ANF, N-ANF, cGMP, and plasma catecholamines.

Keywords: cardiac natriuretic peptides; noradrenaline; myocardial infarction; heart failure     

P向量环对左房肥大的诊断价值

为探讨VCG P环变化对左房肥大的诊断价值,观察100例器质性心脏病及40例正常人VCG之P环变化、ECG之P波改变,并与UCG所测左房大小对比分析.结果:VCG诊断标准横面P环指向左后方,最大P向量(-10°——90°),振幅>0.10mV,敏感性(81.6%)明显高于ECG标准PTFv_1<-0.03mm·s(59.2%)(P<0.05),而两种标准的特异性相近.提示部分左房肥大ECG V_1导联P波尚未出现变化时VCG横面P环已有明显改变.     

Pathophysiology of heart failure following myocardial infarction

The structural and functional abnormalities that lead to cardiac death are coronary artery disease and left ventricular abnormalities related to remodelling (left ventricular hypertrophy, left ventricular systolic dysfunction, and left ventricular fibrosis). Aldosterone adversely affects all of these processes. It produces both a vasculopathy and left ventricular dysfunction and fibrosis. Endothelial dysfunction in the coronary arteries can lead to acute coronary events. Left ventricular dysfunction will cause the progression of heart failure, and left ventricular fibrosis and dysfunction provide an arrhythmic substrate. The combination of acute coronary events and arrhythmias can lead to sudden cardiac deaths, while acceleration of the heart failure disease process can lead to deaths from progressive heart failure. The increased understanding of the mechanistic role of aldosterone in cardiovascular disease provides a rationale for the positive results that have been seen in clinical trials of aldosterone blockade.     

N末端B型利钠肽原在陈旧性心肌梗死患者中诊断心力衰竭的价值

目的 评价血浆N末端B型利钠肽原(NT-proBNP)在陈旧性心肌梗死(OMI)患者中诊断失代偿性心力衰竭(心衰)的价值.方法 连续检测586例OMI患者入院时的血浆NT-proBNP浓度.依据NYHA心功能分级标准评价患者的心功能.心衰组为NYHA心功能Ⅱ级、Ⅲ级和Ⅳ级的患者,非心衰组为NYHA心功能I级的患者.通过ROC曲线下面积评价血浆NT-proBNP浓度诊断失代偿性心衰、左心室收缩功能不全和左心室扩大的价值,并找出其诊断失代偿性心衰的切点.结果586例 OMI患者中,男性占80％,年龄25～83岁,平均(58±11)岁.NYHA Ⅰ级374例、Ⅱ级99例、Ⅲ级82例、Ⅳ级31例,其血浆NT-proBNP浓度[中位数(第25百分位数,第75百分位数)]分别为[484.7(381.6,647.8)pmol/L、907.6(516.6,1290.3)pmol/L、1420.2(879.5,2336.2)pmol/L2442.6(1695.4,3670.7)pmol/L,P＜0.01].心衰组(212例)血浆NT-proBNP浓度显著高于非心衰组(374例)[分别为1148.2(707.9,2145.3)pmol/L和484.7(381.6,647.8)pmol/L,P＜0.01].60岁以上的OMI患者的血浆NT-proBNP显著高于＜60岁的患者[分别为702.3(472.4,1208.5)pmol/L和526.6(392.1,855.6)pmol/L,P＜0.01].男女性别间比较差异无统计学意义.血浆NT-proBNP诊断失代偿性心衰的ROC曲线下面积是0.844(95％ CI:0.809～0.880,P＜0.01).根据ROC曲线,将NT-proBNP诊断失代偿性心衰的切点值定为700 pmol/L,大于或等于此值时诊断心衰的敏感性、特异性和准确性分别是75.9％、79.9％和78.3％,阳性预测值和阴性预测值分别为67.9％和85.3％.对于＜60岁患者,该切点值以600 pmol/L最佳,对于≥60岁患者,该切点值以800pmol/L为最佳.结论 血浆NT-proBNP是OMI患者中诊断失代偿性心衰的可靠指标.对≥60岁和＜60岁的患者应采取不同的诊断切点.     

Progressive heart failure after myocardial infarction in mice

We tested the hypotheses that myocardial infarction in mice would lead to progressively worsening heart failure 12–18 weeks later and that exercise testing would provide a suitable means to evaluate left ventricular function sequentially. C57BL/6 mice (n = 69) underwent left coronary artery ligation (n = 50) or thoracotomy without ligation (n = 19). Sixteen animals (32 %) died within 24 h of coronary ligation. Twenty additional animals (40 %) died between days 3 and 14, and these mice showed infarct sizes of > 50 % of the left ventricle. Fourteen animals (28 %) that survived two weeks underwent echocardiography and treadmill testing 12 and 18 weeks after infarction, with no further mortality. Mice were then killed, morphometric assessment made, infarct size evaluated, and myocardial norepinephrine content and expression of BNP and ANF measured. Mice with infarcts >30 % of the left ventricle (n = 6; 12 % of original cohort) had left ventricular dilation (p < 0.0001) and hypertrophy (p < 0.001), impaired left ventricular systolic function (p < 0.0001) and reduced exercise duration (p = 0.03) and total work (p = 0.03) 12–18 weeks after infarction. Mice with infarcts < 30 % of the left ventricle (n = 8; 16 % of original cohort) had no significant functional changes or left ventricular remodeling. Hearts from mice with infarcts > 30 % had reduced myocardial norepinephrine levels (MI < 30 %: 177 ± 54 pg/mg, n = 6; MI > 30 %: 66 ± 14 pg/mg wet weight, n = 4; p = 0.005) and increased mRNA content of BNP (p < 0.03) and ANF (p = 0.023). Coronary artery occlusion in mice provides a relevant model of clinical heart failure that is progressive and can be assessed by sequential exercise testing, providing a means to study the development of heart failure and its treatment. Received: 3 October 2001, Returned for revision: 22 October 2001, Revision received: 3 December 2001, Accepted: 12 December 2001     

急性下壁ST段抬高型心肌梗死患者左心衰竭的危险因素分析

目的 探讨急性下壁ST段抬高型心肌梗死患者发生左心衰竭的影响因素,为临床防治措施的制定提供依据.方法 将沧州市人民医院2013年1月至2018年1月收治的534例急性下壁ST段抬高型心肌梗死患者作为此次研究对象,回顾性分析这些患者的临床病历资料,并查阅患者病史等,将发生心力衰竭的患者(162例)作为观察组,将未发生心力...     

Interleukin-10 improves left ventricular function in rats with heart failure subsequent to myocardial infarction

Evidence has shown that pro-inflammatory cytokines, especially TNF-alpha, are involved in the inflammatory response in the remodelling process after myocardial infarction (MI). Although IL-10, an anti-inflammatory cytokine, has been shown to antagonize some of the deleterious effects of TNF-alpha, little is known about its role in post-MI left ventricular (LV) dysfunction. The aim of the present study was to investigate whether a therapy with rhIL-10 could be beneficial in an animal model of post-MI heart failure (HF). Rats with experimental MI were treated with rhIL-10 (75 microg/kg/d sc) starting directly after MI induction, and continuing for 4 weeks. Controls were untreated MI and sham-operated rats. Cardiac function was assessed by echocardiography and cardiac catheterization 4 weeks after MI induction. Membrane-bound and soluble fractions of TNF-alpha, IL-6 and IL-10, the ratio of TNF-alpha to IL-10, serum levels of MCP-1 as well as myocardial macrophage infiltration, were analyzed. Treatment with rhIL-10 significantly improved post-MI LV function (FS +127%;, dP/dt(max) +131%; LVEDP -36%). This effect was associated with a significant decrease in pro-inflammatory cytokine and chemokine levels (TNF-alpha, IL-6, MCP-1) and furthermore resulted in a reduced myocardial infiltration of macrophages.     

Aldosterone blockade in post-acute myocardial infarction heart failure

Development of heart failure (HF) or left ventricular systolic dysfunction (LVSD) significantly increases mortality post acute myocardial infarction (AMI). Aldosterone contributes to the development and progression of HF post AMI, and major guidelines now recommend aldosterone blockade in this setting. However, lack of practical experience with aldosterone blockade may make clinicians hesitant to use these therapies. This review is based on a consensus cardiology conference that occurred in May 2005 (New York City) concerning these topics. Potential barriers to the use of aldosterone blockade are discussed and an algorithm for appropriate in-hospital pharmacologic management of AMI with LVSD and/or HF is presented.     

急性心肌梗死并发急性左心衰57例临床分析

目的探讨急性心肌梗死并发急性左心衰临床特点,总结临床诊治经验。方法对我院57例急性心肌梗死并发急性左心衰患者进行回顾性分析。结果临床表现以胸闷、心前区疼痛、气促、呼吸困难为主,34例可见ST缺血改变,10例可见病理性Q波,有43例cTnI高于正常。结论急性心肌梗死并发急性左心衰病情危急,临床表现多样,及时治疗是关键。