Myocardial Infarction with Nonobstructive Coronary Arteries: The Importance of Achieving Secondary Prevention Targets

Background

Approximately 5% to 10% of all patients with myocardial infarction have nonobstructive coronary arteries. Studies investigating the importance of follow-up and achievement of conventional secondary prevention targets in these patients are lacking.

Office Management after Myocardial Infarction

Patients should have their modifiable coronary artery risk factors intensively treated after myocardial infarction. Hypertension should be treated with beta-blockers and angiotensin-converting enzyme inhibitors. The blood pressure should be reduced to less than 140/90 mm Hg or to less than 130/80 mm Hg in patients with diabetes or chronic kidney disease. The serum low-density lipoprotein cholesterol should be reduced to less than 70 mg/dL with statins if necessary. Diabetic patients should have their hemoglobin A_1c reduced to less than 7.0%. Aspirin or clopidogrel, beta-blockers, and angiotensin-converting enzyme inhibitors should be given indefinitely unless contraindications exist to their use. Long-acting nitrates are effective anti-anginal and anti-ischemic drugs. After an infarction, patients at very high risk for sudden cardiac death should receive an implantable cardioverter-defibrillator. The 2 indications for coronary revascularization are prolongation of life and relief of unacceptable symptoms despite optimal medical management.     

辛伐他汀改善心肌梗死后心肌胶原含量变化及机制的实验研究

目的:探讨辛伐他汀对大鼠心肌梗死后心肌胶原含量的影响及其机制. 方法:建立大鼠心肌梗死模型,24 h后存活大鼠随机分成心肌梗死组(n=9)、辛伐他汀20 mg组[20 ms/(kg·d),n=10]和平伐他汀40 mg组[40 ms/(kg·d),n=9],另设假手术组(n=10).4周后观察血脂水平、左心室重指数和天狼猩红染色分析左心室非梗死区心肌胶原容积分数(表达心肌胶原含量),免疫组化检测基质金属蛋白酶-2(MMP-2),免疫印迹杂交方法(Western blot)和逆转录多聚酶链反应(RT-PCR)检测转化生长因子β1(TGF-β1)在非梗死区的表达. 结果:①各组血脂水平差异无统计学意义,心肌梗死组左心室重苗指数、非梗死区Ⅰ型、Ⅲ型胶原容积分数及Ⅰ型与Ⅲ型胶原容积分数比值较假手术组均明显升高(P均<0.05),差异均有统计学意义;辛伐他汀两组左心室重量指数、非梗死区Ⅰ型、Ⅲ型胶原容积分数及Ⅰ型与Ⅲ型胶原容积分数比值较心肌梗死组均卜降,但仍高于假手术组(P均<0.05),差异均有统计学意义.②心肌梗死组MMP-2和TGF-β1表达较假手术组均显著增加(P均<0.05),而辛伐他汀两组表达则明显降低,但仍高于假手术组(P均<0.05),差异均有统计学意义. 结论:辛伐他汀能有效改善大鼠心肌梗死后心肌胶原含量,机制与其渊脂作用无关,可能与下调MMP-2和TGF-β1的表达有关.     

Smoking Status and Incidence of Cancer After Myocardial Infarction: A Follow-Up Study of over 20 Years

Objectives

We evaluated long-term incidence of cancer after myocardial infarction among current, former, and never smokers, and assessed whether reducing cigarette consumption is associated with decreased cancer risk.

低剂量多巴酚丁胺负荷超声心动图预测初发急性心肌梗死后心室壁运动障碍的改善

目的：探讨低剂量多巴酚丁胺负荷超声心动图（ＬＤＤＳＥ）和９９ｍ锝甲氧基异丁基异腈（９９ｍＴｃＭＩＢＩ）心肌显像对初发急性心肌梗死患者心室壁运动障碍自发性改善的预测价值。方法：２７例初发急性心肌梗死患者于发病后１周内行ＬＤＤＳＥ试验，并随访４个月后的心室壁运动。９例溶栓治疗患者行９９ｍＴｃＭＩＢＩ心肌显像。结果：９例溶栓治疗患者中，６例发生缺血再灌注，随访时心室壁运动障碍改善。未发生缺血再灌注的３例患者中，２例随访时心室壁运动障碍改善，１例恶化。ＬＤＤＳＥ试验对急性心肌梗死后心室壁运动障碍自发性改善预测的敏感性、特异性分别为７１％和８４％，阳性预测值和阴性预测值均为７８％。结论：ＬＤＤＳＥ试验对初发急性心肌梗死后心室壁运动障碍的自发性改善有较高的预测价值     

急性心肌梗死与血浆同型半胱氨酸的关系探讨

目的探讨急性心肌梗死（AMI）与血浆同型半胱氨酸水平的相关性。方法应用酶联免疫吸附法测定100例AMI患者和80例正常对照组血浆同型半胱氨酸水平。结果两组观察对象血浆同型半胱氨酸（Hcy）水平间差异有统计学意义（P〈0.01）;AMI组冠脉单支与多支病变患者血浆Hcy水平间差异有统计学意义（P〈0.01）。结论Hcy的浓度与血管病变支数呈正相关。     

急性心肌梗死再灌注治疗后早期ST段变化预测心肌微血管功能

目的 :评价急性心肌梗死直接经皮冠状动脉腔内成形术 (PTCA)和支架置入术后ST段变化与心肌微血管灌注之间的关系 ,探讨ST段变化预测心肌微血管功能的可行性。方法 :测量PTCA和支架置入术前及术后 1、5、10、2 0、3 0min及 12h内相关导联ST段抬高指数 (∑STI)。术后 12h内行静脉心肌声学造影 (MCE)。根据心肌灌注将 2 4例患者分为无再流者 8例 (MCE积分为 3分或 2分 ) ,再流者 16例(MCE积分为 1分 )。MCE图像用MCE图像分析软件进行定量分析。结果 :心肌梗死相关动脉成功重建后 ,16例患者危险区有再流 ,8例出现无再流现象 ;再流者 16例患者中 ,14例∑STI下降≥ 5 0 % ,而在无再流者 8例中只有 1例 (P =0 0 0 0 1) ;无再流者 7例在术后 10min内∑STI进一步抬高≥3 0 % ,而再流者仅有 2例 (P =0 0 0 3 )。∑STI变化预测心肌微血管灌注敏感性、特异性及准确性均为 87 5 % ,阳性预测值为 93 3 % ,阴性预测值为 77 8%。术后 2 0min的∑STI与标化A·β值存在显著的负相关 (γ =-0 881,P =0 0 0 0 1)。结论 :急性心肌梗死成功再灌注治疗后不同的ST段变化与心肌微血管灌注有关 ;急性心肌梗死再灌注治疗后早期ST段变化可预测心肌微血管功能。     

急性心肌梗死患者中几种炎症因子与传统心肌损伤标志物的相关性研究

目的选取多个炎症因子—基质金属蛋白酶抑制剂1(TIMP1),基质金属蛋白酶9(MMP9),新蝶呤(Neopterin),观察其在急性心肌梗死(AMI),不稳定性心绞痛、稳定性心绞痛和正常人群中的不同表达水平以及与传统心肌损伤标志物之间的相互关系,以期探索其在AMI发病进展过程中的作用和用于预测急性心梗风险的可行性。方法从收住本院的患者中,入选AMI51例,不稳定性心绞痛48例,稳定性心绞痛54例,正常人44例。所有患者的确诊依据世界卫生组织诊断标准和中华医学会的相关指南。所有患者均接受冠脉造影检查,同时采集血标本。用ELISA法分别测定4组患者的MMP9,TIMP1和Neopterin浓度。所得数据使用SPSS统计软件处理,以P0.05作为有统计学意义的显著性差异。各个数据之间的相关采用单回归线性分析检验。结果 (1)基本临床资料:四组之间在年龄和高血脂,糖尿病发病率上无显著性差异,正常组男性,高血压和吸烟史相对其他组较少。稳定心绞痛和不稳定心绞痛高血压的发生率高于急性心梗。(2)传统的心肌损伤标志物和炎症因子检测结果:高敏C反应蛋白,肌酸激酶,肌酸激酶同工酶和肌钙蛋白I,急性心梗组皆高于其他3个组,有显著性差异。而其他三组之间并无显著性差异。(3)其他炎症因子检测结果:,MMP9、TIMP1、MMP9/TIMP1以及Neopterin各个指标,AMI组皆高于其他3组,有显著性差异。其他三个组相互之间并无显著性差异。(4)入选病人的Hs-CRP与Neopterin和CK呈良好的正相关性(P0.05),而MMP9/TIMP1与hs-CRP及CK皆无相关性。Neopterin与CK也无相关性。结论在AMI患者,炎症因子MMP9、TIMP1、Neopterin均明显升高,除Neopterin与Hs-CRP有良好相关性以外,其他的炎症因子与传统的心肌损伤标志物并无相关性。     

Serum Irisin Levels,Precocious Myocardial Infarction,and Healthy Exceptional Longevity

Background

Skeletal muscles produce irisin. Growing controversy exists on the association between this myokine and chronic disease risk. On the basis of the potential protective effects that irisin could exert on both vascular function and skeletal muscle mass, we hypothesized that an elevated level of this molecule may contribute to successful aging.

Methods

Serum irisin levels were measured using enzyme-linked immunosorbent assay in disease-free centenarians, young healthy controls, and patients with precocious acute myocardial infarction.

Results

We found the highest levels of serum irisin in disease-free centenarians (35.3 ± 5.5 ng/mL) compared with young healthy controls (20.7 ± 6.3 ng/mL) and especially with young patients with acute myocardial infarction (15.1 ± 5.4 ng/mL).

Conclusions

Our study demonstrates that healthy centenarians are characterized by increased serum irisin levels, whereas levels of this molecule were found to be significantly lower in young patients with myocardial infarction. Our findings may prompt further research into the role played by irisin not only in vascular disorders but also in life span modulation.     

心肌梗死后心电图运动试验与预后分析

目的：心肌梗死后心电图运动试验各变量与预后关系尚未阐明，采用Ｃｏｘ模型，探讨心肌梗死晚期心电图运动试验与长期预后的关系。方法：对４２例心肌梗死患者进行次极量踏车运动试验，心肌梗死距心电图运动试验的平均时间为４个月（３８～１６０天）。对所有患者进行７年～９年的随访，了解其死因，采用Ｃｏｘ模型对心电图运动试验有关变量与预后进行分析。结果：随访发现心性猝死者７例，心肌再梗死死亡者４例，心力衰竭死亡者２例，取α＝０．０５，单因素分析示与预后有关的因素为年龄、运动诱发ＳＴ段压低的深度和导联数、运动中的高峰心率、心率血压双乘积、收缩压增值（回归系数分别为０．０７、０．５３、０．３、－０．０３５、－０．０００２１、－０．０４６，Ｐ均＜０．０５）；多因素分析示年龄和收缩压增值（回归系数分别为０．００８４和－０．０５，Ｐ均＜０．０５）与预后有关。结论：心肌梗死晚期心电图运动试验对预测远期心脏意外有一定价值。     

Gender Specificities in Risk Stratification After Myocardial Infarction

Objective: Although gender specificities of various risk factors have been well documented, risk stratification after myocardial infarction has never been compared in women and men. Methods: The power of left ventricular ejection fraction, heart rate variability, and mean RR interval computed from 24-hour Holter recordings, was compared in women and men for the prediction of cardiac mortality after an acute myocardial infarction. The study population consisted of 456 patients (108 women, 348 men) aged 50–75 years. Results: During a follow-up of 3 years, there were 41 cardiac deaths (13 women vs 28 men, P = NS). The positive predictive accuracy of left ventricular ejection fraction, heart rate variability, and mean RR interval at all sensitivity levels was higher in women than in men. For a 40% sensitivity, positive predictive accuracy of left ventricular ejection fraction was 46% in women and 16% in men (P < 0.05), positive predictive accuracy of mean RR interval was 90% in women and 28% in men (P < 0.05), and positive predictive accuracy of heart rate variability was 61% in women and 43% in men (P = NS). Mean RR interval had the highest positive predictive accuracy for cardiac mortality in women, but its superiority over heart rate variability was not statistically significant. In men, heart rate variability was the strongest predictor of mortality that was significantly more powerful than mean RR interval and left ventricular ejection fraction (P < 0.05). Conclusion: Increased 24-hour mean heart rate is the strongest predictor of cardiac mortality in women in whom it performs significantly better than in men. While in men, heart rate variability is a significantly better predictor of postinfarction cardiac mortality than 24-hour mean heart rate, this is not the case in women.     

冠状动脉造影正常的心肌梗塞患者核素心肌灌注显像

目的 :分析冠状动脉造影正常的心肌梗塞患者核素心肌灌注显像表现。　　方法 :回顾总结了 18例冠状动脉造影正常的心肌梗塞患者 99m锝 -甲氧基异丁基异腈 (99m Tc- MIBI)静息心肌断层显像。　　结果 :18例心肌梗塞患者心肌灌注显像均显示异常 ,12例有节段性缺损 ,6例未见缺损但可见心肌节段性稀疏。心肌灌注显像对心肌梗塞的定位与心电图 Q波比较 ,显示病变部位更明确。　　结论 :心肌灌注显像提供了冠状动脉造影正常的心肌梗塞患者心肌损伤部位及程度。     

实验性心肌梗塞后室性心动过速的低温标测与冷凝消融

对１２条犬进行了冷凝后病理学、血液动力学及动态心电图观察，另１０条犬建立心肌梗塞（简称心梗）和室性心动过速（ＶＴ）模型，并进行低温标测和冷凝消融。结果显示：①心内膜冷凝损伤灶的长、短径和深度大于心外膜冷凝（３６．６０±１１．０６ｍｍｖｓ２２．８０±３．７０ｍｍ、２９．３０±１０．９７ｍｍｖｓ１９．６０±３．１２ｍｍ、８．１４±２．４１ｍｍｖｓ５．１６±２．０３ｍｍ，Ｐ均＜０．０５），冷凝损伤灶与其周围正常心肌分界清楚。②１０条心梗犬采用电刺激或乌头碱诱发出２０次持续性ＶＴ，低温标测和冷凝消融均成功。③心外膜冷凝６条犬行动态心电图监测，均于术后３日内出现室性心律失常，７日后动态心电图检查基本恢复正常。依据上述较高的成功率、短暂致心律失常作用及无心功能障碍等可以认为低温标测和冷凝消融是治疗难治性室性心动过速的一种安全可行的方法。     

可穿戴设备在心肌梗死患者随访管理中的应用

主动健康要求个体主动获得持续的健康能力,要求慢性病患者自发和积极地关注自身健康,参与到疾病的管理中来.然而,常规随访手段不能满足心肌梗死患者的长期管理要求,患者对自己生命体征的把握,以及心血管健康状况、药物优化治疗方案和康复锻炼效果缺乏足够的了解手段.具有多种传感器的可穿戴设备为心肌梗死患者危险因素的管理、病情的监测和...     

急性心肌梗死急诊介入治疗后患者心肌灌注的动态演变

目的:观察急性心肌梗死(AMI)患者梗死相关血管再通达心肌梗死溶栓治疗临床试验(TIMI)3级血流后心肌组织灌注的动态演变,以探讨心肌无复流现象的临床特点及意义。方法:43例AMI患者,急诊冠状动脉介入治疗后梗死相关血管血流达TIMI 3级。分别于冠状动脉介入治疗后即刻、24 h内、2周和3个月时行单光子发射型计算机断层扫描(SPECT)。根据心肌灌注缺损积分,将患者分为无复流组(17例)和复流组(26例)。分析两组心肌灌注缺损积分、左心室射血分数、左心室舒张末期容积(LVEDV)和左心室收缩末期容积(LVESV)的变化规律,并进行组间比较。结果:(1)无复流组在冠状动脉介入治疗后即刻、24 h内、2周和3个月时的心肌灌注缺损积分分别为8．5±1．9, 6．4±2．3、4．6±2．1和4．2±1．7,复流组为4．1±1．0、1．7±1．2、0．5±1．1和0．4±1．0;无复流组和复流组冠状动脉介入治疗后积分在2周内均呈逐渐减低趋势,至2周时趋与稳定,2周和3个月之间比较均无显著差异(P>0．05);两组间同时相点比较,无复流组心肌灌注缺损积分在各点均显著高于复流组(P<0．01)。(2)两组左心室射血分数均呈逐渐增加趋势,但无复流组左心室射血分数较复流组恢复延迟,且在各时点均显著低于复流组。复流组冠状动脉介入治疗后左心室舒张末容积逐渐减小,无复流组则继续增加,2周时达高峰,而后开始减小,3个月时虽低于2周时,但仍显著大于冠状动脉介入治疗后24 h内(P<0．01);无复流组的左心室舒张末容积在各时相点均显著大于复流组。(3)无复流组冠状动脉介入治疗后即刻的灌注缺损积分与同时相点和3个月时的左心室射血分数均呈显著负相关(分别为r=-0．512,P< 0．05和r=-0．498,P<0．05)。结论:AMI血运重建后梗死相关血管血流达TIMI 3级的患者仍存在心肌无复流现象,但心肌无复流现象有随时间改善的趋势,至2周左右趋于稳定;早期的心肌灌注状况与后期的心功能恢复及左心室重构的发生密切相关。     

Sex Differences in Outcomes After Myocardial Infarction in the Community

PurposePrior studies observed that women experienced worse outcomes than men after myocardial infarction but did not convincingly establish an independent effect of female sex on outcomes, thus failing to impact clinical practice. Current data remain sparse and information on long-term nonfatal outcomes is lacking. To address these gaps in knowledge, we examined outcomes after incident myocardial infarction for women compared with men.MethodsWe studied a population-based myocardial infarction incidence cohort in Olmsted County, Minnesota, between 2000 and 2012. Patients were followed for recurrent myocardial infarction, heart failure, and death. A propensity score was constructed to balance the clinical characteristics between men and women; Cox models were weighted using inverse probabilities of the propensity scores.ResultsAmong 1959 patients with incident myocardial infarction (39% women; mean age 73.8 and 64.2 for women and men, respectively), 347 recurrent myocardial infarctions, 464 heart failure episodes, 836 deaths, and 367 cardiovascular deaths occurred over a mean follow-up of 6.5 years. Women experienced a higher occurrence of each adverse event (all P <0.01). After propensity score weighting, women had a 28% increased risk of recurrent myocardial infarction (hazard ratio: 1.28, 95% confidence interval: 1.03-1.59), and there was no difference in risk for any other outcomes (all P >0.05).ConclusionAfter myocardial infarction, women experience a large excess risk of recurrent myocardial infarction but not of heart failure or death independently of clinical characteristics. Future studies are needed to understand the mechanisms driving this association.     

Anxiety,Anger, and Mortality Risk among Survivors of Myocardial Infarction

Background

Although there is evidence that anxiety and anger are associated with a higher risk of cardiovascular events, studies examining the relationship between these stressors and prognosis following myocardial infarction have been mixed.

Methods

We conducted a prospective cohort study of 1968 participants (average age 60.2 years, 30.6% women) in the Determinants of Myocardial Infarction Onset Study recruited at the time of admission for myocardial infarction between 1989 and 1996. We used the state anxiety and anger subscales of the State-Trait Personality Inventory. Participants were followed for all-cause mortality through December 31, 2007 using the National Death Index. We constructed multivariable Cox proportional hazards models adjusted for demographic, behavioral, and clinical confounders and calculated hazard ratios (HR) and 95% confidence intervals (CI) to examine the relationship between high levels of anxiety and anger and all-cause mortality.

Results

Over 10 years of follow-up, 525 participants died. Compared with those scoring lower, an anxiety score >90^th percentile was associated with a 1.31-times (95% CI, 0.93-1.84) higher mortality rate. The association was apparent in the first 3 years (HR 1.78; 95% CI 1.08-2.93), but not thereafter. Likewise, an anger score >90^th percentile was associated with a 1.25-times (95% CI, 0.87-1.80) higher mortality rate. The association was higher in the first 3 years (HR 1.58; 95% CI, 0.91-2.74) than in subsequent years, but it was not statistically significant during either follow-up period.

Conclusions

In this study of myocardial infarction survivors, a high level of anxiety was associated with all-cause mortality, with the strongest association in the first 3 years of follow-up.