Additional ST-segment elevation during thrombolytic therapy in patients with acute ST-elevation myocardial infarction: impact on myocardial salvage and final infarct size

The aim of the study was to investigate the clinical significance of additional ST-segment elevation that occurs during thrombolytic therapy. Therefore, we classified 153 patients with a first acute myocardial infarction (MI) into two groups: Group A, 55 patients with additional ST-segment elevation > or = 1 mm above the initial ST elevation during thrombolytic therapy and Group B, 98 patients without this electrocardiographic pattern. Among the patients with anterior MI, Group A (n = 33) had no reduction from ST-predicted to final QRS-estimated infarct size (+12% versus -27%; p = 0.0005) and a larger final infarct size (QRS-score: 18% versus 12%; p = 0.0002) than Group B (n = 41). Among the patients with inferior MI, Group A (n = 22) had a smaller reduction from ST-predicted to final QRS-estimated infarct size (-30% versus -53%; p = 0.03) and a larger final infarct size (QRS-score: 15% versus 9%; p = 0.03) than Group B (n = 57). The area under the curve (AUC) of CK and CK-MB was higher in patients from Group A compared with those from Group B (anterior MI: AUC-CK: 22,048 versus 19,490 U.h.l-1; p = 0.07; AUC-MB: 2227 versus 2016 U.h.l-1; p = 0.11; inferior MI: AUC-CK: 17,206 versus 11,004 U.h.l-1; p = 0.01; AUC-MB: 2193 versus 1046 U.h.l-1; p = 0.007). Both global left ventricular function and ST-segment elevation resolution were significantly better in Group B. Two and three vessel disease was observed more frequently in Group A. Additional ST-segment elevation during thrombolytic therapy suggests reduced myocardial salvage by thrombolytic therapy and thus may result in larger final infarct size.     

Relationship and prognostic value of microvascular obstruction and infarct size in ST-elevation myocardial infarction as visualized by magnetic resonance imaging

Background  

Both infarct size and microvascular obstruction (MO) assessed by cardiac magnetic resonance imaging (CMR) are known to be predictors for adverse clinical outcome after ST-elevation myocardial infarction (STEMI). We hypothesized that a ratio of MO and infarct size (MO/infarct size) might be an even stronger predictor for outcome after STEMI, which has not been investigated yet.     

ST段抬高型心肌梗死患者纤维蛋白原和D-二聚体的变化

目的 探讨ST段抬高型心肌梗死(STEMI)患者与冠状动脉造影阴性者纤维蛋白原和D-二聚体含量的差异.方法 选取我院2005年1月至2007年12月诊断为STEMI并行直接经皮冠状动脉介入(PCI)治疗的患者100例.同时选取冠状动脉造影阴性者100例为对照组.比较2组间纤维蛋白原和D-二聚体含量.结果 2组性别、年龄、高血压史、糖尿病史和吸烟史差异无统计学意义(P均0.05).STEMI组血浆纤维蛋白原含量为(2.38±0.91)g/L,对照组为(2.65±0.68)g/L,差异有统计学意义(t=-2.34,P<0.05).D-二聚体的平方根STEMI组为(13.23±5.08)μg/L,对照组为(9.40±5.03)μg/L,差异有统计学意义(t=5.36,P<0.01).血浆D-二聚体与纤维蛋白原含量比值的平方根STEMI组为(9.11±4.13),对照组为(5.92±3.35),差异有统计学意义(t=5.99,P<0.01).结论 STEMI患者的纤维蛋白原低于冠状动脉造影阴性的对照组,D-二聚体高于对照组,提示在STEMI急性期存在急性血栓形成和继发纤溶.     

Fibrinolytic therapy in patients with ST-elevation myocardial infarction

ST-elevation myocardial infarction (STEMI) is related to acute occlusion of a coronary artery by a fibrin-rich thrombus. Early reperfusion in STEMI reduces infarct size and improves prognosis. Acute reperfusion may be achieved with percutaneous coronary intervention (PCI) and/or fibrinolytic agents. When performed in a timely manner, primary PCI is the preferred method of reperfusion; however, due to logistic reasons, including lack of PCI-capable hospitals and delay in the first medical contact-to-balloon time, this simplified approach lacks universal applicability. Due to clinical efficacy and the ease of administration, fibrinolysis is still an important reperfusion modality in patients with STEMI who cannot have primary PCI within guideline-recommended time. This review focuses on the role of fibrinolysis in patients with STEMI.     

Correlation of antecedent stress myocardial perfusion imaging with the infarct related artery in ST-elevation myocardial infarction

Background While stress myocardial perfusion imaging (MPI) has strong prognostic power, it predicts the site of a subsequent acute myocardial infarction (AMI) in only 47–77% of patients. Prior studies have included small number of subjects and the interval between the stress test and the AMI has varied. The objective of the present study was to further evaluate the relationship between antecedent stress MPI and subsequent AMI. Methods We screened 600 patients admitted to our institution with acute ST-elevation MI and identified 21 patients who had a stress MPI an average of 4.8 months prior to the event. The location of perfusion defects on MPI were compared to the angiographic findings at the time of the subsequent AMI. Results Sixteen patients (76%) with AMI had defects on antecedent stress MPI while 5 patients (24%) had normal scans. Reversible or fixed perfusion defects in the territory corresponding to the site of AMI were seen in 62% of patients. All 5 patients with normal scans had multiple risk factors for coronary artery disease. Conclusion Although a normal stress MPI portends an excellent outcome, a small proportion of patients with normal scans, but with risk factors go on to develop AMI. Stress MPI has reasonable power in predicting future STEMI, but a lesser degree for the location of the future MI. Complementary imaging approaches such as coronary calcium scoring or CT angiography may be beneficial in the assessment of patients at high risk for MI.     

The value of apelin-36 and brain natriuretic peptide measurements in patients with first ST-elevation myocardial infarction

BackgroundWe aimed to assess apelin—novel endogenous ligand for the angiotensin-like 1 receptor in patients with ST-elevation myocardial infarction (STEMI) and to compare its value with B-type natriuretic peptide (BNP).MethodsIn 78 consecutive patients with first STEMI treated with primary PCI, plasma apelin-36 (RIA) and BNP (MEIA) concentrations were measured twice: on admission and on the fifth day of hospitalization. Left ventricle ejection fraction (LVEF) was assessed on admission and composite endpoint (CEP)—after 1 year follow-up.ResultsDuring the 5-day interval median plasma BNP level significantly increased and median plasma apelin concentration significantly decreased. BNP, but not apelin, correlated with low LVEF (< 50%). In ROC analysis only BNP measurements were diagnostic for low LVEF. In ANOVA test, in patients with CEP, a significant decrease in apelin (but not BNP) concentrations measured in 5-day interval was found. ROC analysis identified only second BNP measurement as significant to estimate adverse outcome 0.627 in the prediction of CEP (95% confidence interval = 0.507–0.736).ConclusionFollowing STEMI there is a decrease of plasma apelin-36 concentration and an increase of plasma BNP concentration. BNP is better, than apelin diagnostic value for the detection of impaired LVEF. Both BNP and apelin have prognostic value, although both needs further evaluation.     

Serum uric acid in patients with acute ST-elevation myocardial infarction

BACKGROUND:

Few studies investigated serum uric acid levels in patients with acute Stelevation myocardial infarction (STEMI). The study was to assess the clinical value of serum uric acid levels in patients with acute ST-elevation myocardial infarction (STEMI).

METHODS:

Totally 502 consecutive patients with STEMI were retrospectively studied from January 2005 to December 2010. The level of serum lipid, echocardiographic data and in-hospital major adverse cardiovascular events (MACE) in patients with hyperuricemia (n=119) were compared with those in patients without hyperuricemia (n=383). The relationship between the level of serum uric acid and the degree of diseased coronary artery was analyzed. All data were analyzed with SPSS version 17.0 software for Student’s t test, the Chi-square test and Pearson’s correlation coefficient analysis.

RESULTS:

Serum uric acid level was positively correlated with serum triglyceride level. Hyperlipidemia was more common in hyperuricemia patients than in non-hyperuricemia patients (43.7% vs. 33.7%, P=0.047), and serum triglyceride level was significantly higher in hyperuricemia patients (2.11±1.24 vs. 1.78±1.38, P=0.014). But no significant association was observed between serum uric acid level and one or more diseased vessels (P>0.05). Left ventricular end-diastolic diameter (LVEDd) was larger in hyperuricemia patients than in non-hyperuricemia patients (53.52±6.19 vs. 52.18±4.89, P=0.041). The higher rate of left systolic dysfunction and diastolic dysfunction was discovered in hyperuricemia patients (36.4% vs. 15.1%, P<0.001; 68.2% vs. 55.8%, P=0.023). Also, hyperuricemia patients were more likely to have in-hospital MACE (P<0.05).

CONCLUSIONS:

Serum uric acid level is positively correlated with serum triglyceride level, but not with the severity of coronary artery disease. Hyperuricemia patients with STEMI tend to have a higher rate of left systolic dysfunction and diastolic dysfunction and more likely to have more in hospital MACE.KEY WORDS: Acute ST-elevation myocardial infarction, Serum uric acid, Triglyceride, Coronary angiography, Echocardiography, Left ventricular systolic dysfunction, Left ventricular diastolic dysfunction, Major adverse cardiovascular events     

Effect of infarct site on the clinical endpoints of thrombolytic-treated ST-elevation myocardial infarction

IntroductionSome studies suggest better outcomes after the use of thrombolytics in inferior ST-elevation myocardial infarction (STEMI) compared to other locations. The goal of this study is to compare the clinical endpoints of thrombolytic-treated STEMI based on coronary artery distribution.MethodsThe study population was extracted from the 2014 Nationwide Readmissions Data using the International Classification of Diseases, Ninth Revision, Clinical Modifications codes for STEMI, thrombolytic infusion, and complications of STEMI. Primary study endpoints included in-hospital all-cause mortality, length of hospital stay (LOS), cardiogenic shock, and mechanical complications of STEMI.ResultsA principal diagnosis of thrombolytic-treated STEMI was identified for in 1231 patients (mean age 61.5 years; 26.5% female). Four hundred and thirty-one STEMIs occurred in the left anterior descending (LAD) artery distribution, 124 in the left circumflex (LCX) artery distribution, and 676 in the right coronary artery (RCA) distribution. In comparison to the LAD and LCX distributions, thrombolytic-treated STEMIs in the RCA distribution were associated with lower mortality (6.5% with LAD, 5.7% with LCX, and 3.6% with RCA; p = 0.02), fewer cardiogenic shock (12.3% with LAD, 12.1% with LCX, and 7.7% with RCA; p = 0.01), and shorter LOS (4.5 days with LAD, 3.9 with LCX, and 3.6 days with RCA; p < 0.01). Mechanical complications showed no significant difference based on coronary distribution (2.3% with LAD, 3.2% with LCX, and 1.2% with RCA; p = 0.17).ConclusionsThrombolytic-treated STEMIs in the RCA distribution were associated with lower in-hospital all-cause mortality, cardiogenic shock, and shorter LOS. Mechanical complications were not different based on coronary distribution.     

肌钙蛋白I与肌酸激酶同工酶在老年人急性心肌梗死中的应用价值

目的研究肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)对老年急性心肌梗死(AMI)的诊断价值。方法选取2012年1月至2014年6月心内科临床确诊的106例老年AMI患者为AMI组,68例老年胸痛患者为胸痛组,另选取64例老年体检健康者为对照组。比较cTnI、CK-MB检测对AMI的诊断效果,并分析cTnI、CK-MB在AMI发生后不同时间段的变化情况。结果 AMI组患者血清cTnI与CK-MB水平及阳性率均高于胸痛组与对照组,差异均有统计学意义(P0.05);cTnI对AMI的诊断灵敏度、特异度及约登指数分别为92.2%、94.7%、0.869,CK-MB的上述指标分别为87.4%、90.9%、0.783,两指标联合检测的灵敏度、特异度及约登指数均有所提高;AMI组患者cTnI与CK-MB水平均在入院后12h至1d达到最高,随后下降。结论 cTnI与CK-MB联合检测对AMI的早期诊断与防治有重要的临床意义,适宜在基层医院推广应用。     

微循环障碍与急性心肌梗死患者梗死面积、心肌应变及临床预后的相关性分析

目的  分析心脏磁共振评估急性心肌梗死患者微循环障碍（MVO）与梗死面积、心肌应变及临床预后的相关性。方法  选择2022年6~12月蚌埠医学院第一附属医院收治的24例因ST段抬高型心肌梗死（STEMI）行经皮冠状动脉介入治疗术治疗的患者为对象,其中男性22例,女性2例,年龄55.3±11.3岁。所有患者于术后5~7 d进行心脏磁共振检查,根据是否出现MVO,将24例患者分为MVO组（n=16）和非MVO组（n=8）,比较两组基线资料、心功能、心肌梗死面积（LGE%）、心肌应变。对出院的STEMI患者进行平均6月的门诊或电话随访,记录心血管不良事件（MACEs）的发生情况,比较两组发生MACEs事件的差异。本研究定义的MACEs事件包括：再发胸痛、心力衰竭、脑卒中、再发心梗、出血、再次血运重建、支架内血栓、支架内再狭窄、死亡。结果  MVO组梗死节段径向应变、梗死节段周向及整体周向应变功能均低于无MVO组（P < 0.05）;MVO组心肌梗死面积大于无MVO组（25.18%±10.51% vs 9.93%±5.96%）。MVO组左心室射血分数与径向应变及周向应变呈极强相关关系[r=0.815 (0.536~0.934),P < 0.001;r=-0.938(-0.978~-0.852),P < 0.001],与纵向应变呈强相关关系[r=-0.767(-0.915~-0.437),P < 0.001]。二元回归分析中LGE%及梗死节段周向应变是STEMI患者发生MVO的独立危险因素。单因素分析ROC曲线显示,LGE%可以辅助于MVO的诊断,曲线下面积（AUC）为0.922（0.796~1.000）,其最佳截断点为14.92%,敏感度为87.5%,特异性为87.5%（P < 0.05）。梗死节段周向应变对MVO也具有诊断价值,AUC为0.781（0.591~0.971）,其最佳截断点为10.58%,敏感度为62.5%,特异性为87.5%（P < 0.05）。LGE%联合梗死节段周向应变后,其对MVO诊断的AUC及敏感度均上升,AUC为0.938（0.827~1.000）,敏感度为93.8%,特异性为87.5%（P < 0.05）。随访所有STEMI患者,10例发生MACEs事件（41.7%）,两组患者发生MACEs事件的差异无统计学意义（P=0.558）。结论  LGE%、心肌梗死节段周向应变是STEMI患者经皮冠状动脉介入治疗术后出现MVO的独立危险因素,也分别对MVO具有较高的诊断价值,两者联合诊断MVO时诊断价值更高。径向应变、周向应变、纵向应变与MVO组左心室射血分数具有较强的相关性。     

Characteristics and prognosis in patients with false-positive ST-elevation myocardial infarction in the ED

Background

There are several causes of ST-segment elevation (STE) besides acute myocardial infarction (MI).

Objectives

We design this study to determine the prevalence, etiology, clinical manifestation, electrocardiographic characteristics, and outcome in patients with false-positive STEMI.

Methods

This is a retrospective case-control study design. At our emergency department, 297 patients who underwent emergent coronary angiography for suspected STEMI were enrolled from January 2004 to December 2010.

Results

Of the 297 patients who underwent coronary angiography, 31 patients (10.4%) did not have a clear culprit coronary lesion and were classified as false-positive STEMI. False-positive STEMI patients had a lower incidence of typical chest pain or chest tightness (58.1% vs 87.6%, P < .001). Inferior STE occurred significantly more often in the patients with true-positive STEMI (49.6% vs 25.8%, P = .012), and diffuse STE, more often in the patients with false-positive STEMI (19.4% vs 0.38%, P = .001). Total height of STE was lower in false-positive STEMI patients (7.5 ± 4.9 vs 10.9 ± 7.9 mm, P = .002) if excluding 5 patients of marked STE just after cardiopulmonary resuscitation. Concave STE and no reciprocal ST-segment depression occurred more often in false-positive STEMI patients (51.6% vs 24.1%, P = .001; 64.5% vs 19.2%, P < .001). There was no significant difference of in-hospital major adverse events in the patients with false-positive and true-positive STEMI.

Conclusions

The diagnosis of false-positive STEMI is not uncommon. Detailed clinical evaluation and electrocardiogram interpretation may avoid partly unnecessary catheterization laboratory activation.     

心肌梗塞面积与信号平均心电图临床应用研究（附110例前壁梗塞患者分析）

对１１０例前壁心肌梗塞的患者应用体表心电图Ｗａｇｎｅｒ积分系统估算其心肌梗塞面积，根据其积分分成≤５分、６～９分和≥１０分３组，用信号平均心电图检测心室晚电位并作心电图监测。结果：小面积（≤５分）的心室晚电位和室性心律失常发生率最低。证实心肌梗塞面积与晚电位的产生及室性心律失常呈正相关。作者认为：体表心电图ｗａｇｎｅｒ积分判断前壁心肌梗塞面积方法简单，它有助于评价和判断患者的预后及治疗。     

Prevalence and extent of infarct and microvascular obstruction following different reperfusion therapies in ST-elevation myocardial infarction

Background

Microvascular obstruction (MVO) describes suboptimal tissue perfusion despite restoration of infarct-related artery flow. There are scarce data on Infarct Size (IS) and MVO in relation to the mode and timing of reperfusion. We sought to characterise the prevalence and extent of microvascular injury and IS using Cardiovascular magnetic resonance (CMR), in relation to the mode of reperfusion following acute ST-Elevation Myocardial Infarction (STEMI).

Methods

CMR infarct characteristics were measured in 94 STEMI patients (age 61.0 ± 13.1 years) at 1.5 T. Seventy-three received reperfusion therapy: primary percutaneous coronary-intervention (PPCI, n = 47); thrombolysis (n = 12); rescue PCI (R-PCI, n = 8), late PCI (n = 6). Twenty-one patients presented late (>12 hours) and did not receive reperfusion therapy.

Results

IS was smaller in PPCI (19.8 ± 13.2% of LV mass) and thrombolysis (15.2 ± 10.1%) groups compared to patients in the late PCI (40.0 ± 15.6%) and R-PCI (34.2 ± 18.9%) groups, p <0.001. The prevalence of MVO was similar across all groups and was seen at least as frequently in the non-reperfused group (15/21, [76%] v 33/59, [56%], p = 0.21) and to a similar magnitude (1.3 (0.0-2.8) v 0.4 [0.0-2.9]% LV mass, p = 0.36) compared to patients receiving early reperfusion therapy. In the 73 reperfused patients, time to reperfusion, ischaemia area at risk and TIMI grade post-PCI were the strongest independent predictors of IS and MVO.

Conclusions

In patients with acute STEMI, CMR-measured MVO is not exclusive to reperfusion therapy and is primarily related to ischaemic time. This finding has important implications for clinical trials that use CMR to assess the efficacy of therapies to reduce reperfusion injury in STEMI.