ECG Diagnosis and Classification of Acute Coronary Syndromes

In acute coronary syndromes, the electrocardiogram (ECG) provides important information about the presence, extent, and severity of myocardial ischemia. At times, the changes are typical and clear. In other instances, changes are subtle and might be recognized only when ECG recording is repeated after changes in the severity of symptoms. ECG interpretation is an essential part of the initial evaluation of patients with symptoms suspected to be related to myocardial ischemia, along with focused history and physical examination. Patients with ST‐segment elevation on their electrocardiogram and symptoms compatible with acute myocardial ischemia/infarction should be referred for emergent reperfusion therapy. However, it should be emphasized that a large number of patients may have ST‐elevation without having acute ST‐elevation acute coronary syndrome, while acute ongoing transmural ischemia due to an abrupt occlusion of an epicardial coronary artery may occur in patients with ST‐elevation less than the thresholds defined by the guidelines. Up‐sloping ST‐segment depression with positive T waves is increasingly recognized as a sign of regional subendocardial ischemia associated with severe obstruction of the left anterior descending coronary artery. Widespread ST‐segment depression, often associated with inverted T waves and ST‐segment elevation in lead aVR during episodes of chest pain, may represent diffuse subendocardial ischemia caused by severe coronary artery disease. In case of hemodynamic compromise, urgent coronary angiography has been increasingly recommended for these patients.     

STaVR抬高对急性冠状动脉综合征预后评估的价值

目的探讨心电图STaVR抬高对急性冠状动脉综合征预后评估的价值。方法回顾性分析68例急性冠状动脉综合征患者的心电图和冠状动脉造影资料、临床资料。根据STaVR抬高是否≥0.05mV分为抬高组（n=23）和非抬高组（n=45）。结果病变血管涉及左主干和左前降支近段的分别为抬高组13例（56.5％）和非抬高组1例（2.2％）,病变范围为多支病变的分别为9例（39.1％）和8例（17．8％）,发生心脏事件分别为7例（30.4％）和4例（8.9％）,两组差异均有非常显著性意义（P〈0．01）。结论急性冠状动脉综合征患者STaVR抬高提示左主干和左前降支近段病变、多支病变的可能,对判断预后有参考价值。     

Predictors and Implications of Q-Waves in ST-Elevation Acute Coronary Syndromes

Background

Q-waves in ST-elevation acute coronary syndromes carry adverse implications. We sought to determine the frequency, predictors, and implications of Q-waves in the current era that includes primary percutaneous coronary interventions.

Methods

There were 14,916 patients evaluated in a multicenter observational study. They presented with ST-elevation acute coronary syndromes between 1999 and 2006. Clinical variables were compared between patients with versus without presenting Q-waves, with an additional comparison in the latter group between those with versus without subsequent development of Q-waves.

Results

ST-elevation myocardial infarction occurred in 88.6% of patients. Q-waves were present on the initial electrocardiogram in 3929 patients and developed later in an additional 3085 patients. The incidence of Q-waves at presentation or during hospitalization decreased from 61% to 39% between 1999 and 2006 (linear trend P < .001). Both presenting and subsequent Q-waves were associated with greater likelihood of coronary occlusions and higher cardiac marker elevations (P <.001). Multivariate analysis showed that presenting Q-waves were associated with male sex (odds ratio [OR] 1.28), increased age (OR 1.06 per 5 years), diabetes (OR 1.26), smoking (OR 1.11), chronic aspirin (OR 0.79), acute aspirin (OR 0.87), other chronic cardiac medications (OR 0.80), prior heart failure (OR 0.67), and prior coronary artery disease (OR 0.61). Presenting Q-waves were independently associated with increased in-hospital mortality (OR 1.46), but Q-waves at presentation or during hospitalization did not impact 6-month mortality.

Conclusions

Q-waves in ST-elevation acute coronary syndromes are decreasing in incidence. Q-waves are a major determinant of in-hospital mortality, and targeted interventions should be directed to these high-risk patients.     

ST段抬高型心肌梗死诊疗策略的临床观察

目的：比较2004年与2010年ST段抬高型心肌梗死（STEMI）诊疗策略的变化,分析其与指南的差距。方法：回顾性研究152例STEMI患者（2004年37例,2010年115例）临床资料,对比分析其住院期间诊断治疗策略的差异并了解其与指南差距。结论：STEMI患者近6年来住院诊疗策略进步明显,尤其是有创检查及治疗部分,但临床实践与循证指南仍存在不少差距,特别是GPUb／Ⅲa抑制剂使用、早期再灌注治疗上仍有待提高。     

急性冠脉综合征患者血尿酸和胆红素及纤维蛋白原含量与冠脉病变程度的关系

目的探讨急性冠状动脉综合征(ACS)患者血尿酸(SUA)和总胆红素(TBil)及纤维蛋白原(FIB)含量与冠脉病变程度的关系。方法将136例ACS患者分为3组,其中急性ST段抬高心肌梗死(STEMI)患者42例(A组),急性非ST段抬高心肌梗死(NSTEMI)患者46例(B组),不稳定型心绞痛(UAP)患者48例(C组),同时选择45例正常体检者为对照组(D组),分别测定他们SUA、TBil和FIB的含量,并分析他们与冠脉病变程度的关系。结果ACS患者SUA和FIB含量均值分别为(374.0±26.5)μmol/L和(4.35±1.32)g/L,明显高于对照组SUA含量(258.6±18.4)μmol/L和FIB含量(2.26±0.82)g/L;而ACS患者TBil含量均值为(9.64±3.24)μmol/L,明显低于对照组的TBil含量(14.38±3.62)μmol/L;差异均具有显著性(P<0.01)。SUA和FIB均随冠状动脉病变程度的加重而增高,与之呈正相关(P<0.01);Bil水平随冠状动脉病变程度的加重而降低,与之呈负相关(P<0.01)。结论SUA和FIB含量的升高及Bil含量的降低与ACS的发生和冠脉病变严重程度密切相关,高SUA和FIB及低Bil是冠脉病变严重的独立危险因素。     

Long-term Outcomes of Enhanced Depression Treatment in Patients with Acute Coronary Syndromes

BackgroundThe Coronary Psychosocial Evaluation Studies trial demonstrated promising results for enhanced depression treatment to reduce cardiovascular risk of patients with acute coronary syndrome and comorbid depression, but the long-term effectiveness of this intervention is unclear.MethodsA total of 157 participants with persistent depression after hospitalization for acute coronary syndromes were enrolled in the Coronary Psychosocial Evaluation Studies trial. A total of 80 participants were allocated to 6 months of enhanced depression treatment, and 77 participants were allocated to usual care. We report on an additional 12 months of observational follow-up for the composite outcome of death or first hospitalization for myocardial infarction or unstable angina.ResultsAlthough the intervention was previously shown to have favorable cardiovascular effects during the treatment period, we observed a significant time-by-treatment group interaction during extended follow-up (P = .008). Specifically, during the 6-month treatment period, death or hospitalization for myocardial infarction/unstable angina occurred in 3 participants (4%) in the treatment group compared with 11 participants (14%) in the usual care group (hazard ratio, 0.25; 95% confidence interval, 0.07-0.90; P = .03). In contrast, during 12 months of additional observational follow-up, 11 participants (14%) in the treatment group experienced the composite outcome of death or hospitalization for myocardial infarction/unstable angina compared with 3 participants (4%) in the usual care group (hazard ratio, 2.91; 95% confidence interval, 0.80-10.56; P = .10).ConclusionsEnhanced depression treatment was associated with a reduced risk of death or hospitalization for myocardial infarction/unstable angina during active treatment, but this effect did not persist after treatment ceased. Future research is needed to confirm our findings and to determine the optimal duration of depression treatment in patients with depression after acute coronary syndromes.     

B型利钠肽在急性心肌梗死患者不同治疗方式中的变化

目的:本研究旨在通过分析急性ST段抬高心肌梗死患者基础及经皮冠状动脉介入治疗(PCI)后B型利钠肽(BNP)水平,探讨PCI治疗对BNP水平的影响及BNP与近期顶后的关系.方法:入选急性ST段抬高心肌梗死患者103例,依据入院后治疗方式分为6小时内PCI组40例,6～12小时PCI组33例,药物治疗组30例.所有患者于入院即刻、发病48小时及7天时从外周静脉中留取血样测定BNP,分别比较不同时间不同治疗方式之间BNP的差别,以及BNP与1个月时心功能的关系.所有患者均无心力衰竭、陈旧性心肌梗死及肺部、肾脏疾病史.结果:①3组患者入院即刻基础BNP水平无统计学意义(P＞0.05).发病48小时、7天时6小时内PCI组BNP水平较6～12小时PCI组均明显下降,差异均有统计学意义(P＜0.05～0.01),6小时内PCI组较药物治疗组亦明显下降,差异均有统计学意义(P＜0.05～0.01);发病48小时6～12小时PCI组BNP水平与药物治疗组相比较差异无统计学意义(P＞0.05).发病7天时6～12小时PCI组BNP水平与药物治疗组比显著下降,差异有统计学意义(P＜0.05).②发病7天时的BNP水平与1个月时心功能左心室射血分数有明显相关性(r=-0.722,P＜0.001),与Tei指数呈正相关(r=0.582,P＜0.001).③随访时发生心力衰竭、心绞痛及心血管事件的患者回顾发病7天时BNP水平明显高于未发生者(P＜0.05～0.001).结论:在急性ST段抬高心肌梗死患者中,发病7天时BNP水平与近期心功能显著相关,对近期心血管事件的发生有一定预测作用,早期PCI可以显著降低发病7天时BNP水平及降低心血管事件的发生率.     

冠脉内超声溶栓对急性心肌梗死患者胸痛、心电图和心肌酶学的影响

目的 通过研究冠脉内超声溶栓对急性心肌梗死患者胸痛、心电图和心肌酶学的影响以探讨经导管超声溶栓挽救成活心肌的意义.方法 入选急性心肌梗死患者56例(前壁心肌梗死30例,下壁心肌梗死26例).分组:超声溶栓后梗死相关血管血流达TIMI3级为溶栓成功组(A组=20例);超声溶栓后梗死相关血管血流达不到TIMI3级而后行PTCA达TIMI3级为超声溶栓+PTCA组(B组=16例);单行PTCA后梗死相关血管血流达TIMI3级为PTCA成功组(C组=20例).结果 各组发病到来院时间、来院进手术室时间和进手术室到血管开通时间均无差异.A组和B组所有患者全部达临床再通和冠脉造影再通标准,冠脉造影再通标准与临床再通标准相关性好.C组中90%患者胸痛缓解50%以上,80%患者ST段下降50%以上,100%患者心肌酶峰提前.结论低频高能超声可有效地溶解梗死相关血管内的血栓,挽救成活心肌.但超声溶栓加PTCA可能有更高的血管开通率,可挽救更多的成活心肌.     

Acute Myocardial Infarction with Severe ST Segment Elevation Treated with Percutaneous Coronary Intervention More than Two Days after Onset: A Case with Remarkable Recovery

The patient was a 65-year-old man with marked ST-elevation myocardial infarction. Cardiac catheterization revealed an occluded middle portion of the left anterior descending artery and no collateral circulation. Percutaneous coronary intervention (PCI) was performed, and ST elevation improved 5 days after PCI. Almost all electrocardiogram (ECG) findings were normal 6 months later. Echocardiographic findings were also normal. This case was very successful and unusual in that no ventricular aneurysm formed despite ST elevation continuing for a few days and that ECG and left ventricular function were nearly normal after PCI performed days after the onset in a case without collateral circulation.     

Updated Electrocardiographic Classification of Acute Coronary Syndromes

The electrocardiogram (ECG) findings in acute coronary syndrome should always be interpreted in the context of the clinical findings and symptoms of the patient, when these data are available. It is important to acknowledge the dynamic nature of ECG changes in acute coronary syndrome. The ECG pattern changes over time and may be different if recorded when the patient is symptomatic or after symptoms have resolved. Temporal changes are most striking in cases of ST-elevation myocardial infarction. With the emerging concept of acute reperfusion therapy, the concept ST-elevation/non-ST elevation has replaced the traditional division into Q-wave/non-Q wave in the classification of acute coronary syndrome in the acute phase.

Keypoints:

In acute coronary syndrome, in addition to the traditional electrocardiographic risk markers, such as ST depression, the 12-lead ECG contains additional, important diagnostic and prognostic information. Clinical guidelines need to acknowledge certain high-risk ECG patterns to improve patient care.     

Incidence,Predictors and Outcomes of Contrast Induced Nephropathy in Patients with ST Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Background:Contrast induced nephropathy (CIN) is considered one of the most common causes of hospital acquired renal failure and severely affects morbidity and mortality. Our objective was to investigate incidence, predictors and outcomes of CIN in patients with ST elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI).Methods:The study was conducted on 550 patients with STEMI subjected to PPCI. Patients were classified into two groups according to the occurrence of CIN; group I (Patients without CIN) and group II (Patients with CIN). The two groups were assessed for the clinical outcomes including mortality and major adverse cardiac events (MACE).Results:Incidence of CIN was 10.6%, multivariate regression analysis identified the independent predictors of CIN including; age > 60 years OR 6.083 (CI95% 3.143–11.77, P = 0.001), presence of diabetes mellitus OR 2.491 (CI95% 1.327–4.675, P = 0.005), non-steroidal anti-inflammatory drugs (NSAIDs) use OR 2.708 (CI95% 1.393–5.263, P = 0.003), the volume of contrast agent >200 ml OR 6.543 (CI95% 3.382–12.65, P = 0.001) and cardiogenic shock OR 4.514 (CI95% 1.738–11.72, P = 0.002). Mortality was higher in group II than group I (11.9% vs. 4.4% respectively, P = 0.015). The incidence of MACE were higher in group II than group I (heart failure; 18.6% vs. 7.3%, cardiac arrest; 8.5% vs. 2.8% and cardiogenic shock; 16.9% vs. 6.9% with P. value = 0.003, 0.024, 0.007 respectively).Conclusion:Contrast induced nephropathy was associated with increased morbidity and mortality. The independent predictors of CIN were advanced age, diabetes mellitus, NSAIDs use, the volume of contrast agent >200 ml and cardiogenic shock.     

ST‐Segment Resolution Prior to Primary Percutaneous Coronary Intervention Is a Poor Indicator of Coronary Artery Patency in Patients with Acute Myocardial Infarction

Background: The prognostic value of ST‐segment resolution (STR) after initiation of reperfusion therapy has been established by various studies conducted in both the thrombolytic and mechanic reperfusion era. However, data regarding the value of STR immediately prior to primary percutaneous coronary intervention (PCI) to predict infarct‐related artery (IRA) patency remain limited. We investigated whether STR prior to primary PCI is a reliable, noninvasive indicator of IRA patency in patients with ST‐segment elevation myocardial infarction (STEMI). Methods: The study population consisted of STEMI patients who underwent primary PCI at our institution between 2000 and 2007. STR was analyzed in 12‐lead electrocardiograms recorded at first medical contact and immediately prior to primary PCI and defined as complete (≥70%), partial (70%? 30%), or absent (<30%). Results: In 1253 patients with a complete data set, STR was inversely related to the probability of impaired preprocedural flow (P_{for trend} < 0.001). Although the sensitivity of incomplete (<70%) STR to predict a Thrombolysis in Myocardial Infarction (TIMI) flow of <3 was 96%, the specificity was 23%, and the negative predictive value of incomplete STR to predict normal coronary flow was only 44%. Conclusions: This study establishes the correlation between STR prior to primary PCI and preprocedural TIMI flow in STEMI patients treated with primary PCI. However, the negative predictive value of incomplete STR for detection of TIMI‐3 flow is only 44% and therefore should not be a criterion to refrain from immediate coronary angiography in STEMI patients. Ann Noninvasive Electrocardiol 2010;15(2):107–115     

急性下后壁伴右心室心肌梗死患者梗死相关动脉的造影特点分析

目的分析急性下后壁伴右心室心肌梗死患者,右冠状动脉作为梗死相关动脉罪犯病变造影特点。方法60例明确诊断急性下壁、正后壁或右心室心肌梗死的患者为本院2002年1月～2003年12月收入院,并接受冠状动脉造影及介入治疗的病例。最小年龄31岁,最大年龄80岁,平均年龄57±11岁。所有资料采用SAS软件处理,以P〈0.05作为有显著性差异。结果（1）临床特点：本组入选60例患者,男性占83.3%,女性占16.7%,男女比例5∶1,男性明显高于女性（P〈0.0001）。男女患者发病年龄无显著性差异（P=0.05878）。40岁以上者占绝大多数;（2）心电图特征：60例经心电图确诊的急性下壁、正后壁心肌梗死患者中,55例合并右心室梗死,占91.7%;（3）冠脉造影特征：60例患者中1例为冠状动脉左优势型,4例拒绝行冠状动脉造影。,其余55例患者梗死相关动脉均为右冠状动脉,罪犯病变在近段者18例（32.7%）,其中15例完全闭塞,中段24例（43.6%）,13例完全闭塞,远段5例（9.1%）,1例完全闭塞;后侧支3例（5.5%）,2例完全闭塞,后降支4例（7.3%）,2例完全闭塞;锐缘支1例（1.8%）,以右冠状动脉近、 中段狭窄或闭塞最常见（占76．4％）。在罪犯病变狭窄程度方面：轻、中度狭窄者5例（5．5％）;重度狭窄19例（34．5％）;完全闭塞33例（60％）;（4）左心室功能：全组平均EF正常（60％±13％）。结论在急性下、后壁伴右心室心肌梗死患者,右冠状动脉作为梗死相关动脉最为常见。罪犯病变以近、中段重度狭窄或闭塞为主。     

Warfarin Use and Outcomes in Patients with Atrial Fibrillation Complicating Acute Coronary Syndromes

Background

We examined warfarin use at discharge (according to Congestive heart failure, Hypertension, Age > 75 years, Diabetes, Prior Stroke/transient ischemic attack score and bleeding risk) and its association with 6-month death or myocardial infarction in patients with post-acute coronary syndrome atrial fibrillation.

Methods

Of the 23,208 patients enrolled in the Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy, Platelet IIb/IIIa Antagonist for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network A, and Superior Yield of the New Strategy of Enoxaparin, Revascularization and Glycoprotein IIb/IIIa Inhibitors trials, 4.0% (917 patients) had atrial fibrillation as an in-hospital complication and were discharged alive. Cox proportional hazards models were performed to assess 6-month outcomes after discharge.

Results

Overall, 13.5% of patients with an acute coronary syndrome complicated by atrial fibrillation received warfarin at discharge. Warfarin use among patients with atrial fibrillation had no relation with estimated stroke risk; similar rates were observed across Congestive heart failure, Hypertension, Age > 75 years, Diabetes, Prior Stroke/transient ischemic attack (CHADS₂) scores (0, 13%; 1, 14%; ≥ 2, 13%) and across different bleeding risk categories (low risk, 11.9%; intermediate risk, 13.3%; high risk, 11.1%). Among patients with in-hospital atrial fibrillation, warfarin use at discharge was independently associated with a lower risk of death or myocardial infarction within 6 months of discharge (hazard ratio 0.39; 95% confidence interval, 0.15-0.98).

Conclusion

Warfarin is associated with better 6-month outcomes among patients with atrial fibrillation complicating an acute coronary syndrome, but its use is not related to CHADS₂ score or bleeding risk.