ST Elevation Myocardial Infarction With No Structural Lesions After a Wasp Sting

Background: Acute coronary syndromes after hymenoptera stings and other environmental exposures are referred to as the Kounis syndrome or allergic myocardial ischemia and infarction. Case Report: We report the case of a 58-year-old man with transient inferior ST-segment elevation consistent with myocardial ischemia after a single wasp sting. Urgent cardiac catheterization revealed normal coronary arteries with a normal left ventriculogram. The evaluation and treatment of cardiac ischemia associated with an allergic reaction is discussed. Conclusion: ST elevation myocardial infarction after wasp envenomation is an exceptional and interesting pathology with a partially elucidated pathogenesis. The management of cardiac ischemia in this setting is uncertain.     

A potential diagnostic pitfall in acute chest pain: Massive pulmonary embolism mimicking acute STEMI

Background

Pulmonary embolism (PE) represents a clinical challenge for clinicians because of nonspecific presentations, including dyspnea, chest pain, and tachycardia. The immediate 12-lead electrocardiogram (ECG) is commonly used to facilitate differential diagnosis of acute chest pain. Although relative rare, massive pulmonary embolism could induce ST segment elevation and mimic acute myocardial infarction.

非ST段抬高急性冠脉综合征危险分层的现状与展望

急性冠脉综合征（Acs）是指冠状动脉血流突然受阻致急性心肌缺血的临床病症,现已成为影响人类身心健康的一个社会公共问题。根据发病时的心电图特征,临床上将ACS分为非ST段抬高和ST段抬高2种。由于非ST段抬高ACS（NSTE-ACS）冠脉存在严重狭窄,且心电图改变常常为一过性或短暂ST段压低,或T波倒置、低平,或“伪正常化”,导致临床上经常出现误诊或漏诊。而对NSTE-ACS患者进行风险评估,可以尽早筛查出高危患者。因此,本文主要对NSTE—ACS早期风险评估、出院前风险评估及现有危险分层做一综述,以便更好地了解患者所处的危险程度,指导临床策略。     

Treatment for ST-elevation myocardial infarction-bronchoscopy!

ST elevation is usually treated in cardiac catheterization laboratory with an aim for myocardial salvage by restoration of adequate coronary blood flow enhancing both early and long-term survival. Maximum benefit is achieved if therapy is initiated in the first hour after treatment onset, thus ushering the concept of door-to-balloon time. We present an interesting case of a patient whose ST elevation resolved after bronchoscopy for a lung whiteout.     

aVR导联ST段抬高预测前壁心肌梗死预后分析

目的探讨心电图aVR导联ST段抬高对急性前壁心肌梗死患者预后的价值。方法选取急性前壁心肌梗死患者65例，对其心电图和冠状动脉结果及临床资料进行对比分析。根据心电图aVR导联ST段变化分为抬高组（ST段抬高〉0．05mV）、无抬高组。结果aVR导联ST段抬高组左主干及左前降支的病变显著多于无ST段抬高组；发生多支病变和心脏不良事件多于无ST段抬高组，两组有显著性差异（P〈0．05）。结论aVR导联ST段抬高对预测急性前壁心肌梗死有重要价值，临床上应高度重视。     

冠心病患者全血中miR-126表达的临床意义

目的探讨微小RNA(miR-126)在不同类型冠心病患者中的表达情况,为冠心病早期诊断、治疗及治疗后检测提供实验依据。方法将实验分成健康对照组(n=6)及冠心病组(n=36),对冠心病组(分为稳定性心绞痛组,不稳定性心绞痛组,非ST段抬高性心肌梗死组,ST段抬高性心肌梗死组,每组9例)接受经皮冠状动脉介入治疗(PCI)术前,术后第1天,术后第5天等时间点的观察。应用实时荧光定量PCR(qRT-qPCR)技术检测确诊为不同类型冠心病患者术前、术后全血标本中miR-126的表达量。结果 qRT-qPCR结果显示:①健康对照组、稳定性心绞痛组、不稳定性心绞痛组3组miR-126的表达量无显著性差异,但在急性心肌梗死组(包括非ST段抬高性组、ST段抬高性组)患者中miR-126的表达量与上述三组明显减少,有显著性差异(P0.05)。②miR-126在不同时间水平有显著性差异(P0.05),ST段抬高或非ST段抬高型心肌梗死的miR-126的表达量术前明显低,术后随观察时间延长逐渐增加。③在不同时间时不同分组之间miR-126的表达量存在显著的交互效应(P0.05)。结论 miR-126在急性心肌梗死患者中及冠心病各组术前、术后的表达量明显不同,这为miR-126应用于不同类型冠心病诊断及术后疗效判断提供实验依据。     

Ambulatory ECG monitoring. How useful in detecting and quantitating transient ischemia?

ST segment shifts are reliable indicators of transient myocardial ischemia. Ambulatory ECG monitoring detects episodes of ST segment shift with and without chest pain in patients with coronary heart disease. Monitoring can provide valuable information on the presence and frequency of transient myocardial ischemia. Limited information is available on the use of ambulatory monitoring as a screening test, particularly in populations where the frequency of coronary heart disease is low.     

Primary Angioplasty in Patient with St-Segment Elevation Myocardial Infarction in the Setting of Intentional Carbon Monoxide Poisoning

Background

ST-segment elevation myocardial infarction (STEMI) due to coronary artery occlusion in the setting of acute carbon monoxide (CO) poisoning is a very rare presentation.

Objective

Our aim was to report on the use of primary angioplasty in a patient with STEMI in the setting of CO poisoning.

Case Report

A 36-year-old man with retrosternal chest pain was admitted after exposure to CO. The initial electrocardiogram (ECG) showed ST depression in I, aVL, and V3−V4 with slight ST elevation in II, III, aVF leads. Toxic carboxyhemoglobin level of 22% and troponin I of 2.19 μg/L were confirmed. After oxygen therapy the chest pain diminished, but after about 15 h it returned. The repeat ECG revealed normalization of previous ST depression with persistent ST elevation in II, III, aVF leads. The troponin I concentration was 5.94 μg/L. An echocardiogram demonstrated an apex hypokinesia involving the adjacent segments of the anterior and lateral wall. On the coronary angiogram, an acute occlusion of the distal left anterior descending coronary artery was confirmed. Primary percutaneous coronary intervention (PCI) of the infarct-related artery was performed. After PCI, the patient was symptom free and had partial ST-segment elevation resolution. The patient was discharged home after 7 days, with persistent ST-T changes and mild hypokinesia of the apex suggesting myocardial injury.

Conclusions

Patients with toxic CO exposure who have symptoms of STEMI should be carefully evaluated with serial ECG, cardiac necrosis marker measurements, and an echocardiogram. When there is evidence of myocardial injury, a wider use of coronary angiography can identify patients who could benefit from PCI.     

Electrocardiographic Recognition of Variant Angina During Permanent Pacing

We present a patient with a permanent venlricular pacemaker who was investigated for episodes of chest pain associated with syncope. Ambulatory electrocardiographic monitoring showed essentially paced rhythm. ST segment elevation of the paced beats was observed during spontaneous chest pain, but the significance of this finding was initially unclear in the context of the abnormal repolarization associated intrinsically with paced rhythm. At angiography, coronary spasm was demonstrated after ergonovine, and this was associated with ST segment elevation during paced rhythm and with chest pain. We conclude that ST segment elevation may indicate myocardial ischemia even when observed in the face of abnormal repolarization associated with paced rhythm.     

The initial electrocardiogram in patients seen by a mobile coronary care unit

The advent of thrombolytic therapy for patients with suspected acute myocardial infarction has highlighted the importance of the initial electrocardiogram (ECG) in decision making. Thus we analysed the initial ECGs of 94 consecutive cases with suspected myocardial infarction who were seen within six hours after the onset of chest pain by a mobile coronary care unit. The study included 91 patients (three patients admitted twice) (61 male), aged 27-83 years (mean 60.5). Median time from onset of chest pain to arrival of the mobile coronary care unit was 75 minutes (range 15-345), and mean mobile coronary care unit response time was 12.3 +/- 7 (SD) minutes (range 5-45). The majority of cases (65 of 94, 69.1 per cent) were seen within two hours of the onset of symptoms. A final diagnosis of myocardial infarction was made in 48 of 94 (51.1 per cent) cases; 38 had unstable angina and eight other diagnoses. Of the 48 with myocardial infarction the initial ECG showed ST segment elevation in 37, ST depression and or T wave inversion in six, Q waves only in three and left bundle branch block in two. No patient with an initially normal ECG had a myocardial infarction. Thrombolytic therapy was given out of hospital to 33 of 38 patients with ST segment elevation. In seven patients with ST elevation (median delay time to intensive care 60 minutes), rapid resolution of ST segment elevation occurred following thrombolytic therapy and there was no significant elevation of cardiac enzymes, suggesting that the infarct had been aborted.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ecstasy‐induced acute coronary syndrome: Something to rave about

Ecstasy or 3,4‐methylenedioxymethamphetamine is a commonly used illicit recreational drug, enjoying popularity for its stimulant effects. Although acute coronary syndrome is recognized after cocaine and methamphetamine use, association with Ecstasy use has rarely been reported. We report three cases of significantly delayed acute coronary syndrome and ST elevation myocardial infarction related to ingestion of Ecstasy.     

Posterior myocardial infarction with isolated ST elevations in V8 and V9: Is this an "ST elevation MI"?

We report a case of a 53-year-old man whose first manifestation of coronary artery disease was an acute isolated posterior myocardial infarction (IPMI). Acute IPMI is relatively uncommon and predominantly due to occlusion of the left circumflex coronary artery. IPMI is challenging to diagnose due to the absence of ST segment elevation on a standard 12-lead electrocardiogram (ECG) even in the setting of total coronary artery occlusion and transmural (Q-wave) infarct. We discuss the diagnostic implications of the absence of tall R waves in leads V1 and V2 on this patient's ECG. The utility of posterior leads (V7 through V9) is demonstrated. The controversy surrounding the use of thrombolytic therapy or primary angioplasty in the setting of acute IPMI without ST segment elevation on a standard 12-lead ECG is reviewed.     

Immediate diagnosis of acute inferior wall myocardial infarction with electrocardiographic pattern of only R-wave loss in inferior leads: a case report

The 12-lead electrocardiogram is an easily obtained, non-invasive method to assist in the diagnosis of an acute myocardial infarction. Traditional electrocardiographic criteria for diagnosing inferior myocardial infarction emphasize abnormalities of the initial large Q wave or ST segment elevation in leads II, III, and aVF. We report a case that has acute R-wave loss in inferior leads as an initial manifestation of acute inferior wall myocardial infarction. The patient was stabilized by coronary angioplasty.     

News in brief

This perspective makes a contentious viewpoint that ECG information is underutilized in ST-segment elevation myocardial infarction (STEMI) and the next breakthrough rests on its full utilization. This is to better diagnose difficult cases such as ST changes during bundle branch block, posterior ST elevation and right-sided ST elevation during normal conduction, and aVR ST elevation. More importantly, this is to better characterize the STEMI for tailored reperfusion. The proposal is to develop a system capable of recording from multiple electrodes that one can apply onto oneself, and having analysis coordinated centrally via phone-internet transmission. This provides ‘longitudinal’ in addition to ‘cross-sectional’ ECG information. STEMI will be classified on a gray-scale according to its potential size and speed of Q wave evolution. The hypothesis is that large rapidly progressive STEMI is best treated by on-site fibrinolysis with prompt transferral to a percutaneous coronary intervention center; while small stuttering STEMI is best treated by primary percutaneous coronary intervention despite a long delay.     

Electrocardiographic changes in Takotsubo cardiomyopathy

Introduction: Takotsubo cardiomyopathy (TC) is a unique transient nonischemic cardiomyopathy that mimics acute myocardial infarction (MI). The aim of our study was to evaluate electrocardiographic changes in patients with TC, including the frequency of ST elevation and other abnormalities. Methods : Eleven patients were retrospectively identified from echocardiography database. All patients underwent coronary angiography and fulfilled the Mayo criteria for diagnosis of TC during the period November 2005 to September 2010. Standard 12‐lead electrocardiograms recorded daily during the first week of hospitalization, after onset of symptoms were analyzed. Results: Eight of 11 patients were found to have ST elevation, of which two patients had ST depression in reciprocal leads. No patient had ST elevation in lead V1, most likely reason being that wall‐motion abnormalities in TC rarely extend to the region faced by lead V1. Pathological Q waves were found in five patients, of which two patients had transient Q waves, suggesting less myocardial damage. All 11 patients had T‐wave inversion; eight of these patients had diffuse symmetric T‐wave inversion, extending beyond the perfusion territory of any single coronary artery. QTc interval prolongation was found in 10 patients. All patients had left ventricular ejection fraction between 25% and 35% on presentation, which could not be predicted by the extent of electrocardiogram (ECG) changes. Conclusion: ECG changes in TC are distinctive and differ from those typically seen in acute anterior MI. The ECG abnormalities described may be important clues for the clinician to suspect diagnosis of TC in the right clinical setting. (PACE 2011; 34:1278–1282)     

Initial experience with the Endicor X-sizer thrombectomy device in patients with ST segment elevation myocardial infarction

Summary We investigated 16 patients with ST segment elevation myocardial infarction who had an occluded coronary artery (TIMI 0) at initial angiogram. Instead of balloon angioplasty and stenting, patients were subjected to thrombectomy (Endicor X-sizer) and stenting. In 15/16 patients the occlusion could be crossed by the thrombectomy device resulting in TIMI flow 3 in all of them. Thereafter, stenting was performed. At final angiogram all 15 patients continued to show TIMI flow grade 3. Twelve-lead ECG was performed prior to and post-intervention. ST elevation was measured as the sum of eight leads for anterior infarction and of five leads for inferior infarction. In 13/15 patients, ECG analysis was possible (2 developed bundle branch block post-intervention). In all 13 patients, a >50% ST decrease of the initial amount of ST elevation was observed reaching a >70% reduction in 11 patients. Procedural complications were low (one coronary dissection after thrombectomy) and 30 days follow-up was uneventful. Thrombectomy using the Endicor X-Sizer device may become an attractive mechanical reperfusion strategy for patients with acute myocardial infarction. Received: 29 September 2001 Accepted: 5 December 2001     

Association of transient myocardial ischemia with adverse in-hospital outcomes for angina patients treated in a telemetry unit or a coronary care unit.

BACKGROUND: Little is known about the frequency or consequences of transient myocardial ischemia in patients admitted to a telemetry unit for treatment of angina. OBJECTIVES: To compare the rate of transient myocardial ischemia in a group of patients with angina treated in a telemetry unit with the rate in a similar group treated in a coronary care unit and to determine if transient myocardial ischemia is associated with adverse in-hospital outcomes. METHODS: Continuous 12-lead electrocardiography was used to monitor changes in the ST segment in 186 patients in the coronary care unit (1994-1996) and 186 patients in the telemetry unit (1997-2000). Transient myocardial ischemia was defined as a change from baseline of 100 microV or more in the ST segment in 1 or more leads lasting 60 seconds or longer RESULTS: The rate of transient myocardial ischemia was 15% for patients in the telemetry unit and 19% for patients in the coronary care unit. Regardless of hospital unit, patients with transient myocardial ischemia were more likely than those without this complication to experience death or acute myocardial infarction after hospital admission. Most patients did not experience signs or symptoms during transient myocardial ischemia: 71% of patients in the telemetry unit versus 58% of patients in the coronary care unit (P =.28). CONCLUSIONS: Transient myocardial ischemia is common among patients with angina treated in a telemetry unit. ST-segment monitoring may be useful for detecting patients with ischemia who may benefit from more aggressive therapies aimed at abolishing ongoing ischemia.     

Acute ST‐elevation myocardial infarction in a 24‐year‐old woman with atheromatous coronary artery disease

We report the case of a 24‐year‐old Torres Strait Islander woman who presented to a rural hospital ED with chest pain suspicious for myocardial ischaemia and was found to have an anterior ST‐elevation myocardial infarction. She was thrombolysed and transferred to a tertiary centre where subsequent angiography revealed atheromatous disease of the left anterior descending coronary artery. We believe this to be one of the youngest reported cases of myocardial infarction due to atheromatous coronary artery disease, and demonstrates important learning points regarding the demographics and risk factors of indigenous patients with chest pain.     

Alcohol-triggered acute myocardial infarction

Heavy alcohol drinking may trigger the onset of acute myocardial infarction. Although the underlying mechanisms are poorly understood, alcohol-induced changes in blood homeostasis, endothelial dysfunction, decreased fibrinolysis, and coronary spasm are the possible explanations. There are rare reports of acute myocardial infarction in young individuals triggered by acute heavy alcohol intake. We present a case of acute ST segment elevation myocardial infarction triggered by heavy alcoholic binge drinking in a man and discuss the available explanations of this rare association.