Ecg changes in myocardial infarction

Timely performing electrocardiography (ECG) is crucial for early detection of ST-elevation myocardial infarction (STEMI). For shortening door-to-ECG time, a chief complaint-based “cardiac triage” protocol comprising (1) raising alert among medical staff with bedside triage tags, and (2) immediate bedside ECG after focused history-taking was implemented at the emergency department (ED) in a single tertiary referral center. All patients diagnosed with STEMI visiting the ED between November 2017 and January 2020 were retrospectively reviewed to investigate the effectiveness of strategy before and after implantation. Analysis of a total of 117 ED patients with STEMI (pre-intervention group, n = 57; post-intervention group, n = 60) showed significant overall improvements in median door-to-ECG time from 5 to 4 min ( p = 0.02), achievement rate of door-to-ECG time 10 min for those with initially underestimated disease severity (from 90 to 10%, p< 0.01) and walk-in (from 29.2 to 8.8%, p = 0.04) were both reduced. In conclusion, a chief complaint-based “cardiac triage” strategy successfully improved the quality of emergency care for STEMI patients through reducing delays in diagnosis and treatment. Primary percutaneous coronary intervention (PCI) is the gold-standard treatment for patients with ST-elevation myocardial infarction (STEMI) Rapid performance of electrocardiography (ECG) for STEMI identification is crucial to achieving coronary artery reperfusion. Some studies have sho...

Background ST elevation Myocardial infarction is a medical emergency. A variety of noncardiac conditions had been known to mimic the ECG changes that are seen in acute coronary syndrome. Although the common ECG changes that are documented with raised intracranial pressure are T inversions, prolongation of QT interval and sinus bradycardia, ST elevation or depression, arrhythmias and prominent U waves have also been recognized. However, ST elevations in association with primary intracranial tumours are rarely reported. Case presentation A 68-year-old female patient with a large left sided frontoparietal sphenoidal ridge meningioma with mass effect developed sudden onset shortness of breath while awaiting surgery. Her ECG showed ST segment elevations in the inferior leads along with reciprocal T inversions in anterior leads. The patient was treated with dual antiplatelet therapy and unfractionated heparin. The ST elevations in the ECG remained static and the cardiac Troponin assay was repeatedly negative. 2D ECHO, coronary angiogram and CT pulmonary angiography were normal. The repeat noncontract CT scan of the brain revealed two small areas of haemorrhage in the tumour. Conclusion The two mechanisms for ECG changes described in subarachnoid haemorrhage are the neurogenic stunned myocardium due to the catecholamine surge on the myocytes and stress cardiomyopathy. The same mechanisms could be the reasons for the ECG changes seen in intracranial tumours. These ECG changes coul...

An ST-elevation myocardial infarction (STEMI) is a type of heart attack that mainly affects your heart’s lower chambers. They are named for how they change the appearance of your heart’s electrical activity on a certain type of diagnostic test. STEMIs tend to be more severe and dangerous compared to other types of heart attack. Overview How a coronary artery blockage causes a STEMI heart attack. What is a STEMI? An ST-elevation myocardial infarction (STEMI) is a type of heart attack that is more serious and has a greater risk of serious complications and death. It gets its name from how it mainly affects the heart’s lower chambers and changes how electrical current travels through them. Any heart attack is a life-threatening medical emergency that needs immediate care. If you or someone you’re with appears to be having a heart attack, do not hesitate to call 911 (or the appropriate number for local emergency services). Any delay in receiving care can lead to permanent damage to the heart muscle or death. Why is it called a STEMI? Myocardial infarction is the medical term for a heart attack. An infarction is a blockage of blood flow to the myocardium, the heart muscle. That blockage causes the heart muscle to die. A STEMI is a myocardial infarction that causes a distinct pattern on an electrocardiogram (abbreviated either as ECG or EKG). This is a medical test that uses several sensors (usually 10) attached to your skin that can detect your heart’s electrical activity. That...

• ST segment elevation with subsequent Q wave formation in precordial leads (V1-6) +/- high lateral leads. These changes are often preceded by hyperacute T waves • Reciprocal ST depression in inferior leads (mainly III and aVF) NB: The magnitude of reciprocal change in inferior leads is determined by the magnitude of ST elevation in I and aVL (as these leads are electrically opposite III and aVF), and hence may be minimal or absent in anterior STEMIs that do not involve high lateral leads. Clinical Relevance of Anterior Myocardial Infarction Anterior STEMI usually results from occlusion of the A • In-hospital mortality (11.9 vs 2.8%) • Total mortality (27 vs 11%) • Heart failure (41 vs 15%) • Significant ventricular ectopic activity (70 vs 59%) • Lower ejection fraction on admission (38 vs 55%) In addition to anterior STEMI, other high-risk presentations of anterior ischaemia include Patterns of Anterior Infarction The nomenclature of anterior infarction can be confusing, with multiple different terms used for the various infarction patterns. The following is a simplified approach to naming the different types of anterior MI. The precordial leads can be classified as follows: • Septal leads = V1-2 • Anterior leads = V3-4 • Lateral leads = V5-6 The different infarct patterns are named according to the leads with maximal ST elevation: • Septal = V1-2 • Anterior = V2-5 • Anteroseptal = V1-4 • Anterolateral = V3-6, I + aVL • Extensive anterior / anterolateral = V1-6, I + aVL N...

The term “acute coronary syndrome” encompasses a range of thrombotic coronary artery diseases, including unstable angina and both ST-segment elevation and non–ST-segment elevation myocardial infarction. Diagnosis requires an electrocardiogram and a careful review for signs and symptoms of cardiac ischemia. In acute coronary syndrome, common electrocardiographic abnormalities include T-wave tenting or inversion, ST-segment elevation or depression (including J-point elevation in multiple leads), and pathologic Q waves. Risk stratification allows appropriate referral of patients to a chest pain center or emergency department, where cardiac enzyme levels can be assessed. Most high-risk patients should be hospitalized. Intermediate-risk patients should undergo a structured evaluation, often in a chest pain unit. Many low-risk patients can be discharged with appropriate follow-up. Troponin T or I generally is the most sensitive determinant of acute coronary syndrome, although the MB isoenzyme of creatine kinase also is used. Early markers of acute ischemia include myoglobin and creatine kinase–MB subforms (or isoforms), when available. In the future, advanced diagnostic modalities, such as myocardial perfusion imaging, may have a role in reducing unnecessary hospitalizations. Acute coronary syndrome encompasses a spectrum of coronary artery diseases, including unstable angina, ST-elevation myocardial infarction (STEMI; often referred to as “Q-wave myocardial infarction”), and no...

This page covers the ECG signs of myocardial ischaemia seen with non-ST-elevation acute coronary syndromes ( NSTEACS). ST-elevation and Q-wave myocardial infarction patterns are covered elsewhere: Myocardial Ischaemia Background Non-ST-elevation acute coronary syndrome ( NSTEACS) encompasses two main entities: • Non-ST-elevation myocardial infarction ( NSTEMI). • Unstable angina pectoris ( UAP). The differentiation between these two conditions is usually retrospective, based on the presence/absence of raised cardiac enzymes at 8-12 hours after the onset of chest pain. Both produce the same spectrum of ECG changes and symptoms and are managed identically in the Emergency Department. Patterns of Myocardial Ischaemia Two main ECG patterns associated with NSTEACS: • • While there are numerous conditions that may simulate myocardial ischaemia (e.g. dynamic ST segment and T wave changes (i.e. different from baseline ECG or changing over time) are strongly suggestive of myocardial ischaemia. Other ECG patterns of ischaemia • • Another, less well-known ECG feature of myocardial ischaemia is Morphology of ST Depression • ST depression can be either upsloping, downsloping, or horizontal (see diagram below). • Horizontal or downsloping ST depression ≥ 0.5 mm at the J-point in ≥ 2 contiguous leads indicates myocardial ischaemia ( according to the • ST depression ≥ 1 mm is more specific and conveys a worse prognosis. • ST depression ≥ 2 mm in ≥ 3 leads is associated with a high probabi...

The standard 12 lead serial 12 lead ECGs, particularly if the first ECG is obtained during a pain-free episode. Alternatively, many Main patterns [ ] The 12 lead ECG is used to classify MI patients into one of three groups: • those with ST segment elevation or new bundle branch block (suspicious for acute injury and a possible candidate for acute reperfusion therapy with • those with ST segment depression or T wave inversion (suspicious for ischemia), and • those with a so-called non-diagnostic or normal ECG. However, a normal ECG does not rule out acute myocardial infarction. ST elevation MI [ ] The 2018 European Society of Cardiology/American College of Cardiology Foundation/American Heart Association/World Health Federation Universal Definition of Myocardial Infarction for the ECG diagnosis of the ST segment elevation type of acute myocardial infarction require new ST elevation at J point of at least 1mm (0.1 mV) in two contiguous leads with the cut-points: ≥1 mm in all leads other than leads V2-V3. For leads V2-V3: ≥2 mm in men ≥40 years, ≥2.5 mm in men <40 years, or ≥1.5 mm in women regardless of age. This assumes usual calibration of 1mV/10mm. There are heavily researched clinical decision tools such as the TIMI Scores which help prognose and diagnose STEMI based on clinical data. For example, TIMI scores are frequently used to take advantage of EKG findings to prognose patients with MI symptoms. [ citation needed] Typical progression [ ] Sometimes the earliest prese...

The standard 12 lead serial 12 lead ECGs, particularly if the first ECG is obtained during a pain-free episode. Alternatively, many Main patterns [ ] The 12 lead ECG is used to classify MI patients into one of three groups: • those with ST segment elevation or new bundle branch block (suspicious for acute injury and a possible candidate for acute reperfusion therapy with • those with ST segment depression or T wave inversion (suspicious for ischemia), and • those with a so-called non-diagnostic or normal ECG. However, a normal ECG does not rule out acute myocardial infarction. ST elevation MI [ ] The 2018 European Society of Cardiology/American College of Cardiology Foundation/American Heart Association/World Health Federation Universal Definition of Myocardial Infarction for the ECG diagnosis of the ST segment elevation type of acute myocardial infarction require new ST elevation at J point of at least 1mm (0.1 mV) in two contiguous leads with the cut-points: ≥1 mm in all leads other than leads V2-V3. For leads V2-V3: ≥2 mm in men ≥40 years, ≥2.5 mm in men <40 years, or ≥1.5 mm in women regardless of age. This assumes usual calibration of 1mV/10mm. There are heavily researched clinical decision tools such as the TIMI Scores which help prognose and diagnose STEMI based on clinical data. For example, TIMI scores are frequently used to take advantage of EKG findings to prognose patients with MI symptoms. [ citation needed] Typical progression [ ] Sometimes the earliest prese...

This page covers the ECG signs of myocardial ischaemia seen with non-ST-elevation acute coronary syndromes ( NSTEACS). ST-elevation and Q-wave myocardial infarction patterns are covered elsewhere: Myocardial Ischaemia Background Non-ST-elevation acute coronary syndrome ( NSTEACS) encompasses two main entities: • Non-ST-elevation myocardial infarction ( NSTEMI). • Unstable angina pectoris ( UAP). The differentiation between these two conditions is usually retrospective, based on the presence/absence of raised cardiac enzymes at 8-12 hours after the onset of chest pain. Both produce the same spectrum of ECG changes and symptoms and are managed identically in the Emergency Department. Patterns of Myocardial Ischaemia Two main ECG patterns associated with NSTEACS: • • While there are numerous conditions that may simulate myocardial ischaemia (e.g. dynamic ST segment and T wave changes (i.e. different from baseline ECG or changing over time) are strongly suggestive of myocardial ischaemia. Other ECG patterns of ischaemia • • Another, less well-known ECG feature of myocardial ischaemia is Morphology of ST Depression • ST depression can be either upsloping, downsloping, or horizontal (see diagram below). • Horizontal or downsloping ST depression ≥ 0.5 mm at the J-point in ≥ 2 contiguous leads indicates myocardial ischaemia ( according to the • ST depression ≥ 1 mm is more specific and conveys a worse prognosis. • ST depression ≥ 2 mm in ≥ 3 leads is associated with a high probabi...

• ST segment elevation with subsequent Q wave formation in precordial leads (V1-6) +/- high lateral leads. These changes are often preceded by hyperacute T waves • Reciprocal ST depression in inferior leads (mainly III and aVF) NB: The magnitude of reciprocal change in inferior leads is determined by the magnitude of ST elevation in I and aVL (as these leads are electrically opposite III and aVF), and hence may be minimal or absent in anterior STEMIs that do not involve high lateral leads. Clinical Relevance of Anterior Myocardial Infarction Anterior STEMI usually results from occlusion of the A • In-hospital mortality (11.9 vs 2.8%) • Total mortality (27 vs 11%) • Heart failure (41 vs 15%) • Significant ventricular ectopic activity (70 vs 59%) • Lower ejection fraction on admission (38 vs 55%) In addition to anterior STEMI, other high-risk presentations of anterior ischaemia include Patterns of Anterior Infarction The nomenclature of anterior infarction can be confusing, with multiple different terms used for the various infarction patterns. The following is a simplified approach to naming the different types of anterior MI. The precordial leads can be classified as follows: • Septal leads = V1-2 • Anterior leads = V3-4 • Lateral leads = V5-6 The different infarct patterns are named according to the leads with maximal ST elevation: • Septal = V1-2 • Anterior = V2-5 • Anteroseptal = V1-4 • Anterolateral = V3-6, I + aVL • Extensive anterior / anterolateral = V1-6, I + aVL N...