Q waves are present in both the anterior and lateral leads, most prominently in V2-4. Technical errors in acquiring echo imaging plane or it’s interpretation is the commonest . Be the best at electrocardiography! Tall, broad R waves (> 30ms) in V2-3. Cases by Type. However, the subtle myocardial infarction (MI) may be easily overlooked, especially in patients with underlying ECG abnormalities. 3 Example 2a : Poterior STEMI (anterior leads) In this ECG, posterior MI is suggested by the presence of: ST depression in V2-3. ST-segment elevation myocardial infarction; Acute Coronary Syndrome (Main) Chest pain; ECG (Main) References ST ELEVATION, CONSIDER ANTERIOR INJURY . 58 59 Although the specificity of various combinations of ECG elements for Takotsubo may be > 95%, the positive predictive value may be as low as 67% due to the low prevalence of Takotsubo. Upright terminal portions of the T waves in V2-3 . Cath lab was cancelled. Overview of the separate ECG leads. Right Lead Positioning. The EKG suggests an inferior wall infarction, probably old. During right ventricular pacing the ECG also shows left bundle brach block and the above rules also apply for the diagnosis of myocardial infarction during pacing, however they are less specific. The anteroseptal leads are directed from the anterior precordium towards the internal surface of the posterior myocardium. Anterior STEMI. In V2-3 : = 0.2 mV in men > 40 years = 0.25 mV in men ; 40 years = 0.15 mV in women in V2-3 ; In other leads > 0.1 mV for both sexes ; Hyperacute T waves. Anterior STEMI is produced by a thrombus in the left anterior descending artery (LAD), which supplies the anterior surface of the left ventricle. The ST depression is often deep (>2mm) and flat (horizontal). It is therefore an acute MI, but in this case it is a type 2 MI due to tachycardia supply-demand mismatch. Lead aVL is an underutilized lead for localizing the area of acute infarction. Analysis--There is much "anterior" (right precordial) ST elevation.--There is also high voltage, which suggests … ** A inferior MI due to a dominant LCX and a large OMs have comparable outcome as that of extensive anterior MI. However, isolated posterior MI, while less common (3-11% of infarcts 2), is important to recognize as it is also an indication for reperfusion and can be missed by the ECG reader. Anterior myocardial infarction is a term denoting ischemia and necrosis of the anterior myocardial wall due to occlusion of the left anterior descending artery. Standard EKG Changes (similar to anterior MI EKG when rotated 180 degrees) ST Elevation in leads I and aVF, and lead III more than II; ST depression in leads I, aVL (reciprocal to posterior changes) Right sided EKG. Most physicians are very comfortable with the classic electrocardiographic (ECG) findings of ST changes, T-wave inversions, and Q waves in myocardial ischemia or infarction. Although earlier work had suggested that ECG criteria might distinguish this STE from anterior STEMI, 57 recent literature does not support this result. Many times , obliquely obtained long axis view wrongly and strongly suggests a septal MI instead of inferior posterior MI. Therefore, ST segments in leads overlying the posterior region of the heart (V1 and V2) are initially horizontally depressed. Here is the troponin profile (contemporary troponin I, URL = 0.030 ng/mL): It rose and fell, with one value above the 99th percentile URL. Hyperacute T waves: are tall, often asymmetrical, broad-based anterior T waves often associated with reciprocal ST depression. Amal Mattu’s ECG Case of the Week – June 22, 2020. LM = 'Left Main' = mainstem; LAD = 'Left Anterior Descending' artery; RCX = Ramus Circumflexus; RCA = 'Right Coronary Artery'. Most striking is probably the clearly-seen anterior-septal wall M.I. TYPE 2 BRUGADA PATTERN [SADDLEBACK ST ELEVATION] ***ACUTE MI*** Is this Acute MI? Up to 40% of patients with an inferior STEMI will have a concomitant right ventricular infarction. The ECG will reveal ST elevation in both inferior and lateral leads. In the GUSTO-1 trial the ECG criterion with a high specificity and statistical significance for the diagnosis of an acute MI was: ST segment elevation ≥5 mm in leads with a negative QRS complex. Cases by Month Cases by Month. MI diagnosis in left bundle branch block or paced rhytm; MI Diagnosis in RBBB; The location of the infarct. Anterior MI. ECG findings: The ECG in posterior STEMI is first characterized by ST-depression in the anterior leads. Group Management; Group Progress Report; Group Cases; FAQ; Our Team; Join Today! It is obtained from a man with chest pain. Inferior MI accounts for 40-50% of all myocardial infarctions. How common is that ? There is also slight ST elevation in the inferior leads and T wave inversion. Wellens syndrome is a pattern of deeply inverted or biphasic T waves in V2-3, which is highly specific for a critical stenosis of the left anterior descending artery (LAD).. Generally have a more favourable prognosis than anterior myocardial infarction (in-hospital mortality only 2-9%), however certain factors indicate a worse outcome. The 12 lead ECG is used to classify MI patients into one of three groups: ... V6 correspond to the lateral wall; V3-V4 correspond to the anterior wall ; V1-V2 correspond to the septal wall; II, III, aVF correspond to the inferior wall.) “Inferior MI” by ECG . The QRS shows Q waves in the inferior leads which are wide (>30ms) and about 25% of the QRS height in aVF. Furthermore, ECG localization was categorized as follows: inferior changes when the ECG pattern met the criteria mentioned above in ≥2 of 3 leads (II, III, and avF), anteroseptal when it applies in ≥2 of 3 leads (V1, V2, and V3), lateral in ≥2 of 4 leads (I, avL, V5, and V6), and anterior in ≥4 of 6 leads (V1, V2, V3, V4, V5, and V6). But “because of this absence of pathologic Q waves, strictly posterior infarction is one of the most commonly overlooked electrocardiographic abnormalities.” (1). An overview of the coronary arteries. Join Today! When examining the ECG from a patient with a suspected posterior MI, it is important to remember that because the endocardial surface of the posterior wall faces the precordial leads, changes resulting from the infarction will be reversed on the ECG. Shown below is an EKG demonstrating sinus rhythm. A 54-year-old female asked: ecg reads "cannot rule out previous anterior mi" and " minimal requirements met for current anterior infarct, abnormal comp to previous ecg"?explain? The lead with ST segment elevation 'highlights' the infarct. 12-Lead ECG findings QRS > 0.12 in limb leads; Leads Large and wide R waves — leads I, aVL, V5, and V6; Small R wave followed by deep S wave —leads II, III, aVF, V1–V3; External Links. An anterior MI will manifest ST-segment depression in the inferior leads when there is a more proximal LAD occlusion (the first diagonal branch is occluded) [4, 14]. ST elevation in V1 + ST depression in V2 (= highly specific for RV MI). KEY Point — ST-T waves that look the same as those in true Wellens’ Syndrome may be seen as a result of reperfusion after an MI. There is ST segment elevation in Leads V 1, V 2, and … 28 years experience Cardiology. This is an interesting teaching ECG on many levels. If you see ST-depression leads II, III, or aVF, you should carefully scrutinize the ECG for subtle anterior (V1-4) or high lateral (I, aVL) ST-segment elevation or hyperacute T-waves. Patient 6: 75yo with two days chest pain radiating to the shoulders, now constant for 90 minutes. A 63 year old woman with 10 hours of chest pain and sweating. Dominant R wave (R/S ratio > 1) in V2. They agreed that the ECG findings were due only to old MI and tachycardia. “Anterior MI” by echocardiography . Possible causes for this wrong call . De Winter ST-T complex. ***In patients with prior CAD and collateral dependent multivessel disease the inferior anterior sub classification does not make much sense as entire coronary circulation can be mutually interdependent. If anterior Q waves (or QS complexes) are already present — then the infarct has already occurred, which means it is too late for such an ECG to represent “Wellens’ Syndrome”. This criterion is problematic, however, as acute myocardial infarction is not the most common cause of ST segment elevation in chest pain patients. An ECG was recorded: This was the automated interpretation: SINUS RHYTHM. LEFT VENTRICULAR HYPERTROPHY AND ST-T CHANGE . 12-lead ECG library, anterior myocardial infarction. This pattern indicates an extensive infarction involving the anterior and lateral walls of the left ventricle Old ECG then serial ECGs: Patient 7: 40yo with 12 hours of chest pain and shortness of breath, began on exertion and refractory to nitro. Right ventricular infarction is confirmed by the presence of ST elevation in the right-sided leads (V3R-V6R). Acute anterior myocardial infarction . . A sudden onset of chest pain that often radiates to the arm and neck accompanied by dyspnea, nausea, vomiting, weakness, and diaphoresis are some of the most common symptoms. . Learning Points: 1. A study in 1964 found that posterior MIs produce tall anterior R waves, and differentiated it from other causes (pediatric ECG, WPW, RBBB, RVH, and normal variant). Old then new ECG. Right-sided leads There are several approaches to recording a right-sided ECG: ST-segment elevation at the J point in two contiguous ECG leads. SEE FULL CASE. Master ECG interpretation from our nationally-known educators. Amal Mattu ECG Case: April 29 2012; See Also. There is reciprocal ST depression in the inferior leads (III and aVF). ST elevation is present in the anterior (V2-4) and lateral leads (I, aVL, V5-6). Get … Patient 5: 85yo with one hour of chest pain radiating to the arm. Acute M.I. ekg anterior mi. No other history or follow up is available. ECG Weekly; CME; ECGStat; Pricing; Weekly Cases; Group Purchase. The prognosis of patients with anterior wall MI (AWMI) is significantly worse than patients with inferior wall MI. Anterior MI is associated with more myocardial damage than inferior infarction; this damage affects LV function, a major determinant in prognostic outcome after acute MI. Left ventricular aneurysm: An LV aneurysm can be diagnosed on ECG when there is persistent ST segment elevation occurring 6 weeks after a known transmural MI (usually anterior). Dr. Anita Prakash answered. Isoelectric ST segment in V1 with marked ST depression in V2. ST segment elevations are seen in leads V 2-V 4, with reciprocal changes in inferior leads (II, III, and aVF). Lateral STEMI vs Occlusion MI Clinical Significance.