Which leads are affected in anterior MI?
When a patient has an anterior-wall MI, you’ll see the indicative changes in leads V1 through V4 and the reciprocal changes in lateral leads I and aVL and inferior leads II, III, and aVF.
What leads show a posterior MI?
The ECG findings of an acute posterior wall MI include the following: ST segment depression (not elevation) in the septal and anterior precordial leads (V1-V4). This occurs because these ECG leads will see the MI backwards; the leads are placed anteriorly, but the myocardial injury is posterior.
What leads show a lateral infarction?
A lateral myocardial infarction (MI) is a heart attack or cessation of blood flow to the heart muscle that involves the inferior side of the heart. Inferior MI results from the total occlusion of the left circumflex artery. Lateral MI is characterized by ST elevation on the electrocardiogram (EKG) in leads I and aVL.
What artery is affected in lateral MI?
More commonly the left anterior descending (LAD) coronary artery is involved in the ensuing anterolateral MI.
Why does ST elevation indicate MI?
An acute ST-elevation myocardial infarction occurs due to occlusion of one or more coronary arteries, causing transmural myocardial ischemia which in turn results in myocardial injury or necrosis.
Why does anterior MI cause tachycardia?
The elevated heart rate increases myocardial oxygen demand, and a decreased length of diastole compromises coronary flow, worsening myocardial ischemia. Causes of persistent sinus tachycardia include the following: Pain.
How can you tell the difference between anterior and posterior STEMI?
Look for deep (>2mm) and horizontal ST-segment depression in the anterior leads and large anterior R-waves (bigger than the S-wave in V2). Posterior STEMI often occurs along with an inferior or lateral STEMI, but can also occur in isolation.
What are the lateral leads?
The septum is represented on the ECG by leads V1 and V2, whereas the lateral wall is represented by leads V5, V6, lead I and lead aVL.
Which leads are considered high lateral leads?
High Lateral STEMI
- ST elevation primarily localised to leads I, aVL +/- V2.
- Reciprocal ST depression and/or T wave inversion in inferior leads, most pronounced in lead III.
Which coronary artery is affected in anterior MI?
Occlusion of the left anterior descending coronary artery (LAD) may cause infarction of the anterior wall of the left ventricle, manifested as precordial ST-segment elevations.