What indicates myocardial infarction on ECG?
One of the most significant findings of myocardial infarction is the presence of ST segment elevation. The ST segment is the part of the ECG tracing that starts at the end of the S wave and ends at the beginning of the T wave. The point where the end of the Q wave and the ST segment meet is called the J point.
What is aVR aVL and aVF in ECG?
aVR means augmented Vector Right; the positive electrode is on the right shoulder. aVL means augmented Vector Left; the positive electrode is on the left shoulder. aVF means augmented Vector Foot; the positive electrode is on the foot.
How is an ECG used to diagnose myocardial infarction?
Introduction to ECG Recognition of Myocardial Infarction. In general, the more leads of the 12-lead ECG with MI changes (Q waves and ST elevation), the larger the infarct size and the worse the prognosis. Additional leads on the back, V7-9 (horizontal to V6), may be used to improve the recognition of true posterior MI.
Where are ECG changes seen in anterior precordial leads?
ECG changes are seen in anterior precordial leads V1-3, but are the mirror image of an anteroseptal MI: Increased R wave amplitude and duration (i.e., a “pathologic R wave” is a mirror image of a pathologic Q)
Can a non ST segment elevation myocardial infarction be diagnosed by ECG?
It is not possible to diagnose a non-ST segment elevation myocardial infarction by ECG alone. Patients are treated presumptively and diagnosis is made if the level of serum cardiac markers rise over several hours. Where is the ischemic lesion?
Which is a warning sign of anterior myocardial infarction?
Wellens syndrome: deep precordial T wave inversions or biphasic T waves in V2-3, indicating critical proximal LAD stenosis (a warning sign of imminent anterior infarction) De Winter T waves: upsloping ST depression with symmetrically peaked T waves in the precordial leads; a “STEMI equivalent” indicating acute LAD occlusion.
