What is proximal LAD occlusion?
Abstract. Proximal occlusion within the left anterior descending (LAD) coronary artery in patients with acute myocardial infarction leads to higher mortality than does nonproximal occlusion. We evaluated an automated program to detect proximal LAD occlusion.
What ECG changes are associated with an occlusion to the left anterior descending artery?
Occlusion in the left circumflex artery ECG changes resemble those seen in posterior infarction due to occlusion in the RCA, namely ST-segment elevations in V7–V9 and reciprocal ST-segment depressions in V1–V3, along with high R-waves and positive T-waves in the same leads (V1–V3).
Which leads on the electrocardiogram most commonly show ST segment elevation in the proximal occlusion of the left anterior descending artery *?
However, acute occlusion of the left anterior descending (LAD) coronary artery that causes anterior wall infarction generally shows ST-Segment elevation in the precordial leads.
What part of the ECG is typically affected when a patient experiences a complete occlusion of the proximal portion of the left anterior descending coronary artery?
The second ECG shows the complete occlusion of the proximal LAD. This was explained with an ischemia of anterior wall, because there were not collaterals from other coronary arteries.
Where is the proximal LAD artery?
In this interim analysis, proximal LAD was defined according to the CASS (Coronary Artery Surgery Study) classification11: end of left main to the first large septal or first diagonal, whichever is more proximal.
Which of the following findings on electrocardiogram are indicative of left main coronary artery occlusion?
Classic findings on ECG that are taught to represent LMCA “occlusion” are: ST depression in leads I, II, aVL and V4-6. ST elevation in aVR ≥ 1mm. ST elevation in aVR ≥ V1.
What is proximal left anterior descending artery?
The prognosis of patients with coronary artery disease is related to the extent of myocardium at risk. Proximal left anterior descending coronary artery (LAD) lesions often supply a high percentage of the left ventricular myocardium, compared to proximal lesions in the circumflex or right coronary arteries.
What is the third electrocardiographic pattern associated with myocardial infarction?
In a myocardial infarction transmural ischemia develops. In the first hours and days after the onset of a myocardial infarction, several changes can be observed on the ECG. First, large peaked T waves (or hyperacute T waves), then ST elevation, then negative T waves and finally pathologic Q waves develop.
What does Lad occlusion mean on ECG?
This ECG constellation of findings is associated with significant proximal left anterior descending artery (LAD) occlusion (Figure 4) and ultimately anterior wall STEMI. In fact, recent publications have suggested that this ECG pattern should be treated as a STEMI equivalent presentation based on angiographic evidence. 3-6
What is the significance of proximal Lad occlusion?
This pattern is seen in proximal LAD occlusion and indicates a large territory infarction with a poor LV ejection fraction and high likelihood of cardiogenic shock and death The site of LAD occlusion (proximal versus distal) predicts both infarct size and prognosis.
What does a septal Lad occlusion look like on ECG?
This patient’s ECG shows several signs of a very proximal LAD occlusion (Ostial LAD occlusion (septal STEMI)): There is a septal STEMI with ST elevation maximal in V1-2 (extending out to V3). There is a new RBBB with marked ST elevation (> 2.5 mm) in V1 plus STE in aVR — these features suggest occlusion proximal to S1.
What is the pathophysiology of proximal Lad occlusion with STEMI?
Proximal LAD occlusion leading to STEMI usually presents in two contiguous leads and frequently involves V3 or V4 in addition to V2, but the pattern may differ depending on the location of the lesion.