Unfortunately, LAD occlusion does not always present with reciprocal changes, so we need to have other strategies to help rule-in the diagnosis.
hyper acute T does not only means T above 1.5 big squares -also when T wave considered large if compared with QRS it is an abnormal one
LAD occlusion often (but not always) obliterates the R-waves in the anterior leads. When R-wave progression is obliterated, you know it can’t be early repolarization!
when the LAD reperfuses, we usually get Wellens' waves (reperfusion T-waves). So even though the ECG never manifested outright STEMI, the small amount of infarct that resulted from this subtotal occlusion resulted in the same T-wave evolution that we would have seen with outright STEMI.
Wellens' syndrome (Wellens' sign, Wellens' warning, or Wellens' waves) is an electrocardiographic manifestation of critical proximal left anterior descending (LAD) coronary artery stenosis in patients with unstable angina. It is characterized by symmetrical, often deep (>2 mm), T wave inversions in the anterior precordial leads. A less common variant is biphasic T wave inversions in the same leads.[1]
The presence of Wellens' syndrome carries significant diagnostic and prognostic value. All patients in the De Zwann's study with characteristic findings had more than 50% stenosis of the left anterior descending artery (mean = 85% stenosis) with complete or near-complete occlusion in 59%. In the original Wellens' study group, 75% of those with the typical syndrome manifestations had an anterior myocardial infarction. Sensitivity and specificity for significant (more or equal to 70%) stenosis of the LAD artery was found to be 69% and 89%, respectively, with a positive predictive value of 86%.
---------------------------------------هنا MI without the classic criteria
here there is largeT+poor R PROPAGATION
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