Subendocardial ischemia and acute phase of infarction

ECG 2A: At hospital entry, the electrocardiogram, recorded in the absence of pain, is within the normal limits (sinus rhythm, absence of conduction disorder, isoelectric ST-segment and T-waves without abnormality);

During hospitalization, the patient developed typical chest pain with recording of this electrocardiogram after 1 hour (the patient took a long time to report the pain to the nurse);

ECG 2B: Compared to the previous tracing, modification of the electrocardiogram with signs of subendocardial ischemia (significant increase in T-wave amplitude in V3-V5, peaked and symmetrical T-waves); ST-segment remaining more or less isoelectric;

ECG 2C: No particular treatment was proposed; ECG recorded 2 hours after onset of pain; emergence of elevation in the leads previously exhibiting subendocardial ischemia with persistence of a tall T-wave; reciprocity (depression) in the inferior leads;

ECG 2D: The coronary angiography revealed an occlusion of the LAD with angioplasty and stent placement; electrocardiogram performed on D3 with inversion of T-waves in the same territory;Comments: in this patient, the first electrical sign of coronary occlusion is the presence of subendocardial ischemia with a marked increase in the amplitude of the T-waves which become symmetrical and peaked in the absence of changes in the pattern of the QRS-complex or the ST-segment which remains isoelectric. This pattern of isolated “giant” T-waves without elevation in the hyperacute phase of an occlusion is transitory and never exceeds the fourth hour; indeed, if the ischemia persists and becomes transmural and no therapy is undertaken, these changes announce the appearance of a Pardee wave with elevation in the same territory. The electrocardiographic recording of this type of tracing is therefore relatively rare.

Take-home message: The highlighting of tall, symmetrical and peaked T-waves in the aftermath of a very recent chest pain should evoke the presence of a coronary occlusion and therefore warrant performing an emergency reperfusion.