Fig. 4

Three ECGs presented with both the standard presentation of limb leads (a) and the Cabrera sequence (b). Precordial leads are presented in columns c. 1. ECG from a patient with RCA occlusion. The myocardium at risk was large (37%) according to cardiac magnetic resonance imaging. There is ST elevation in II, III, aVF, V3 − V6 and ST depression in aVL, I and V1-V2. In the standard format, ECG shows significant ST elevation in two contiguous limb lead pairs; II/aVF and III/aVF. In the Cabrera format, ST depression in aVR is replaced by ST elevation in −aVR and ST elevation is thus evident in one additional lead pair, −aVR/II. The ST depression is larger in aVL than in I and the ST elevation is larger in III than in II. The inferior STEMI is easily recognized with the standard format, but in the Cabrera sequence, with −aVR presented adjacent to lead II, the extent of the infarction is more easily appreciated. 2. ECG from a patient with left main stenosis. Precordial leads show ST depression in V2 − V6 (c). In the standard format (a), ECG shows ST depression in I, II, III, aVF and ST elevation in aVR. In the Cabrera display (b), ST elevation in aVR is replaced by ST depression in −aVR with a smooth transition from the ST depression in its neighboring leads, in a way “de-mystifying” the ST elevation in aVR as a unique finding of severe coronary heart disease. 3. ECG from a patient with proximal LAD occlusion. ST elevation in anterior leads in combination with ST elevation in aVR in the standard presentation (a) is a sign of proximal LAD occlusion [16, 37]. In the Cabrera sequence (b), ST elevation in aVR is displayed as ST depression in −aVR, which makes it easy to appreciate the ST -segment progression. In the frontal plane, the ST vector is directed towards the left and ST elevation in aVL is present − a sign of LAD occlusion proximal to the first diagonal branch