Electrocardiogram evolution of acute anterior ST‐segment elevation myocardial infarction following pericarditis

FIGURE 1. (a): An emergency ECG recording shows ST‐segment elevation and PR‐segment depression in the anterior (V2–6) and inferior (II III aVF) leads with concomitant PR‐segment elevation in lead aVR. Also, low voltages (<5 mV) in six limb leads were observed. (b): Magnified recording from lead I with isoelectric ST segment and V2 with maximal ST‐segment elevation showing differences in the QRS complex duration (Δ). (c): Pericarditis with pericardial effusion as revealed by computed tomography (arrow). (d): An ECG recording 1 hour after thrombolytic therapy demonstrates that the amplitudes of the ST‐segments in V2‐V6 have been reduced to half of their original amplitude, though the amplitude of ST‐segment elevation in inferior leads increased and PR‐segment depression in inferior leads as well as PR‐segment elevation in lead aVR did not exhibit significant changes. Moreover, Spodick's sign, a downsloping of the ECG baseline (the TP segment), indicating pericarditis, became obvious (arrow)

FIGURE 2. Variation in ECG after thrombolytic therapy mainly shows a dynamic evolution of ST‐T waves in leads V1‐V6 rather than in six limb leads

FIGURE 3. (a): Coronary angiogram showed that the culprit lesion was located on the proximal‐to‐mid left anterior descending artery (LAD) and the stenosis was close to both the first diagonal branch (D1) and the first septal perforator (S1). (b): Coronary angiogram after LAD stenting. (c): An ECG recording after stenting shows ST‐segment elevation. Also, PR‐ segment depression in inferior leads still exists, accompanied by PR‐ segment elevation in lead aVR. (d): A mild increase in pericardial effusion was revealed by echocardiogram (arrow)