Of patients with cardiac injury, only 22 (26.8%) underwent examination of electrocardiogram (ECG) after admission, and 14 of 22 ECGs (63.6%) were performed during the periods of elevation of cardiac biomarkers. All 14 ECGs were abnormal, with findings compatible with myocardial ischemia, such T-wave depression and inversion, ST-segment depression, and Q waves. The ECG changes in 3 patients with representative cardiac injury are shown in eFigure 2 in the

ECG (Panel A) showed low atrial ectopic rhythm, mild ST-segment elevation in leads V1–V2 and aVR, reciprocal ST depression in V4–V6, and QTc 452 ms with diffuse U-waves. The high-sensitivity troponin T curve was 135–107–106 ng/L (normal value <14), NT-proBNP 512 pg/mL (normal value <153), and C-reactive protein 18 mg/L (normal value <6). Transthoracic echocardiogram showed mild left ventricular systolic dysfunction (LVEF 43%) with inferolateral wall hypokynesis; neither ventricle was dilated and there was no pericardial effusion.

A 12-lead electrocardiogram (ECG) showed low voltage in the limb leads, minimal diffuse ST-segment elevation (more prominent in the inferior and lateral leads), and an ST-segment depression with T-wave inversion in lead V1 and aVR