ECG, Holter monitoring, and laboratory data
- Physical examination including checking for heart regularity and rate was done on daily basis. - Routine ECG was performed on admission and whenever new cardiac symptoms appeared or an arrhythmia was suspected on physical examination or telemetry. - Laboratory examination was not done routinely but on clinical basis for patients with cardiac symptoms, general deterioration and before treatment with Hydroxychloroquine and/or Azithromycin. . - 24-hour Holter monitoring was performed in a minority of patients, primarily those with evidence of cardiac injury, abnormal ECG on admission, or those with significant illness.